Structure and Function of Living Organisms

Explain why no droplets are seen after bile and lipase solution is added to the oil and water mixture

Bile emulsification

Smaller drops / increased surface area

Optimum pH

Lipase is an enzyme

Digests

Into fatty acids / glycerol

Explain how this structure (villus) is adapted to absorb glucose

Large surface area

Microvilli

Capillaries

Movement of blood to maintain concentration gradient

One cell thick

So diffusion easy

Active transport

Describe the role of chloroplasts in leaf cells

Trap/absorb light

Using chlorophyll

For photosynthesis to produce glucose/starch

Explain what happens in a leaf when it is destarched?

Starch is removed /used etc
converted to glucose

For respiration/energy

Describe how the green pigment is removed safely before testing a leaf for the presence of starch

Starch is removed /used etc

converted to glucose

For respiration/energy

Design an investigation to find out the effect of statins on blood cholesterol levels.

Change to type of statin used
Organism -- needs to be kept the same gender / age / mass / height / level of cholesterol
Repeat the test three times / use several people (group of people)
M1 measure cholesterol level
M2 at start and end
S1 + S2 same diet / mass of food / same stress / exercise / smoking

Describe how magnesium ions are used to help trees grow

For the chlorophyll in chloroplasts

To absorb light in photosynthesis

Which type of meat would provide the most energy?

The one with the most fat

Uses of fat in the human body

Energy

Protection/padding

Insulation

Cell membranes

Myelin sheath

Complete the table

Safety precautions for Benedict’s test

water bath / avoid direct heat / point away / eq;

goggles / lab coat / tongs / tie hair / tuck tie away / gloves;

(ii) Gazelles cannot maintain their top speed for a long time because a change in the type of respiration takes place in their muscle cells. Explain how this change in respiration stops gazelles from running at a top speed for a long time.

Anaerobic respiration

Uses less oxygen

Building up lactic acid

Denaturing the organism's enzymes

Providing less energy

Lion eyes have a layer of cells behind the retina that reflects light which has passed through the retina. Suggest how this would help a lion see in low light intensities.

Light passes through retina twice / more light through retina / more detection by retina / stimulation

Suggest adaption in structure of lion’s eye that helps the lion to see in low light intensities.

Light passes through retina twice / more light through retina / more detection by retina / stimulation

Suggest another adaption in structure of lion’s eye that helps the lion to see in low light intensities.

Dilated/larger pupil/ expanded pupil / more rods / larger hole in iris / radial muscles contract more

Suggest why saliva released into lion’s mouth does not contain amylase

Lion eats protein
Amylase cannot digest protein

Explain why there are no plasma proteins in urine

Protein molecules large /too big

Leave glomerulus /capillaries and enter Bowman's/renal capsule

Explain why there is no glucose in urine

Reabsorbed into blood

Through proximal/first/convoluted tubule

Through active transport

Name substances you would find in urine

Salts/minerals/ions/named mineral ion/hormones/vitamins

Urea
water

Suggest why a person with diabetes has glucose in their urine

No insulin

High blood glucose levels

Cannot reabsorb all glucose

ingestion

food enters the mouth

digestion

breaks down large insoluble molecules into smaller insoluble molecules

absorption

small food molecules move from small intestine into blood

assimilation

small food molecules are used to build large molecules

egestion

removal of undigested food / faeces / waste from anus

Draw + label phagocyte

Way structure of phagocyte differs from red blood cell

Nucleus/bigger/irregular/not biconcave

Describe how white blood cells are used by the body to defend against infection

1 ingest / engulf / surround / phagocytosis / eq;

2 enzymes;

3 digest / breakdown / eq;

4 lymphocytes;

5 antibodies / antitoxins;

6 specific / eq;

7 antigen:

8 memory / memory cell / eq;

Name A + B

Function of waxy cuticle

Reduce water loss / transpiration / evaporation / prevent entry of microorganisms

Explain how the excretory product of photosynthesis is removed from the leaf

Diffuses

Through stomata/pores/holes

Along concentration gradient

Reasons plants lose their leaves in cooler months

Reduce water loss

Less light

Less photosynthesis

Conserve energy

Which hormone repairs the uterus lining, and where is it produced?

oestrogen, ovaries

Suggest why cells do not store glucose

soluble
osmotic effect

Do fungi have a cell wall?

Yes

muscles that operate penguin’s feet located in penguin’s body rather than in feet. How does this benefit the penguin?

