Biology Unit 3 (May 2013)
4.0 / 5 based on 3 ratings
- Created by: Esme
- Created on: 11-05-13 15:25
What is osmosis?
The movement of water particles through a partially permeable membrane from a high concentration to low concentation
1 of 86
What moves water in and out of cells?
Osmosis
2 of 86
What is the size of the stomata controlled by?
Guard cells
3 of 86
What happens when there's no guard cells?
The plant wilts
4 of 86
What makes evaporation quicker?
It being hot, dry and windy
5 of 86
What are neuphrons
Filtration units in the kidneys
6 of 86
What is ultrafiltration in the kidney?
Building up pressure to squeeze water, urea, ions and sugar out of the blood and into Bowman's capsule. Proteins and blood cells can't escape
7 of 86
What is reabsorption in the kidney?
Reabsorbing sugar (active transport), sufficient ions (active transport) and sufficient water
8 of 86
What is release of wastes in the kidney?
Remaining substances after ultrafiltration and reabsorption continues out of the neuphron, into ureter and bladder as urine.
9 of 86
What are the disadvantages of dialysis?
3 times a week for 3-4 hours at a time, blood clots & infections
10 of 86
Overall what does dialysis do?
Keeps concentration of dissolved substances in the blood at normal levels & to remove waste substances
11 of 86
In a kidney transplant, what helps to stop rejection?
Choosing a kidney with similar tissue types and patient given drugs to suppress immune system
12 of 86
What makes red blood cells effective?
Large SA, no nucleus, haemoglobin to combine with oxygen to become oxyhaemoglobin
13 of 86
What do white blood cells do?
Engulf unwanted microorganisms, produce antibodies (to fight) and antitoxins (neutralise toxins)
14 of 86
What are platelets and what do they do?
Help clotting, are small fragments of cells, no nucleus. Stop microorganisms getting into the wound
15 of 86
What is plasma?
Carries everything in blood e.g. red&white blood cells, platelets, nutrients, CO2, urea, hormones, antibodies, antitoxins
16 of 86
What is artificial blood used for?
Keep you alive in emergencies
17 of 86
What is saline (artificial blood) used for?
To replace lost volume of blood, and give patient time to make new blood cells
18 of 86
What is an artificial heart?
A mechanical device put in to pump blood - temporary until donor heart can be found
19 of 86
What is an advantage of an artificial heart?
It's not rejected by the person's immune system
20 of 86
What are some disadvantage of an artificial heart?
Surgery can lead to bleeding and infection, blood doesn't flow through smoothly (can lead to clots and strokes), patients must take pills to thin blood which leads to problems when bleeding
21 of 86
What do stents do?
Keep arteries open, which stops coronary heart disease because they allow blood to flow properly
22 of 86
What are the 3 main roles of the kidney in homeostatis?
1. Removal of urea, 2. adjustment of ions, 3. adjustment of water
23 of 86
How does the kidney remove urea? How did urea get into the blood?
Urea is a waste product of the liver converting amino acids into fats and carbs. Urea is poisonous, it's released into the blood stream by the liver. The kidneys filter it from the blood, then temporarily stored in the bladder as urine.
24 of 86
Why would the wrong ion content be bad? What do the kidneys do?
Upsets ion/water balance so excess ions are removed by the kidneys, sometimes lost in sweat
25 of 86
In what 3 main ways is the water lost in the body?
1. Urine 2. sweat 3. breathing out
26 of 86
What does a cold day mean for sweat and urine?
No sweat, more urine - which is pale and dilute
27 of 86
What does a hot day mean for sweat and urine?
More sweat, less urine - which is dark and concentrated
28 of 86
What do sports drinks replace?
Water, sugar and ions lost in sweat and muscles during excersize
29 of 86
Define homeostatis
The maintenance of a Constant Internal Environment
30 of 86
In homeostatis, what 6 things need to be controlled?
1. Temperature 2. water 3. ions 4. blood sugar 5. carbon dioxide 6. urea
31 of 86
What temperature do enzymes work best at in humans?
37°C
32 of 86
In the brain, what contains receptors sensitive to blood temperature?
The thermo-regulatory centre
33 of 86
What happens to your body when it's too hot?
