Biology 1A - Summary One

Biology revision

HideShow resource information
  • Created by: Chelsea
  • Created on: 03-06-10 20:14

A Sense Organ

What is a Sense Organ?

1 of 212

A Sense Organ

What is a Sense Organ?

2 of 212

A Receptor

What is a Receptor?

3 of 212

A Sense Organ

A sense organ is the organ which detects the stimulus these are:

- EYES

- EARS

- NOSE

- TONGUE

- SKIN

4 of 212

A Stimulus

What is a Stimulus?

5 of 212

A Receptor

Receptors are groups of cells which are sensitive to a stimulus - they change stimulus energy into electrical impulses.

- EYES: Light receptors

- EARS: Sound and 'balance' receptors

- NOSE: Smell receptors (chemical stimuli)

- TONGUE: Taste receptors

- SKIN: Receptors sensitive to touch, pressure and temperature change

6 of 212

A Stimulus

A stimulus is a change in your environment, which you may need to react to (e.g. a recently pounced tiger).

7 of 212

A Sense Organ

A sense organ is the organ which detects the stimulus these are:

- EYES

- EARS

- NOSE

- TONGUE

- SKIN

8 of 212

A Sensory Neurone

What is a Sensory Neurone?

9 of 212

A Sensory Neurone

Sensory neurones are the nerve cells that carry signals as electrical impulses from the receptors in the sense organs to the CNS (central nervous system).

10 of 212

A Stimulus

A stimulus is a change in your environment, which you may need to react to (e.g. a recently pounced tiger).

11 of 212

A Motor Neurone

What is a Motor Neurone?

12 of 212

A Sensory Neurone

What is a Sensory Neurone?

13 of 212

Motor Neurones are the nerve cells that carry signals from the CNS to the effector (muscle or gland).

14 of 212

A Sensory Neurone

Sensory neurones are the nerve cells that carry signals as electrical impulses from the receptors in the sense organs to the CNS (central nervous system).

15 of 212

The Central Nervous System (CNS)

What is the Central Nervous System?

16 of 212

A Motor Neurone

What is a Motor Neurone?

17 of 212

The Central Nervous System (CNS)

The Central Nervous System (CNS), is where all the information from the sense organs is sent, and where reflexes and actions are coordinated. The CNS consists of the brain and spinal cord only.

18 of 212

Motor Neurones are the nerve cells that carry signals from the CNS to the effector (muscle or gland).

19 of 212

A Synapse

What is a Synapse?

20 of 212

The Central Nervous System (CNS)

What is the Central Nervous System?

21 of 212

A Synapse

A Synapse is the 'junction' between two neurones. The nerve signal is transferred by chemicals which diffuse (move) across the gap - which then set off a new electrical signal in the next neurone.

22 of 212

The Central Nervous System (CNS)

The Central Nervous System (CNS), is where all the information from the sense organs is sent, and where reflexes and actions are coordinated. The CNS consists of the brain and spinal cord only.

23 of 212

A Reflex Arc

What is a Reflex Arc?

24 of 212

A Reflex Arc

The reflex arc is the passage of information in a reflex action (from receptor to effector). We have reflex actions because sometimes waiting for your brain to make a decision is too slow, therefore we have automatic responses to certain stimuli - and they reduce the risks of us being injured.

Here is a diagram to display a reflex arc:

Stimuli>Receptor>Sensory Neurone>Relay Neurone>Motor Neurone>Effector>Response

25 of 212

A Synapse

What is a Synapse?

26 of 212

A Hormone

What is a hormone?

27 of 212

A Synapse

A Synapse is the 'junction' between two neurones. The nerve signal is transferred by chemicals which diffuse (move) across the gap - which then set off a new electrical signal in the next neurone.

28 of 212

A Reflex Arc

What is a Reflex Arc?

29 of 212

A Hormone

Hormones are chemical messengers which travel in the blood to activate target cells.

30 of 212

A Reflex Arc

The reflex arc is the passage of information in a reflex action (from receptor to effector). We have reflex actions because sometimes waiting for your brain to make a decision is too slow, therefore we have automatic responses to certain stimuli - and they reduce the risks of us being injured.

Here is a diagram to display a reflex arc:

Stimuli>Receptor>Sensory Neurone>Relay Neurone>Motor Neurone>Effector>Response

31 of 212

The Pituitary Gland

What is the Pituitary Gland?

32 of 212

A Hormone

What is a hormone?

33 of 212

The Pituitary Gland

The pituitary gland is located just below the brain, and produces many important hormones including LH (luteinising hormone), FSH (follicle-stimulating hormone) and ADH (controls water content).

34 of 212

A Hormone

Hormones are chemical messengers which travel in the blood to activate target cells.

35 of 212

The Pancreas

What is the Pancreas?

36 of 212

The Pituitary Gland

What is the Pituitary Gland?

37 of 212

The Pancreas

The Pancreas is located just infront of the kidneys, and produces insulin for the control of the blood sugar levels in the body.

38 of 212

The Pituitary Gland

The pituitary gland is located just below the brain, and produces many important hormones including LH (luteinising hormone), FSH (follicle-stimulating hormone) and ADH (controls water content).

39 of 212

The Ovaries

What are the Ovaries?

