Biology 3E

1.

1 point

The cell sap of a root hair cell has a higher concentration of nitrates than the surrounding soil. Which feature of the cell stops these nitrates moving back from teh cell to the soil?

cell membrane

cell wall

large surface area

water potential gradiet

2.

1 point

Which conditions cause the fastest rate of transpiration?

dry and cold

dry and warm

wet and cold

wet and warm

3.

1 point

In the small intestine, a is the main function of the villi?

to cause food to be swept along more swiftly

to cause more efficient absorption of digested food

to remove water from undigested food

to secrete enzymes

4.

1 point

Which of the following is correct about the substrate and enyme?

substrate - lock and enzyme - key

substrate - key and enzyme - lock

substrate - product and enzyme - key

substrate - lock and enzyme - product

5.

1 point

The coronary arteries carry blood to the ___

brain tissue

heart muscles

liver cells

walls of alveolus

6.

1 point

An experiment was performed on a young plant using an aphid stylet to measure the rate of transport in the phloem. The same pant was then placed in a bell jar and a chemical placed in the bell jar to absrob all the oxygen present. The rate of transport in the phloem decreased and then stopped.
What is the reason for this?

companion cellsno longer produce suffient energy

mitochondrion in the xylem vessels cease to function

photosynthesis cannot occur inthe bell jar

translocation occurs only by diffusion

7.

1 point

What is the purpose of deamination?

to oxidise proteins for energy

to produce urea

to remove excess amino acids

to make new amino acids

8.

1 point

A person's diet contains more protein than is needed for growth and repair. This causes increased production of ...

carbon dioxide

hormnes

sweat

urea

9.

1 point

How is carbon monoxide in tobacco smoke harmful?

it causes emphysema

it causes lung cancer

it combines with haemoglobin

it kills the cells lining the trachea

10.

1 point

Which of the following cells can photosynthesizes?

upper epidermal cells

lower epirdermal cells

stomata

guard cells

11.

1 point

Which of the following subsances in cigarettes causes blood to clot easily?

carbon monoxide

nicotine

smoke

tar

12.

1 point

Which property of water is essental for blood to be pumped by the human heart?

it has high specific heat capacity

it is an excellent solvent

it is most dense at +4oC

it is inompressible.

13.

1 point

What cases the symptom of bronchitis?

breakdown of alveolar walls

inflamation of airway walls

narrowing of pulmonary ateries

uncontrolled division of lung cells

14.

1 point

The statements are about how liver deals with excess glucose.
1. it is converted toamino acids
2. it is converted to fats
3. it is deaminated to produce urea
4. it is stored sgycogen

Which statemens are correct?

1 and 2 only

1,2 and 3

2 and 4

4 only

15.

1 point

A food gives the following results on testing.
- a purple colour in the biuret test
- a blue colour when heated with Benedict's solution
- a yellow colour with iodine
- a white emulsion with ethanol

What nutrient does the food contain?

fat and protein

protein and reducing sugar

reducing sugar and stach

starch and fat

16.

1 point

What is the role of cilia in the gaseous exhange syse?

they increase the surface area for gas exchange

the move air down the trachea

the move mucus up the trachea

they trap dust and bacteria

17.

1 point

Chemicals in tobacco smoke lead to the breakdown of the elastic tissue in the alveoli. What is the name of this condition?

bronchitis

emphysema

heart disease

lung cancer

18.

1 point

Plants use carbon dioxide and water to carry out photosynthesis. Which description is correct?

CO2 and water enter the roots and move through the xylem to each leaf.

CO2 and H2O enter a leaf thrugh stomata and diffue into leaf cells.

COs enters a leaf through stomata and H2O enters a leaf from the xylem

CO2 enters a leaf through stomata an water enters a leaf form the phloem.

19.

1 point

The small intestine contains a low concentration of glucose produced from the digestion of starch. Glucose is taken up by the cells of the villi. How does the glucose move?

by active transport against the conc. gradien

by active transport with the conc. gradient

by diffusion against the conc. gradient

by diffusion with the conc. gradint

20.

1 point

What is an example of active transprt?

movement of ions up the xylem

movement of water into root hairs

uptake of glucose by cells of villi

uptake of oxygen by red blood cell

21.

1 point

Which processes can take place in a root hair cell when oxygen is not available?

active transport only

diffusion only

active transport and osmosis

osmosis and diffusion

22.

1 point

Which blood vessel carries blood with the lowest concentration of urea?

hepatic portal vein

pulmonary vein

renal vein

vena cava

23.

1 point

What does the yeast gain from fermentation?

carbon dioxide for respiration

energy for growth

ethanol for growt

glucose for repiration

24.

1 point

Why does chewing food help digestion?

the food is easier to swallow

the food has a better taste

the food has increased surface area

the food is soter

25.

1 point

Which of the following correctly describes the transpiration process?
1. water evaporates into the air spaces of the leaf
2. water molecules cohere so are pulled upwards in the xylem
3. water passes by osmosi through the stomata
4. water vapour diffuses through the mesophyll cells

3 only

1 and 2

2 and 4

1,3 and 4