Hair lies flat, sweat produced, evaporation off skin, blood vessels dilate (so more blood goes to the surface of the skin and heat can be transferred from blood to the environment)
34 of 86
What happens to your body when it's too cold?
Hair stand up (to trap an insulating layer of air), no sweat, blood vessels constrict to close off the skin's blood supply, you shiver (it needs respiration which releases energy to warm the body)
35 of 86
What are batch generators?
They produce small batches of biogas, manually loaded, by-products cleared after each session.
36 of 86
What are continuous generators?
Non-stop, waste continuously fed in, biogas is produced at a steady rate
37 of 86
What are the 4 factors to consider when building a biogas generator?
Cost, convenience, efficiency, position
38 of 86
What are the economic and environmental effects of biogas energy?
'Greener' than fossil fuels, carbon neutral, raw material is cheap and readily available, digested material is a good fertiliser
39 of 86
What process can make fuels?
Fermentation
40 of 86
What is fermentation?
When bacteria or yeast breaks sugar down by anaerobic respiration
41 of 86
Ethanol is the fermention of what?
Sugar
42 of 86
Biogas is the fermentation of what?
Waster materials - usually 70% methane, 30% carbon dioxide
43 of 86
How can the efficiency of food production be improved?
Reducing stages in food chain (less energy and biomass after every stage), feed more people on growing crops, restricting energy lost by warm animals - animals are intensively farmed, developing new food sources like mycoprotein
44 of 86
What does intensive farming mean?
Keep animals in close indoor conditions which stops them wasting energy in movement and heat, animals grow
45 of 86
What is microprotein? What is it used for?
Protein from fungi, to make meat substitues.
46 of 86
What fungus is the main source of microprotein?
Fusarium
47 of 86
How is the fungus turned into a meat substitute?
It is grown in fermenters using glucose syrup, the fungus respires aerobically so oxygen is supplied
48 of 86
What are the advantages of mycoprotein?
Mycoprotein in a fermenter is an efficient way of producing protein, microorganisms grow quickly in little space and can feed on waster material
49 of 86
What are some arguments against intensive farming?
Conditions are cruel - there is a growing demand for organic meat, conditions mean diseases spread quickly, fish stocks are getting low
50 of 86
What are the problems with food miles? What are they?
They are miles used up in transporting food products by planes, ships and trucks, they all burn scarce fossil fuels and release CO2, contributing to global warming
51 of 86
How is overfishing reduced?
Fishing quotas (limits to number & size of fish), control in net size - reduces number of unwanted and discarded fish
52 of 86
What are some consequences of climate change?
1. Sea warms up, expands, levels rise, low lying place flood permanently 2. higher temperature = ice melting, levels rice even more 3. change in weather patterns hard to predict 4. distribution of plants & animals could change 5. reduced biodiversity
53 of 86
How is climate change monitored?
Satellites, to monitor snow and ice cover and measure the temperature of the sea surface
54 of 86
What do the lungs do in the double circulatory system?
Deoxygenated blood is taken to lungs to take in oxygen, then is taken back to the heart
55 of 86
What does the heart do in the double circulatory system?
Pumps deoxygenated blood to lungs, then pumps the returning oxygenated blood to other organs to be used up and deoxygenated blood is returned to the heart to start over
56 of 86
How does the heart work?
1.Blood flows into 2 atria from vena cava & pulmonary vein 2.atria contract, blood goes into ventricles 3. ventricles contract, blood goes into pulmonary artery & aorta (out of heart)
57 of 86
What are the three types of blood vessels?
Arteries, capillaries and veins
58 of 86
What do the arteries do? What are their features?
Carry high pressured blood away from the heart. Their walls are strong and elastic and thick, they contain thick layers of muscle. Quite a large lumen
59 of 86
What do the capillaries do? What are their features?
Help with exchange of materials at the tissue. They are really small (branched from arteries), carry blood really close to cells, have a permeable wall for faster diffusion. Supply O2 & food and take CO2 & waste. Walls are usually one cell thick
60 of 86
What do the veins do? What are their features?
Carry blood to the heart, joined from capillaries. Blood is carried at a lower pressure, so they have thinner walls than arteries. Bigger lumen to help blood flow. They have valves to keep blood flowing the right way.