40 of 212

A Receptor

What is a Receptor?

41 of 212

The Ovaries

Ovaries are within females only, and they produce Oestrogen which controls the Menstrual Cycle. Ovaries also promote all female secondary characteristics such as extra body hair, and widening of the hips.

42 of 212

The Pancreas

The Pancreas is located just infront of the kidneys, and produces insulin for the control of the blood sugar levels in the body.

43 of 212

The Testes

What are the Testes?

44 of 212

The Ovaries

What are the Ovaries?

45 of 212

The Testes

Testes appear in men only, and they produce testosterone which promotes all male secondary sexual characteristics at puberty e.g. extra body hair.

46 of 212

The Ovaries

Ovaries are within females only, and they produce Oestrogen which controls the Menstrual Cycle. Ovaries also promote all female secondary characteristics such as extra body hair, and widening of the hips.

47 of 212

FSH (Follice-stimulating hormone)

What is FSH?

48 of 212

The Testes

What are the Testes?

49 of 212

FSH (Follice-stimulating hormone)

FSH (Follice-stimulating hormone), is produced by the pituitary gland, and causes an egg to mature in one of the ovaries, as well as stimulating the ovaries to produce Oestrogen.

50 of 212

The Testes

Testes appear in men only, and they produce testosterone which promotes all male secondary sexual characteristics at puberty e.g. extra body hair.

51 of 212

FSH (Follice-stimulating hormone) 2

How can FSH increase the chances of pregnancy?

52 of 212

FSH (Follice-stimulating hormone)

What is FSH?

53 of 212

FSH (Follice-stimulating hormone) 2

Low levels of FSH mean that there is not enough of the hormone to mature the eggs in the ovaries. Consequently, no eggs are released at the middle of the Menstrual Cycle, and this means that the woman can not get pregnant. Therefore, this hormone can be taken by women to stimulate the production of eggs in the ovaries.

Increased levels of FSH also mean that ovaries are stimulated to produce LH (luteinising hormone), which means your ovaries are stimulated to release eggs.

ADVANATGES - Help women get pregnant

DISADVANTAGES - This process does not always work. Also, sometimes, too many eggs could be stimulated - increasing the chances of multiple births.

54 of 212

FSH (Follice-stimulating hormone)

FSH (Follice-stimulating hormone), is produced by the pituitary gland, and causes an egg to mature in one of the ovaries, as well as stimulating the ovaries to produce Oestrogen.

55 of 212

Oestrogen

What is Oestrogen?

56 of 212

FSH (Follice-stimulating hormone) 2

How can FSH increase the chances of pregnancy?

57 of 212

Oestrogen

Oestrogen is produced in the ovaries, and causes the pituitary gland to produced LH (luteinising hormone), as well as inhibiting any further release of FSH (follicle-stimulating hormone).

58 of 212

FSH (Follice-stimulating hormone) 2

Low levels of FSH mean that there is not enough of the hormone to mature the eggs in the ovaries. Consequently, no eggs are released at the middle of the Menstrual Cycle, and this means that the woman can not get pregnant. Therefore, this hormone can be taken by women to stimulate the production of eggs in the ovaries.

Increased levels of FSH also mean that ovaries are stimulated to produce LH (luteinising hormone), which means your ovaries are stimulated to release eggs.

ADVANATGES - Help women get pregnant

DISADVANTAGES - This process does not always work. Also, sometimes, too many eggs could be stimulated - increasing the chances of multiple births.

59 of 212

LH (Luteinising hormone)

What is LH?

60 of 212

Oestrogen

What is Oestrogen?

61 of 212

LH (Luteinising hormone)

LH, is the hormone produced in the pituitary gland, and it stimulates the release of an egg at around the middle of the Menstrual Cycle.

62 of 212

Oestrogen

Oestrogen is produced in the ovaries, and causes the pituitary gland to produced LH (luteinising hormone), as well as inhibiting any further release of FSH (follicle-stimulating hormone).

63 of 212

The Pill

What is the Pill?

64 of 212

LH (Luteinising hormone)

What is LH?

65 of 212

The Pill

The Pill is an oral contraceptive, which contains Oestrogen. It works by ihibiting the release of FSH, and if the levels of Oestrogen are kept permanatly high, after a while, egg development and production stops and stays stopped.

ADVANTAGES: Over 99% effective, and it reduces the risk of getting some types of cancer.

DISADVANTAGES: Side effects include headaches, nausea and irregular bleeding, and The Pill doesn't protect again sexually transmitted diseases (STDs).

66 of 212

LH (Luteinising hormone)

LH, is the hormone produced in the pituitary gland, and it stimulates the release of an egg at around the middle of the Menstrual Cycle.

67 of 212

IVF (in vitro fertilisation)

What is IVF?

68 of 212

A Receptor

Receptors are groups of cells which are sensitive to a stimulus - they change stimulus energy into electrical impulses.

- EYES: Light receptors

- EARS: Sound and 'balance' receptors

- NOSE: Smell receptors (chemical stimuli)

- TONGUE: Taste receptors

- SKIN: Receptors sensitive to touch, pressure and temperature change

69 of 212

IVF

Also known as 'in vitro fertilisation', IVF is a method used to help women get pregnant. It involves collecting eggs from the woman's ovaries, and fertilising them in a lab with the man's sperm. These are then grown into embryos, and implanted into the uterus.

