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Question 1

What is the passage of water through the tissues when it enters a plant?

Answer 1

Root hair —> xylem —> spongy mesophyll

Question 2

What factors have an effect on transpiration

Answer 2

Increase Humidity - decrease
Increase Temperature - increase
Increase Wind Speed - increase

Question 3

In the rate of transpiration, P has a faster rate than Q, give a reason for this

Answer 3

P has a greater number of stomata

Question 4

What cells control the opening and closing of the stomata?

Answer 4

Guard cells

Question 5

Process of water absorption

Answer 5

• Water is absorbed by root hair by osmosis
• Water travels upwards in the xylem
• Water travels to the stomata and evaporates or transpires out

Question 6

What is transpiration

Answer 6

The loss of water by evaporation through the stomata of leaves

Question 7

Explain why the structure and number of villi make absorption an efficient process in the small intestine

Answer 7

Villus has a thin wall, a large surface area, a good blood supply/many capillaries, there a large number of villi which makes absorption faster

Question 8

What is the function of a sperm cell?

Answer 8

Fertilisation - tail to swim

Question 9

What is the function of an egg cell?

Answer 9

Fertilisation - large cell to provide food

Question 10

Describe the feature of stem cells which gives them the potential to develop into many different types of cells

Answer 10

Unspecialised

Question 11

What processes involve stem cells

Answer 11

Repair of broken bones, growth of new skin

Question 12

Name the substance which muscle cells break down to produce pyruvate

Answer 12

Glucose

Question 13

When pyruvate is formed, enough energy is released to form two molecules of a high energy compound, what is the word equation for this?

Answer 13

ADP + Phosphate ——-> ATP

Question 14

What hormone does the pancreas release when blood glucose is low

Answer 14

Glucagon

Question 15

What hormone does the pancreas release when blood glucose is high

Answer 15

Insulin

Question 16

Describe two features of hormones

Answer 16

Made of protein, chemical messengers

Question 17

What is meant by a genotype

Answer 17

The particular alleles that an organism has for a genotype

Question 18

What is meant by a phenotype

Answer 18

The physical appearance expressed by an organism due to their genotype

Question 19

Diploid

Answer 19

Two matching sets of chromosomes (2n)

Question 20

Haploid

Answer 20

One set of chromosomes (n)

Question 21

Discrete

Answer 21

Single gene inheritance of characteristics where measurements fall into distinct groups

Question 22

Continuous

Answer 22

Polygenic inheritance of characteristics where there is a range of values from one extreme to the other

Question 23

Variation

Answer 23

Differences in the characteristics of members of the same species

Question 24

What is meant by polygenic inheritance?

Answer 24

Several genes controlling a characteristic

Question 25

What type of variation is shown by polygenic inheritance

Answer 25

Continuous

Question 26

Look at diagram X in notes and describe how new species are formed

Answer 26

- Initial population is separated - Different mutations occur in each subpopulation - Some mutations are advantageous - Natural selection occurs - Subpopulation groups are no longer able to interbreed

Question 27

Mutation

Answer 27

A random change to genetic material

Question 28

Why is variation important for survival of any population?

Answer 28

Allows population to adapt to changing environmental conditions

Question 29

Name the site of mitosis in plants

Answer 29

Meristem

Question 30

If there are 4 chromosomes present in a cell, how many chromosomes will be present in each of the two cells produced by mitosis

Answer 30

4

Question 31

Describe one difference between passive and active transport

Answer 31

Active transport requires energy, passive transport does not require energy

Question 32

DNA contains genetic material which controls the synthesis of chemicals made from amino acids, name the type of chemicals synthesised

Answer 32

Protein

Question 33

Where is mRNA made

Answer 33

Nucleus

Question 34

Describe the second stage of photosynthesis

Answer 34

Hydrogen and ATP with carbon dioxide produce sugar

Question 35

Two products used in the second stage of photosynthesis

Answer 35

Hydrogen and ATP

Question 36

Name the energy producing process which starts in the cytoplasm and is completed in the mitochondria

Answer 36

Aerobic respiration

Question 37

Why do sperm cells contain more mitochondria than a skin cell

Answer 37

Sperm require more energy as they move

Question 38

Describe how information is passed across a neuron

Answer 38

Electrical impulse

Question 39

Describe the structure and processes involved as water moves through the plant from the soil to the air

Answer 39

- Water moves into the root hairs by osmosis - water travels upwards in the xylem - water travels to the stomata and diffuses out

Question 40

Describe two features of structures which improve efficiency of gas exchange

Answer 40

Large surface area, rich blood supply

Question 41

Mucus and cilia are found in the trachea, describe how the mucus and cilia work together to help prevent bacteria getting into the lungs

Answer 41

Dirt is trapped in the mucus, cilia move these up and away from the lungs