Repeats

Question 1

The diagram shows the unspecialised cells of a mammalian embryo soon after fertilisation.

What is the correct description of these cells?

Answer 1

stem cells undergoing mitosis

Question 2

Restriction enzymes purpose

Answer 2

Red Dog. Cut DNA.

Question 3

What is the fovea and its contents?

Answer 3

It is the part of the retina where cone cells are very tightly packed; this is where light is focused when you look directly at an object. Rods are found further out on the retina and are less tightly packed, showing us a less detailed image.

Question 4

Which statements describe how an oxygen debt is removed after vigorous exercise?

1 Lactic acid is transported to the liver.
2 Lactic acid is respired aerobically.
3 Heart rate stays high to remove lactic acid from the muscles.

Answer 4

All 3.

Question 5

Cross-pollinated vs Self-pollinated

Answer 5

Cross: same species, different plant
Self: same plant, same or different flower

Question 6

What happens to the mass of DNA in a nucleus before mitosis occurs?

Answer 6

Doubles.

Question 7

Decomposition

Answer 7

The plant protein, containing nitrogen, is broken down to ammonium ions which are then released into the soil.

Question 8

Plants use nitrate ions to make plant proteins. This process is called?

Answer 8

Absorption

Question 9

Cellulose can be broken down to..

Answer 9

Glucose.

Question 10

That weird chloroplast oxygen bacteria question.

Answer 10

Photosynthesis

Question 11

The villus. Which vessel transports to the liver?

Answer 11

The vein, on the right.

Question 12

What do the structures in villi absorb?

Answer 12

Blood capillary: glucose and amino acids
Lacteal: fatty acids and glycerol

Question 13

Which statement about the synthesis of a protein molecule in a cell is correct?

Answer 13

The sequence of amino acids is determined by the sequence of bases in the mRNA.

Question 14

In humans, what is the genotype of a red-green colour-blind male?

Answer 14

X^rY

Question 16

Scientists discover a new species of animal.
It has a segmented body with two pairs of legs on each segment.
To which group of animals does this new species belong?

Answer 16

Myriapods

Question 17

Which process is involved in the uptake of glucose by the epithelial cells of kidney tubules?

Answer 17

active transport

Question 18

Starch is digested by amylase in the mouth, but it is not digested in the stomach.
What is the reason for this?

Answer 18

The pH in the stomach is not suitable for the amylase to work.

Question 19

A plant with striped leaves was kept in bright light for six hours.

white stripe

green stripe

A leaf was taken from the plant and the chlorophyll was removed. The leaf was then tested for
starch using iodine solution.
Which diagram shows the result of the test?

Answer 19

yellow-brown for white stripe and blue-black for green stripe

Question 20

Water diffuses into the root hair cell. Water travels by osmosis through the..

Answer 20

cortex. Some water seeps in between or through cell walls, not always entering the cell. Water reaches the xylem in the middle of the root.

Question 21

Which statements about auxin are correct?
1 Auxin is made in all cells in plants.
2 Auxin causes cells to elongate.
3 Auxin moves between the cells by osmosis.
4 Auxin is unequally distributed.

Answer 21

2 and 4

Question 22

A zygote has ten chromosomes in its nucleus.
Which row shows the number of chromosomes in the cells of this species?
1.Body cells, sperm cells, embryo cells.

Answer 22

1. 10
2. 5
3. 10

Question 23

How will the composition of a pregnant woman’s blood change as it passes through the placenta?

Answer 23

Oxygen decreases. Urea increases.

Question 24

One type of contraceptive pill contains progesterone and oestrogen. Some effects of the pill are
listed.
1 inhibit FSH production
2 inhibit LH production
3 inhibit thickening of the uterus wall
Which prevent the development and the release of an egg cell?

Answer 24

all 3

Question 25

The diagram shows a section of a flower that has been cross-pollinated. Which statements about this flower are correct? 1 The pollen produced by this flower will be genetically different from the pollen on the stigma. 2 The pollen was carried to the stigma by wind. 3 This flower is insect-pollinated because the stigma is enclosed by the petals. 4 The pollen was produced by another flower on the same plant.

Answer 25

1 and 3

Question 26

What is the onion bulb acting as in stage 3 and in stage 6? 3 -> leaves long, bulb small 6 -> leaves short, bulb big

Answer 26

sink source

Question 27

How are the leaves on a dicotyledon?

Answer 27

broad leaves

Question 28

If vasodilation occurs at X, what happens to the blood flow at Y and Z?

Answer 28

increases

Question 29

What are the 4 phases? Explain whether the reproduction rate is higher than the death rate at each phase.

Answer 29

lag- yes exponential- yes stationary- no death- no

Question 30

The graph shows how the turgor pressure inside a plant cell varies when the cell is placed in external solutions of different concentrations. Graph is showing 'deceleration'. What is the state of the cell at point X, the end part?

Answer 30

It has lost water and is flaccid.

Question 31

The valves in the heart.

Answer 31

Between the atrium and ventricle: (atrioventricular valves) bicuspid and tricuspid (right) semi-lunar: ones at the top, prevent backflow

Question 32

The valves in the heart.

Answer 32

Between the atrium and ventricle: (atrioventricular valves) bicuspid and tricuspid (right) semi-lunar: ones at the top, prevent backflow

Question 33

Which substances are excreted from the human body? 1 carbon dioxide 2 urea 3 water

Answer 33

All 3

Question 34

Suggested actions for reducing bacterial resistance.

Answer 34

Only use antibiotics when necessary. Do not use antibiotics to treat viral infections.

Question 35

A disease cannot be treated with antibiotics. What could be the reasons for this? 1 It is not a bacterial disease. 2 The pathogen is a virus. 3 The patient has become resistant to the antibiotic.

Answer 35

1 and 2 only

Question 36

In a mesophyll cell, where are chloroplasts found?

Answer 36

cytoplasm

Question 37

The concentration of nitrate ions is higher inside a root hair cell than in the soil. What would be required for the absorption of nitrate ions into the root hair cell? 1 mitochondria 2 oxygen 3 membrane proteins 4 cell wall

Answer 37

1,2,3

Question 38

Which part absorbs the most water in the digestive system?

Answer 38

small intestine

Question 39

Three statements about anaerobic respiration are listed. 1 In humans, the product is lactic acid. 2 In yeast, the product is lactic acid. 3 It releases more energy per glucose molecule than aerobic respiration. Which statements are correct?

Answer 39

1 only

Question 40

What is the balanced chemical equation for a type of respiration that occurs in yeast?

Answer 40

C6H12O6 = 2C2H5OH + 2CO2

Question 41

The 3 neurones.

Answer 41

sensory= very long and skinny relay= looks like an eyeball motor= the regular one

Question 42

Some statements about mutations are given. 1 A random change in the amino acid sequence in DNA causes gene mutation. 2 A mutation is a genetic change. 3 Ionising radiation decreases the rate of mutation. 4 New alleles are formed by mutations. Which statements are correct?

Answer 42

random change in sequence of bases in dna ionising radiation increases the rate of mutations 2 and 4

Question 43

Some ways in which humans make use of organisms are listed. 1 using yeast to produce ethanol 2 artificial selection of sheep with thick wool 3 using bacteria to produce human substances What are examples of genetic modification?

Answer 43

3 only