- Hormones are given before egg collection to stimulate egg production.

- Oestrgen and Progesterone are also given before implantation to increase the chances of the process succeeding.

70 of 212

The Pill

The Pill is an oral contraceptive, which contains Oestrogen. It works by ihibiting the release of FSH, and if the levels of Oestrogen are kept permanatly high, after a while, egg development and production stops and stays stopped.

ADVANTAGES: Over 99% effective, and it reduces the risk of getting some types of cancer.

DISADVANTAGES: Side effects include headaches, nausea and irregular bleeding, and The Pill doesn't protect again sexually transmitted diseases (STDs).

71 of 212

Homeostasis

What is Homeostasis?

72 of 212

IVF (in vitro fertilisation)

What is IVF?

73 of 212

Homeostasis

Homeostasis is the process in which all the functions of the body try to maintain a 'constant internal environment'. The bodily levels which need to be controlled are:

- Ion Content

- Water Content

- Sugar Content

- Temperature

74 of 212

IVF

Also known as 'in vitro fertilisation', IVF is a method used to help women get pregnant. It involves collecting eggs from the woman's ovaries, and fertilising them in a lab with the man's sperm. These are then grown into embryos, and implanted into the uterus.

- Hormones are given before egg collection to stimulate egg production.

- Oestrgen and Progesterone are also given before implantation to increase the chances of the process succeeding.

75 of 212

Ion Content

Why is it important to regulate the ion content?

76 of 212

Homeostasis

What is Homeostasis?

77 of 212

Ion Content

Ion content is regulated by the kidneys. Ions (e.g. sodium) is taken into the body through food. If the food contains too much of any kind of ion, then the excess ions need to be removed. Ions are lost in sweat, as well as removed by the kidneys in urin.

78 of 212

Homeostasis

Homeostasis is the process in which all the functions of the body try to maintain a 'constant internal environment'. The bodily levels which need to be controlled are:

- Ion Content

- Water Content

- Sugar Content

- Temperature

79 of 212

Water Content

Why is it important to regulate the water content in the body?

80 of 212

Ion Content

Why is it important to regulate the ion content?

81 of 212

Water Content

Water is taken into the body with food and drink, and is lost from the body in these ways:

- Through the skin as sweat

- Via the lungs in breath

- Via the kidneys as urine

82 of 212

Ion Content

Ion content is regulated by the kidneys. Ions (e.g. sodium) is taken into the body through food. If the food contains too much of any kind of ion, then the excess ions need to be removed. Ions are lost in sweat, as well as removed by the kidneys in urin.

83 of 212

Body Temperature

Why is it important to regulate the body temperature?

84 of 212

The Pill

What is the Pill?

85 of 212

Body Temperature

All enzymes work best at 37 degrees, and therefore your body aims to maintain this temperature. A part of your brain acts as your own personal thermostat, and is sensitive to the blood temperature.

86 of 212

Water Content

Water is taken into the body with food and drink, and is lost from the body in these ways:

- Through the skin as sweat

- Via the lungs in breath

- Via the kidneys as urine

87 of 212

Blood Sugar

Why is it important to regulate the blood sugar levels?

88 of 212

Body Temperature

Why is it important to regulate the body temperature?

89 of 212

Blood Sugar

Sugar is taken into the body through carbohydrate foods. Metabolism of cells removes glucose from the blood, and so does a balanced daily amount of exercise. However, to maintain the right level, we have the hormone insulin - which removes sugar from our blood. Diabetes (Type 1) is an illness at which your body doesn't produce enough insulin to maintain the correct blood sugar level.

90 of 212

Body Temperature

All enzymes work best at 37 degrees, and therefore your body aims to maintain this temperature. A part of your brain acts as your own personal thermostat, and is sensitive to the blood temperature.

91 of 212

A Balanced Diet

What are the five groups, and their roles?

92 of 212

Blood Sugar

Why is it important to regulate the blood sugar levels?

93 of 212

A Balanced Diet

- Carbohydrates and fats: Keep you warm and provide energy

- Protein: For growth, cell repair and cell replacement

- Fibre: Keep everything moving smoothly in your digestive system

- Vitamins and minerals: Maintain the healthiness of the blood, skin and bones

94 of 212

Blood Sugar

Sugar is taken into the body through carbohydrate foods. Metabolism of cells removes glucose from the blood, and so does a balanced daily amount of exercise. However, to maintain the right level, we have the hormone insulin - which removes sugar from our blood. Diabetes (Type 1) is an illness at which your body doesn't produce enough insulin to maintain the correct blood sugar level.

95 of 212

Metabolism

What is the Metabolism?

96 of 212

A Balanced Diet

What are the five groups, and their roles?

97 of 212

Metabolism

The Metabolism is the chemical reactions which happen within the body to keep you alive. The Metabolic Rate is the speed at which these reactions occur. People with higher proportions of muscle to fat, will have a higher Metabolic Rate.

Regular exercise can boost your resting Metabolic Rate.