Muscles kept warm

Contract

Respiration

Enzymes at optimum tempearture

Describe how growth hormone could be destroyed in the stomach

hydrochloric acid

enzymes such as protease/pepsin

breakdown

and denature growth hormone

Describe how levels of blood glucose are kept constant in human plasma after eating a meal

Islets of langerhans in the pancreas

Release insulin

To lower levels of glucose

Storing it in form of glycogen

Ways in which nervous communication differs from hormonal communication

Neurones versus blood

Shorter lasting

Target cells (versus all around body)
Faster

Electrical vs chemical

Describe response of roots to gravity and explain how response benefits the plant

Positively geotropic (downward)

This allows roots to anchor the plant

Obtain water / mineral ions nutrients etc

What is B?

iris/cornea

What is mean the term population?

Number/amount/group of organisms of same species

Explain what is meant by the term hormone

Hormones are released from glands

Travel in blood

To target cells/organs

Causing an effect

Suggest why a person might produce hard lumpy faeces

Constipation
Lack of water
Lack of fibre

Why might a person produce watery faeces?

Diarrhoea

Less water absorbed

Food poisoning / infection

Describe how food is moved through the gut

Peristalsis

Contraction

Muscles

Pushed/squeezed

Explain how egestion differs from excretion

Faeces vs urea / excretory product

Undigested food vs metabolic waste product

Anus vs kidney/lung/skin

Not in cells vs in cells

Describe how the kidney machine removes urea from the blood

Diffusion

Along a partially permeable membrane

From high concentration to low concentration

Suggest how concentration of glucose in dialysis solution helps to maintain normal glucose concentration

same conc. in fluid and blood / normal blood conc.

in fluid / correct glucose conc. in fluid / eq;

if high in blood moves out of blood/into fluid;

if low in blood moves into blood/out of fluid;

Describe processes that take place in the kidney but not in the kidney machien

Ultrafiltration

Small molecules go out of blood / large molecules / protein stays in blood

Selective reabsorption of glucose/salts/water/amino acids

Active transport using energy from glucose

Suggest why the transplanted kidney is placed in the lower abdomen instead of in the kidney’s usual location

Nearer to bladder

Easier access

Easy to connect to blood vessels / shorter

What process takes part place at A?

Ultrafiltration

What process takes place at B?

Glucose reabsorption

Explain how the structure of the blood vessels entering and leaving the glomerulus help to move glucose into the Bowman’s capsule

Vessel entering is wider

Increased pressure

Allowing ultrafiltration

Describe how glucose is reabsorbed from the nephron back into the blood

Vessel entering is wider

Increased pressure

Allowing ultrafiltration

What is meant by the term gas exchange?

the absorption of oxygen and the removal of carbon dioxide

Suggest ways in which fish gills are adapted for efficient gas exchange

Large surface area

Thin

Large blood supply of capillaries

Permeable

What is C?

Heart

Describe how ribs and diaphragm help a person to breath inn

Diaphragm contracts

And moves down

Ribcage moves up

Increasing the thoraccic volume

Decreasing thoracic pressure

Suggest why people with cystic fibrosis often have lung infections

Bacteria/pathogens can

Reproduce and multiply in the lungs

Remaining there

Suggest why gas exchange is reduced in someone with cystic fibrosis

Less oxygen

Can get to the alveoli

Suggest and explain the effect of emphysema on gas exchange

Less surface area

Slower diffusion / gas exchange

Less oxygen

Explain how coronary heart disease can cause death

Coronary arteries

Blocked

By fat/cholesterol

Forming a clot

Getting less blood to the heart

And therefore oxygen

Causing the muscles

To have less respiration

Causing a build up of lactic acid and an angina

Resultign in heart attack

What is osmoregulation

Maintaining water/salt concentration of body

Where are villi located?

On the small intestine

What is cell X?

Leaf

How do palisade mesophyll cells help the leaf in photosynthesis?

