N4 Unit 2 Part B

Question 1

What is variation?

Answer 1

The differences between members of the same species

Question 2

What is discrete variation?

Answer 2

Variation which falls into distinct groups e.g. blood type.

Question 3

What is continuous variation?

Answer 3

Variation which has a range of values e.g. height.

Question 4

In which cell structure is the genetic information found?

Answer 4

Nucleus

Question 5

What percentage of their DNA does a child inherit from each parent?

Answer 5

50%

Question 6

What does polygenic mean?

Answer 6

A trait which is controlled by many genes

Question 7

What name is given to the different forms of a gene?

Answer 7

Allele

Question 8

How many copies of every gene does a diploid organism have?

Question 9

Define the term recessive.

Answer 9

Recessive alleles only show up in the appearance of an organism if they are paired with another recessive allele.

Question 10

Define the term dominant.

Answer 10

Dominant alleles always show up in the appearance of the organism even if there is only one copy present in the gene pair.

Question 11

Define the term phenotype.

Answer 11

Phenotype describes the appearance of an organism.

Question 12

Define the term genotype.

Answer 12

The genotype of an organism tells us which forms of each gene (alleles) are present.

Question 13

What is germination?

Answer 13

The process whereby a seed starts to grow.

Question 14

What factors are required for germination?

Answer 14

Water, oxygen and a suitable temperature.

Question 15

What is an annual plant?

Answer 15

Annual plants go through their whole life cycle in a single year.

Question 16

What is a perennial plant?

Answer 16

Perennial plants do not die but grow again next year.

Question 17

What are mammals?

Answer 17

Animals which are warm-blooded with a backbone and produce milk to feed its young.

Question 18

What factors do humans need to grow and develop properly?

Answer 18

Water, a balanced diet, vitamins and minerals

Question 19

What is homeostasis?

Answer 19

Keeping conditions in the body at a constant level.

Question 20

Why is it important to maintain a stable body temperature?

Answer 20

To ensure the chemical reactions in the body can take place at the right speed.

Question 21

Name two conditions in the body which need to be kept constant.

Answer 21

Blood glucose concentration and temperature

Question 22

Which organ detects changes in body temperature?

Answer 22

Brain

Question 23

Which organ acts as the effector to maintain your temperature?

Answer 23

Skin

Question 24

What is vasodilation?

Answer 24

The arterioles at the surface of the skin dilate to allow heat to be lost by radiation.

Question 25

Give body responses to an increase in temperature?

Answer 25

Vasodilation, increased sweating and hairs lie flat.

Question 26

What is vasoconstriction?

Answer 26

The arterioles at the surface of the skin constrict to reduce heat loss by radiation.

Question 27

Give body responses to a decrease in temperature?

Answer 27

Vasoconstriction, shivering and hairs stand on end.

Question 28

How does sweating aid heat loss?

Answer 28

As the sweat evaporates heat is lost from the body.

Question 29

How is glucose stored in the body?

Answer 29

As glycogen

Question 30

Where is glycogen stored?

Answer 30

In the liver

Question 31

Which organ releases insulin and glucagon?

Answer 31

Pancreas

Question 32

Which hormone is released when blood glucose concentration increases?

Answer 32

Insulin

Question 33

What is the role of insulin?

Answer 33

Causes the liver to turn glucose into glycogen

Question 34

Which hormone is released when blood glucose concentration decreases?

Answer 34

Glucagon

Question 35

Which is the role of glucagon?

Answer 35

Causes the liver to turn glycogen into glucose