98 of 212

A Balanced Diet

- Carbohydrates and fats: Keep you warm and provide energy

- Protein: For growth, cell repair and cell replacement

- Fibre: Keep everything moving smoothly in your digestive system

- Vitamins and minerals: Maintain the healthiness of the blood, skin and bones

99 of 212

Obesity

What is Obesity and what are its effects?

100 of 212

Metabolism

What is the Metabolism?

101 of 212

Obesity

Obesity is the condition at which people become severely overweight, and this can happen because of bad diet, overeating, lack of exercise, or even hormonal problems.

Health problems caused because of obesity include:

- Arthritis (inflamation of the joints)

- Diabetes (inability to control blood sugar levels)

- High blood pressure

- Heart Disease

- Some types of cancer

102 of 212

Metabolism

The Metabolism is the chemical reactions which happen within the body to keep you alive. The Metabolic Rate is the speed at which these reactions occur. People with higher proportions of muscle to fat, will have a higher Metabolic Rate.

Regular exercise can boost your resting Metabolic Rate.

103 of 212

Malnutrition/Starvation

What is Malnutrition/Starvation, and what are the effects of each of them?

104 of 212

Obesity

What is Obesity and what are its effects?

105 of 212

A Stimulus

What is a Stimulus?

106 of 212

Obesity

Obesity is the condition at which people become severely overweight, and this can happen because of bad diet, overeating, lack of exercise, or even hormonal problems.

Health problems caused because of obesity include:

- Arthritis (inflamation of the joints)

- Diabetes (inability to control blood sugar levels)

- High blood pressure

- Heart Disease

- Some types of cancer

107 of 212

Cholesterol 1

What is Cholesterol?

108 of 212

Malnutrition/Starvation

What is Malnutrition/Starvation, and what are the effects of each of them?

109 of 212

A Sense Organ

What is a Sense Organ?

110 of 212

Malnutrition/Starvation

Malnutrition, is the condition of a person when they are given a lack of one of more types of foods.

Starvation is the condition of a person when they are not given enough food of any sort.

The effects of Malnutrition /Starvation include:

- Slow growth

- Fatigue

- Poor resistance to infection

- Irregular periods (in women)

111 of 212

Water Content

Why is it important to regulate the water content in the body?

112 of 212

A Sense Organ

A sense organ is the organ which detects the stimulus these are:

- EYES

- EARS

- NOSE

- TONGUE

- SKIN

113 of 212

Cholesterol 2

What are HDLs (High Density lipo-proteins) and LDLs (Low Density lip-proteins)?

114 of 212

Cholesterol 1

What is Cholesterol?

115 of 212

A Receptor

What is a Receptor?

116 of 212

Cholesterol 1

Cholesterol is a fatty substance that's essential for good health - and it is found in every cell of the body.

However, a high cholesterol level is bad for your health, because blood vessels get clogged with fatty cholesterol deposits, and this reduces the blood flow to the heart. Reduced blood flow can lead to angina (chest pain) or even a heart attack!

The liver makes and removes this substance into and from the blood, however the amount it makes and removes depends on your health...

117 of 212

Cholesterol 2

Cholesterol is transported around the body in blood by lipoproteins.

High Density lipo-proteins (HDLs), carry cholesterol that isn't needed from the body cells back to the liver for removal from the body - so they're called 'good cholesterol'.

Low Density lipo-proteins (LDLs), carry cholesterol from the liver to the body cells - they're known as 'bad cholesterol' because any excess can build up in the arteries.

118 of 212

A Receptor

Receptors are groups of cells which are sensitive to a stimulus - they change stimulus energy into electrical impulses.

- EYES: Light receptors

- EARS: Sound and 'balance' receptors

- NOSE: Smell receptors (chemical stimuli)

- TONGUE: Taste receptors

- SKIN: Receptors sensitive to touch, pressure and temperature change

119 of 212

Cholesterol 2

What are HDLs (High Density lipo-proteins) and LDLs (Low Density lip-proteins)?

120 of 212

Cholesterol 3

What are Saturated Fats, Polyunsaturated Fats, and Monounsaturated Fats?

121 of 212

A Stimulus

What is a Stimulus?

122 of 212

Cholesterol 3

Saturated Fats: These fats contain no double carbon bond - they raise cholesterol in the blood, by increasing the amount the blood makes, and decreasing the amount it gets rid of (should be eaten in moderation).

Polyunsaturated Fats: These fats contain more than one double carbon bond - they tend to lower blood cholesterol, by increasing its removal from the body, and improving the LDL/HDL balance.

Monounsaturated Fats: These fats contain exactly one double carbon bond - they are considered as 'neutral' as far as health is concerned. However, recent evidence has suggested that they can help to lower blood cholesterol and improve the LDL/HDL balance.

123 of 212

Cholesterol 2

Cholesterol is transported around the body in blood by lipoproteins.

High Density lipo-proteins (HDLs), carry cholesterol that isn't needed from the body cells back to the liver for removal from the body - so they're called 'good cholesterol'.

Low Density lipo-proteins (LDLs), carry cholesterol from the liver to the body cells - they're known as 'bad cholesterol' because any excess can build up in the arteries.

124 of 212

A Stimulus

A stimulus is a change in your environment, which you may need to react to (e.g. a recently pounced tiger).