Densely packed

With lots of chloroplasts

To take in light

How does the spongy layer help the leaf in photosynthesis

Has air spaces

For diffusion/gas exchange

Xylem

Can transport water

How do the guard cells help the leaf in photosynthesis

Open and close

To let in carbon dioxide

Water lilies float on surface, guard cells found on upper surface of water lilly. Suggest a reason for this adaption

Upper surface exposed to air

Allows carbon dioxide in

Allows transpiration

Suggest why red onion used for viewing cells

Easier to see / no need to stain contrast

Explain how the rate of transpiration is affected by changes in the environment

High humidity decreases rate

Reduced concentration gradient

High wind increases rate

Increased concentration gradient

High temperature increases rate

More kinetic energy

High light increases rate

Stomata open

Explain how this experiment can be used to understand the need for transport systems in larger organisms such as humans

Humans have smaller SA:V ratio

Therefore diffusion

Is too slow

Need to move nutrients

In circulatory system

Explain how the structure of the leaf is adapted for its role as the organ of photosynthesis

large surface area;

thin (leaf);

upper epidermis / cuticle;

transparent / lets light through;

chloroplasts / chlorophyll;

palisade (mesophyll);

close to surface;

absorb light;

spongy (mesophyll);

diffusion;

stomata / guard cells;

carbon dioxide;

xylem;

water; ignore if transpired

Explain how the rate of photosynthesis is affected by changes to abiotic factors throughout the day

Two from:

1. temperature

2. light (intensity)

3. carbon dioxide /

CO2;;

Then:

4. indication of level of

abiotic factor during the day;

5. stated effect on rate of photosynthesis;

Explain how very high temperatures might reduce the growth of plants

1. less photosynthesis;

2. (more) transpiration /

evaporation /loss of water / eq;

3. wilting / loss of turgor /

stomata close /

less mineral ion transport;

4. less carbon dioxide uptake;

5. enzymes denature /

change in shape of active site / eq;name

Name the two parts of a plant cell where most water is found

Cytoplasm

Vacuole

What are nitrate ions used for in plants?

Amino acids

Growth

DNA bases

Chlorophyll

Describe and explain how the structure of the small intestine is adapted for absorbing digested food

1. long;

2. villi / villus / microvilli;

3. increase surface area / eq;

4. diffusion / active transport / osmosis;

5. capillaries;

6. (blood flow) maintains concentration gradient /

maintains diffusion gradient;

7. thin walls / one cell thick / short distance;

(applies to villi or capillaries)

8. lacteal(s);

Suggest the consequences of having a diet that contains too much fat

Obesity

Blockage of arteries

High blood pressure

Diabetes

Joint damage / arthritis

Gall stones

Suggest the consequences of having a diet that lacks fresh fruit and fibre

lack vitamin C / antioxidant / scurvy /

bleeding gums / eq;

2. constipation / less food movement /

bowel cancer / raised cholesterol /

increase heart disease / eq;

What is meant by the term transpiration

Evaporation of water

At surface of plant

Describe how the structure of a leaf is adapted to absorb carbon dioxide

Large surface area

Thin

Moist

Spongy mesophyll

Stomata

Describe how the bottles can be sterilised

Steam / radiation / high temperature / disinfectant / ethanol / washed in hot water

Explain why breathing rate is higher after exercise

Oxygen is required

For respiration

To provide energy to muscles

And to remove lactic acid

An oxygen debt builds up

And carbon dioxide needs to be removed

Describe how smoking damages the lungs

1. bronchitis;

2. cilia(ted cells) anaesthetised / damaged / eq;

3. bacteria / pathogens / microorganisms;

4. cancer / carcinogens / tumour;

5. tar;

6. emphysema;

7. less surface area / less gas exchange / less diffusion / eq;

8. idea that alveoli digested / damaged / fused /

Suggest how carbon monoxide will increase the risk of producing a smaller baby

1. red blood cells;

2. (oxy)haemoglobin / carboxyhaemoglobin;

3. less oxygen;

4. (less) respiration / metabolism / energy / ATP;

Describe how the structure of a fish differs from that of a human heart

Fewer chambers

Fewer valves

No septum

Chamber walls have similar size

Fewer blood vessels

Explain the differences in the concentrations of gases (fish heart and human heart leaving aorta)

1. less oxygen/deoxygenated in fish heart;

2. more carbon dioxide in fish heart;

3. oxygen used in respiration;

4. carbon dioxide produced by respiration;;

5. blood oxygenated in human lungs;

6. carbon dioxide removed in human lungs;

Explain why the pressure of the blood returning to the fish heart is lower than the pressure of blood returning to the human heart

1. single circulation /

no separate lung circulation /

blood passes through heart once /

blood in fish has to pass through two sets of

capillaries / eq;

2. fish are smaller / fish have smaller heart /

fish heart has thinner walls;

Explain how having more red blood cells is an advantage to athletes who take part in long distance races

more oxygen;

haemoglobin;

muscles;

respiration;

(less) anaerobic respiration;

(less) lactic acid / (less) oxygen debt /(less)

fatigue / (less) cramp;

more energy;

run faster / run longer / run further / less tired /

eq;