The contraction of heart muscles forces the blood through arteries under pressure.
Measured in mmHg
2 measurements of blood pressure:
-Systolic pressure is the maximum pressure the heart produces.
-Diastolic is the pressure between the heart beats.
*Increase: high alcohol intake/smoking/stress/unbalanced diet
*Decrease: exercise/balanced diet
Fitness and health
Fitness: The ability to be able to do physical activity
Health: Being free from disease caused by viruses or bacteria
*Fitness can be measured in cardiovascular efficiency
INCREASES BLOOD PRESSURE
-carbon monoxide in the smoke can cause blood to carry less oxygen meaning the heart rate will increase so that the tissues receive enough oxygen
-Also nicotine itself increases the heart rate
The smoke contains chemicals that stops cilia moving. Cilia are tiny hairs that are found in the epithelial lining of the trachea, bronchi and bronchioles.
Dust and particles are in smoke are collecting and irritating the epithelial lining.
Also mucus is not being moved by the cilia
Diet and heart disease
*Heart disease is caused by a restricted blood flow to the heart muscle which is increased by saturated fats which leads to a build up of cholesterol (a plaque) on the arteries.
Increase of heart disease:
-high blood pressure
-high levels of salts
Blood pressure is increased by:
-high levels of salt
Should consist of:
-protein= growth and repair
-carbohydrates= energy source
-fats= energy source
-minerals= to make haemoglobin
-vitamins= to prevent scurvy (vitamin c)
-fibre= to stop constipation
-water= keep hydrated
3 chemicals needed found in food
*amino acids (protein)
*fatty acids and glycerol
Proteins are needed for growth so we need to eat the corrects amount. Our EAR will tell us our intake needed.
Formula: EAR in g= 0.6 X body mass in kg
High protein foods are expensive and short supply so in poorer countries their diets are deficient in protein. This could cause a disease called Kwashiorkor
To work out if someone's overweight or underweight, you calculate their BMI
BMI= Mass in kg/(Height in m)*
- means squared
Fight against illness
Pathogens produce symptoms of an infectious diseases by damaging the body cells or just by producing a poisonous waste products called toxins.
Antibodies will kill the pathogen by locking onto antigens which is on the surface of a pathogen. .White blood cells are what produces the antibodies, resulting in active immunity
Malaria is caused by a protozoan called plasmodium that feeds on red blood cells.
-carried by mosquitoes which is a vector
-it's a parasite and the human is the host
a parasite is a living organism that feeds off another living organism, causing it harm.
Treatment and trials
Tested on animals/human tissues/computer models before human trials!!
Antibiotics: against fungi and bacteria, it destroys the pathogen
Antiviral drugs:against viruses, slows down the pathogens development
Parts of the eye
Coloured Iris: controls amount of light that enters eye
Pupil: Allows light rays to enter eye
Cornea: Refracts (bends) light rays
Cillary Muscle: Conrols suspensory ligaments
Lens: Refracts (bends) light rays and focuses light onto retina. Long sighted or short sighted when lens is wrong shape
Retina: where focused image forms, has light receptors, some are sensitive to some colours. Causes colour blindness when lack of specialised cells.
Optic nerve: Carries nerve impulses to brain
Suspensory Ligaments: Alters shape opf lens when focusing
Binocular vision helps judge distance by comapring the 2 images from each eye, the more different the image the closer the object is.
B1 FLASH CARDS
Nerve impulses (electrical signals) pass through the axon in a neurone.
A reflext action is shown by a reflex arc. The links in a reflex arc are:
stimulus-receptor-sensory neurone-central nervous system-motor neurone-effector-response
Pathway for a spinal reflex:
receptor-sensory neurone-relay neurone-motor neurone-effector
Depressants- slows down the brain activity (Alcohol)
Pain killers- Block nerve impulses (aspirin/paracetamol)
Stimulants- increases brain activity (nicotine/MDMA/caffeine)
Performance enhancers- increase muscle development (anabolic steroids)
Hallucinogens- distorts what is seen or heard (LSD)
Plant hormone- Auxin
Auxin is made in the tip of the plant
Phototropism- plant growth response towards the light
Geotropism-plant growth response towards the gravity
(Negative and positive)
Plant hormones are used in agriculture to speed up or down plant growth
The hormone can be used:
~as weed killer
~as a rooting powder when taking cuttings
~to control dormancy in seeds
~to delay fruit ripening
Human characteristic can be inherited or an environmental factor
-domainant or recessive
Alleles:different versions of the same gene
Humans have 23 pairs
Genetic variation is caused by:
-mutation (random changes in genes or chromosomes)
-rearrangement of genes during the formations of garmetes
-fertilisation (results in zygote from the fathers and mother)
Alcohol increases reaction times and increases accidents
Short term effects: blurred vision/slurred speech/increased blood flow to skin
Long term effects: liver and brain damage
Homeostasis- keeping constant internal environment
-involves balancing bodily inputs and outputs
Automatic control systems keeps the levels of water, temperature and carbon dioxide steady. To make sure cells can work at their optimum level
37 Degrees is this regular body temperature
High temperature can cause:
CAN BE FATAL IF NOT TREATED
Avoid overheating,sweating increases heat transfer from the body to the environment. Evaporation of sweat require body to change liquid sweat into water vapour
Low temperature can cause:
CAN BE FATAL IF NOT TREATED
Blood sugar levels
Pancreas produce the hormone insulin
-insulin controls blood sugar levels
Type 1 diabetes: pancreas can't produce insulin
Type 2 diabetes: the body produces very little insulin or the body can't react to it can be controlled by diet