125 of 212

Cholesterol 3

What are Saturated Fats, Polyunsaturated Fats, and Monounsaturated Fats?

126 of 212

A Sensory Neurone

What is a Sensory Neurone?

127 of 212

Drugs

A drug is a chemical or substance which alters the way the body or mind function, they are derived from natural substances found in plants. Some of the chemical changes which happen because of a drug can cause the person to become addicted. If this drug isn't taken reguarly, the addict can suffer withdrawal symptoms.

Medical drugs have to be thoroughly tested, and go through a thorough testing procedure of four stages:

- First step: Computer models (they stimulate a human's response to a drug).

- Second step: The drug is then developed further by testing on human tissue in the lab.

- Third step: To develop and test the drug using live mammals.

- Fourth step: To finally test the drug on human volunteers.

128 of 212

Cholesterol 3

Saturated Fats: These fats contain no double carbon bond - they raise cholesterol in the blood, by increasing the amount the blood makes, and decreasing the amount it gets rid of (should be eaten in moderation).

Polyunsaturated Fats: These fats contain more than one double carbon bond - they tend to lower blood cholesterol, by increasing its removal from the body, and improving the LDL/HDL balance.

Monounsaturated Fats: These fats contain exactly one double carbon bond - they are considered as 'neutral' as far as health is concerned. However, recent evidence has suggested that they can help to lower blood cholesterol and improve the LDL/HDL balance.

129 of 212

Thalidomide

What is Thalidomide and what were the problems with it?

130 of 212

A Sensory Neurone

Sensory neurones are the nerve cells that carry signals as electrical impulses from the receptors in the sense organs to the CNS (central nervous system).

131 of 212

Drugs

What are drugs, and what is done to make sure they are safe?

132 of 212

Thalidomide

Thalidomide was a drug developed in the 1950s, and was intended as a sleeping pill. But later it was seen as an effective drug in relieving sickness in pregnant women.

However, Thalidomide had not been tested as a drug for morning sickness, and consequently, people did not know the effects as a drug on pregnant women.

10,000 babies were affected by Thalidomide, and only about half of them survived - Thalidomide was later realised that it could pass through the placenta and affect the fetus, cauding stunted growth of the fetus' arms and legs.

The drug was banned, and rigorous testing procedures were introduced, it has now been re-introduced as treatment for leprosy, AIDS, and certain cancers, but can not be used on pregnant women.

133 of 212

A Motor Neurone

What is a Motor Neurone?

134 of 212

Drugs

A drug is a chemical or substance which alters the way the body or mind function, they are derived from natural substances found in plants. Some of the chemical changes which happen because of a drug can cause the person to become addicted. If this drug isn't taken reguarly, the addict can suffer withdrawal symptoms.

Medical drugs have to be thoroughly tested, and go through a thorough testing procedure of four stages:

- First step: Computer models (they stimulate a human's response to a drug).

- Second step: The drug is then developed further by testing on human tissue in the lab.

- Third step: To develop and test the drug using live mammals.

- Fourth step: To finally test the drug on human volunteers.

135 of 212

Alcohol and Tobacco

What are the effects of Tobacco on the human body?

136 of 212

Motor Neurones are the nerve cells that carry signals from the CNS to the effector (muscle or gland).

137 of 212

Thalidomide

What is Thalidomide and what were the problems with it?

138 of 212

Alcohol and Tobacco

TOBACCO:

- Carbon Monoxide: Cobines with Haemoglobin in blood cells - body deprived of Oxygen.

- Tobacco smoke contains carcinogens - chemicals that cause cancer.

- Smoking causes disease of the heart and blood vessels - leading to heart attacks and strokes. This leads to diseases like emphysema and bronchitis.

- The tar in cigarettes damages the cilia (little hairs) in your lunngs and windpipe. These hairs, along with mucus, catch a load of dust and bacteria before they reach the lungs, without them, chest infections are more likely.

- Smoking tobacco is also addictive - due to the nicotine in tobacco smoke.

139 of 212

The Central Nervous System (CNS)

What is the Central Nervous System?

140 of 212

Thalidomide

Thalidomide was a drug developed in the 1950s, and was intended as a sleeping pill. But later it was seen as an effective drug in relieving sickness in pregnant women.

However, Thalidomide had not been tested as a drug for morning sickness, and consequently, people did not know the effects as a drug on pregnant women.

10,000 babies were affected by Thalidomide, and only about half of them survived - Thalidomide was later realised that it could pass through the placenta and affect the fetus, cauding stunted growth of the fetus' arms and legs.

The drug was banned, and rigorous testing procedures were introduced, it has now been re-introduced as treatment for leprosy, AIDS, and certain cancers, but can not be used on pregnant women.

141 of 212

Alcohol and Tobacco

What are the effects of Alcohol on the human body?

142 of 212

The Central Nervous System (CNS)

The Central Nervous System (CNS), is where all the information from the sense organs is sent, and where reflexes and actions are coordinated. The CNS consists of the brain and spinal cord only.

143 of 212

Alcohol and Tobacco

What are the effects of Tobacco on the human body?

144 of 212

Alcohol and Tobacco

ALCOHOL:

- The main affect of alcohol is that it reduces the activity of the nervous system -slowing down your reactions.