61 of 86
If you have type 1 diabetes, what is your insulin level like?
Very low to none
62 of 86
How is type 1 diabetes controlled?
Avoiding foods rich in carbs, exercise after eating, inject insulin at mealtimes, can have a pancreas transplant but high rejection rates
63 of 86
What hormones are used by the pancreas to control glucose levels?
Insulin and glucagon
64 of 86
What hormones are added at different levels of glucose?
High levels = insulin. Low levels = glucagon
65 of 86
What is the thorax?
The top part of the body
66 of 86
Where are the lungs?
In the thorax
67 of 86
How does air get in to and move about in the lungs?
In through trachea, splits into 2 called bronchi, split into bronctricles, end at small bags called alveoli where gas exchange takes place
68 of 86
What is ventilitation?
The movement of air in to and out of the lungs
69 of 86
What happens when you breathe in?
Intercostal muscles & diaphragm contract, thorax volume increases, pressure decreases - letting air in
70 of 86
What happens when you breathe out?
intercostal muscles and diaphragm relax, thorax volume decreases, pressure increases - forcing air out
71 of 86
What are artificial ventilators?
Machines that move air into and out of the lungs
72 of 86
How do artificial ventilators work?
Pump air into the lungs, expanding the ribcage. When they stop pumping the ribcage relaxes and air is pushed back out
73 of 86
How to plants roots take in minerals?
Active transport - low to high concentrations. Against a concentration gradient
74 of 86
What do the phloem tubes do in the water flow through plants process?
Carry food. Are made of columns of living cells with small holes in the end. Transport food from leaves to growing regions and storage organs, transport in both directions
75 of 86
What do the xylem tubes do in the water flow through plants process?
Carry water. Are made of dead cells joined end to end with a hole in the middle They carry water and minerals from roots to stem and leave.
76 of 86
What is transpiration caused by in plants? What do they create?
Evaporation and diffusion in leaves, they create a constant transpiration stream
77 of 86
Where does gas exchange take place?
in the alveoli in the lungs
78 of 86
What is the job of the lungs?
Transfer oxygen to the blood and remove waster carbon dioxide.
79 of 86
How are alveoli specialised to maximise the rate of diffusion?
Big surface area, moist lining, very thing walls, good supply of blood
80 of 86
How are the villi adapted in the small intestine?
Big surface area so digested food is absorbed quickly into blood, have a single layer of surface cells, very good blood supply for quick absorption
81 of 86
What does too much carbon dioxide mean?
Global warming?
82 of 86
What can carbon dioxide be stored in?
oceans, lakes & ponds, green plants and peat bogs
83 of 86
How does human waste affect the water in the environment?
Sewage and toxic chemicals pollute lakes, rivers & oceans - affects plants and animals relying on them for survival, chemicals on land can be washed into water (fertilisers)
84 of 86
How does human waste affect the land in the environment?
We use toxic chemicals for farming, bury nuclear waste underground, household waste on land fills
85 of 86
How does human waste affect the air in the environment?
Smoke & gases are released into the atmosphere and can pollute air e.g. sulfur dioxide can cause acid rain
86 of 86
Other cards in this set
Card 2
Front
What moves water in and out of cells?
Back
Osmosis
Card 3
Front
What is the size of the stomata controlled by?
Back
Card 4
Front
What happens when there's no guard cells?
Back
Card 5
Front
What makes evaporation quicker?
Back
Related discussions on The Student Room
- Over 500 questions on AQA Bio Unit 4 + Current Spec and old Spec papers + MS! »
- A-level Exam Discussions 2024 »
- IAL repeats cash in. »
- Edexcel IAL results »
- GCSE Biology Study Group 2022-2023 »
- iria's 'grow your grades' blog :) »
- A Level Exam Discussions 2023 »
- I am looking at my GCSE grades from 2017 »
- Universities »
- BTEC Level 3 Applied Science Unit 1 May 2022 Exams »
Similar Biology resources:
0.0 / 5
0.0 / 5
0.0 / 5
0.0 / 5
0.0 / 5
0.0 / 5
5.0 / 5 based on 2 ratings
0.0 / 5
3.0 / 5 based on 1 rating
2.5 / 5 based on 3 ratings
Comments
Report
Report
Report