- It also makes you feel less inhibited - helping you to socialise and relax.

- Too much tobacco can lead to impaired judgement, poor balance and coordination, lack of self-control, unconsciousness and even coma.

- Excess alcohol can also cause dehydration - this can damage brain cells.

- There are also social costs too, alcohol is linked with way more than half of murders, stabbings and domestic assaults.

145 of 212

A Synapse

What is a Synapse?

146 of 212

Alcohol and Tobacco

TOBACCO:

- Carbon Monoxide: Cobines with Haemoglobin in blood cells - body deprived of Oxygen.

- Tobacco smoke contains carcinogens - chemicals that cause cancer.

- Smoking causes disease of the heart and blood vessels - leading to heart attacks and strokes. This leads to diseases like emphysema and bronchitis.

- The tar in cigarettes damages the cilia (little hairs) in your lunngs and windpipe. These hairs, along with mucus, catch a load of dust and bacteria before they reach the lungs, without them, chest infections are more likely.

- Smoking tobacco is also addictive - due to the nicotine in tobacco smoke.

147 of 212

Fighting Disease 1

What is bacteria and virus, and what does it do?

148 of 212

A Synapse

A Synapse is the 'junction' between two neurones. The nerve signal is transferred by chemicals which diffuse (move) across the gap - which then set off a new electrical signal in the next neurone.

149 of 212

Alcohol and Tobacco

What are the effects of Alcohol on the human body?

150 of 212

Fighting Disease 1

Bacteria:

Bacteria are very small living cells, which can reproduce rapidly inside your body.

Bacteria makes you feel ill by doing two things; a) Damaging your cells b) Producing toxins

Virus:

Viruses are not cells, they're about 100 times smaller than a bacteria cell. They're no more than a coat of protein around some genetic material.

Viruses replicate themselves by invading your cells and using the cells' machinery to produce many copies of themselves. The cell will then burst, releasing the virus into the body.

The cell damage is what makes you feel ill.

151 of 212

A Reflex Arc

What is a Reflex Arc?

152 of 212

Malnutrition/Starvation

Malnutrition, is the condition of a person when they are given a lack of one of more types of foods.

Starvation is the condition of a person when they are not given enough food of any sort.

The effects of Malnutrition /Starvation include:

- Slow growth

- Fatigue

- Poor resistance to infection

- Irregular periods (in women)

153 of 212

A Reflex Arc

The reflex arc is the passage of information in a reflex action (from receptor to effector). We have reflex actions because sometimes waiting for your brain to make a decision is too slow, therefore we have automatic responses to certain stimuli - and they reduce the risks of us being injured.

Here is a diagram to display a reflex arc:

Stimuli>Receptor>Sensory Neurone>Relay Neurone>Motor Neurone>Effector>Response

154 of 212

Fighting Disease 1

What is bacteria and virus, and what does it do?

155 of 212

A Hormone

What is a hormone?

156 of 212

Fighting Disease 1

Bacteria:

Bacteria are very small living cells, which can reproduce rapidly inside your body.

Bacteria makes you feel ill by doing two things; a) Damaging your cells b) Producing toxins

Virus:

Viruses are not cells, they're about 100 times smaller than a bacteria cell. They're no more than a coat of protein around some genetic material.

Viruses replicate themselves by invading your cells and using the cells' machinery to produce many copies of themselves. The cell will then burst, releasing the virus into the body.

The cell damage is what makes you feel ill.

157 of 212

A Hormone

Hormones are chemical messengers which travel in the blood to activate target cells.

158 of 212

Cholesterol 1

Cholesterol is a fatty substance that's essential for good health - and it is found in every cell of the body.

However, a high cholesterol level is bad for your health, because blood vessels get clogged with fatty cholesterol deposits, and this reduces the blood flow to the heart. Reduced blood flow can lead to angina (chest pain) or even a heart attack!

The liver makes and removes this substance into and from the blood, however the amount it makes and removes depends on your health...

159 of 212

The Pituitary Gland

The pituitary gland is located just below the brain, and produces many important hormones including LH (luteinising hormone), FSH (follicle-stimulating hormone) and ADH (controls water content).

160 of 212

The Pancreas

What is the Pancreas?

161 of 212

The Pancreas

The Pancreas is located just infront of the kidneys, and produces insulin for the control of the blood sugar levels in the body.

162 of 212

The Ovaries

What are the Ovaries?

163 of 212

The Ovaries

Ovaries are within females only, and they produce Oestrogen which controls the Menstrual Cycle. Ovaries also promote all female secondary characteristics such as extra body hair, and widening of the hips.

164 of 212

The Testes

What are the Testes?

165 of 212

The Testes

Testes appear in men only, and they produce testosterone which promotes all male secondary sexual characteristics at puberty e.g. extra body hair.

166 of 212

FSH (Follice-stimulating hormone)

What is FSH?

167 of 212

FSH (Follice-stimulating hormone)

FSH (Follice-stimulating hormone), is produced by the pituitary gland, and causes an egg to mature in one of the ovaries, as well as stimulating the ovaries to produce Oestrogen.

168 of 212

FSH (Follice-stimulating hormone) 2

How can FSH increase the chances of pregnancy?

169 of 212

FSH (Follice-stimulating hormone) 2

Low levels of FSH mean that there is not enough of the hormone to mature the eggs in the ovaries. Consequently, no eggs are released at the middle of the Menstrual Cycle, and this means that the woman can not get pregnant. Therefore, this hormone can be taken by women to stimulate the production of eggs in the ovaries.

Increased levels of FSH also mean that ovaries are stimulated to produce LH (luteinising hormone), which means your ovaries are stimulated to release eggs.

ADVANATGES - Help women get pregnant

DISADVANTAGES - This process does not always work. Also, sometimes, too many eggs could be stimulated - increasing the chances of multiple births.

170 of 212

Oestrogen

What is Oestrogen?

171 of 212

Oestrogen

Oestrogen is produced in the ovaries, and causes the pituitary gland to produced LH (luteinising hormone), as well as inhibiting any further release of FSH (follicle-stimulating hormone).

172 of 212

LH (Luteinising hormone)

What is LH?

173 of 212

LH (Luteinising hormone)

LH, is the hormone produced in the pituitary gland, and it stimulates the release of an egg at around the middle of the Menstrual Cycle.

174 of 212

The Pill

What is the Pill?

175 of 212

The Pill

The Pill is an oral contraceptive, which contains Oestrogen. It works by ihibiting the release of FSH, and if the levels of Oestrogen are kept permanatly high, after a while, egg development and production stops and stays stopped.

ADVANTAGES: Over 99% effective, and it reduces the risk of getting some types of cancer.

DISADVANTAGES: Side effects include headaches, nausea and irregular bleeding, and The Pill doesn't protect again sexually transmitted diseases (STDs).

176 of 212

IVF (in vitro fertilisation)

What is IVF?

177 of 212

A Sensory Neurone

What is a Sensory Neurone?

178 of 212

Homeostasis

What is Homeostasis?

179 of 212

Homeostasis

Homeostasis is the process in which all the functions of the body try to maintain a 'constant internal environment'. The bodily levels which need to be controlled are:

- Ion Content

- Water Content

- Sugar Content

- Temperature

180 of 212

Ion Content

Why is it important to regulate the ion content?

181 of 212

Ion Content

Ion content is regulated by the kidneys. Ions (e.g. sodium) is taken into the body through food. If the food contains too much of any kind of ion, then the excess ions need to be removed. Ions are lost in sweat, as well as removed by the kidneys in urin.

182 of 212

Water Content

Why is it important to regulate the water content in the body?

183 of 212

Water Content

Water is taken into the body with food and drink, and is lost from the body in these ways:

- Through the skin as sweat

- Via the lungs in breath

- Via the kidneys as urine

184 of 212

Body Temperature

Why is it important to regulate the body temperature?

185 of 212

Body Temperature

All enzymes work best at 37 degrees, and therefore your body aims to maintain this temperature. A part of your brain acts as your own personal thermostat, and is sensitive to the blood temperature.

186 of 212

Blood Sugar

Why is it important to regulate the blood sugar levels?

187 of 212

Blood Sugar

Sugar is taken into the body through carbohydrate foods. Metabolism of cells removes glucose from the blood, and so does a balanced daily amount of exercise. However, to maintain the right level, we have the hormone insulin - which removes sugar from our blood. Diabetes (Type 1) is an illness at which your body doesn't produce enough insulin to maintain the correct blood sugar level.

188 of 212

A Balanced Diet

What are the five groups, and their roles?

189 of 212

A Balanced Diet

- Carbohydrates and fats: Keep you warm and provide energy

- Protein: For growth, cell repair and cell replacement

- Fibre: Keep everything moving smoothly in your digestive system

- Vitamins and minerals: Maintain the healthiness of the blood, skin and bones

190 of 212

Metabolism

What is the Metabolism?

191 of 212

Metabolism

The Metabolism is the chemical reactions which happen within the body to keep you alive. The Metabolic Rate is the speed at which these reactions occur. People with higher proportions of muscle to fat, will have a higher Metabolic Rate.

Regular exercise can boost your resting Metabolic Rate.

192 of 212

Obesity

What is Obesity and what are its effects?

193 of 212

Obesity

Obesity is the condition at which people become severely overweight, and this can happen because of bad diet, overeating, lack of exercise, or even hormonal problems.

Health problems caused because of obesity include:

- Arthritis (inflamation of the joints)

- Diabetes (inability to control blood sugar levels)

- High blood pressure

- Heart Disease

- Some types of cancer

194 of 212

Malnutrition/Starvation

What is Malnutrition/Starvation, and what are the effects of each of them?

195 of 212

Malnutrition/Starvation

Malnutrition, is the condition of a person when they are given a lack of one of more types of foods.

Starvation is the condition of a person when they are not given enough food of any sort.

The effects of Malnutrition /Starvation include:

- Slow growth

- Fatigue

- Poor resistance to infection

- Irregular periods (in women)

196 of 212

Alcohol and Tobacco

ALCOHOL:

- The main affect of alcohol is that it reduces the activity of the nervous system -slowing down your reactions.

- It also makes you feel less inhibited - helping you to socialise and relax.

- Too much tobacco can lead to impaired judgement, poor balance and coordination, lack of self-control, unconsciousness and even coma.

- Excess alcohol can also cause dehydration - this can damage brain cells.

- There are also social costs too, alcohol is linked with way more than half of murders, stabbings and domestic assaults.

197 of 212

Cholesterol 1

Cholesterol is a fatty substance that's essential for good health - and it is found in every cell of the body.

However, a high cholesterol level is bad for your health, because blood vessels get clogged with fatty cholesterol deposits, and this reduces the blood flow to the heart. Reduced blood flow can lead to angina (chest pain) or even a heart attack!

The liver makes and removes this substance into and from the blood, however the amount it makes and removes depends on your health...

198 of 212

Cholesterol 2

What are HDLs (High Density lipo-proteins) and LDLs (Low Density lip-proteins)?

199 of 212

Cholesterol 2

Cholesterol is transported around the body in blood by lipoproteins.

High Density lipo-proteins (HDLs), carry cholesterol that isn't needed from the body cells back to the liver for removal from the body - so they're called 'good cholesterol'.

Low Density lipo-proteins (LDLs), carry cholesterol from the liver to the body cells - they're known as 'bad cholesterol' because any excess can build up in the arteries.

200 of 212

Cholesterol 3

What are Saturated Fats, Polyunsaturated Fats, and Monounsaturated Fats?

201 of 212

Cholesterol 3

Saturated Fats: These fats contain no double carbon bond - they raise cholesterol in the blood, by increasing the amount the blood makes, and decreasing the amount it gets rid of (should be eaten in moderation).

Polyunsaturated Fats: These fats contain more than one double carbon bond - they tend to lower blood cholesterol, by increasing its removal from the body, and improving the LDL/HDL balance.

Monounsaturated Fats: These fats contain exactly one double carbon bond - they are considered as 'neutral' as far as health is concerned. However, recent evidence has suggested that they can help to lower blood cholesterol and improve the LDL/HDL balance.

202 of 212

Drugs

What are drugs, and what is done to make sure they are safe?

203 of 212

Drugs

A drug is a chemical or substance which alters the way the body or mind function, they are derived from natural substances found in plants. Some of the chemical changes which happen because of a drug can cause the person to become addicted. If this drug isn't taken reguarly, the addict can suffer withdrawal symptoms.

Medical drugs have to be thoroughly tested, and go through a thorough testing procedure of four stages:

- First step: Computer models (they stimulate a human's response to a drug).

- Second step: The drug is then developed further by testing on human tissue in the lab.

- Third step: To develop and test the drug using live mammals.

- Fourth step: To finally test the drug on human volunteers.

204 of 212

Thalidomide

What is Thalidomide and what were the problems with it?

205 of 212

Thalidomide

Thalidomide was a drug developed in the 1950s, and was intended as a sleeping pill. But later it was seen as an effective drug in relieving sickness in pregnant women.

However, Thalidomide had not been tested as a drug for morning sickness, and consequently, people did not know the effects as a drug on pregnant women.

10,000 babies were affected by Thalidomide, and only about half of them survived - Thalidomide was later realised that it could pass through the placenta and affect the fetus, cauding stunted growth of the fetus' arms and legs.

The drug was banned, and rigorous testing procedures were introduced, it has now been re-introduced as treatment for leprosy, AIDS, and certain cancers, but can not be used on pregnant women.

206 of 212

Alcohol and Tobacco

What are the effects of Tobacco on the human body?

207 of 212

Alcohol and Tobacco

TOBACCO:

- Carbon Monoxide: Cobines with Haemoglobin in blood cells - body deprived of Oxygen.

- Tobacco smoke contains carcinogens - chemicals that cause cancer.

- Smoking causes disease of the heart and blood vessels - leading to heart attacks and strokes. This leads to diseases like emphysema and bronchitis.

- The tar in cigarettes damages the cilia (little hairs) in your lunngs and windpipe. These hairs, along with mucus, catch a load of dust and bacteria before they reach the lungs, without them, chest infections are more likely.

- Smoking tobacco is also addictive - due to the nicotine in tobacco smoke.

208 of 212

Alcohol and Tobacco

What are the effects of Alcohol on the human body?

209 of 212

Alcohol and Tobacco

ALCOHOL:

- The main affect of alcohol is that it reduces the activity of the nervous system -slowing down your reactions.

- It also makes you feel less inhibited - helping you to socialise and relax.

- Too much tobacco can lead to impaired judgement, poor balance and coordination, lack of self-control, unconsciousness and even coma.

- Excess alcohol can also cause dehydration - this can damage brain cells.

- There are also social costs too, alcohol is linked with way more than half of murders, stabbings and domestic assaults.

210 of 212

Fighting Disease 1

What is bacteria and virus, and what does it do?

211 of 212

Fighting Disease 1

Bacteria:

Bacteria are very small living cells, which can reproduce rapidly inside your body.

Bacteria makes you feel ill by doing two things; a) Damaging your cells b) Producing toxins

Virus:

Viruses are not cells, they're about 100 times smaller than a bacteria cell. They're no more than a coat of protein around some genetic material.

Viruses replicate themselves by invading your cells and using the cells' machinery to produce many copies of themselves. The cell will then burst, releasing the virus into the body.

The cell damage is what makes you feel ill.

212 of 212

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all resources »