Reproduction And Inheritance

Question 1

What is asexual reproduction?

Answer 1

Reproduction involving only one parent, producing genetically identical offspring (clones).

Question 2

What is sexual reproduction?

Answer 2

Reproduction involving the fusion of male and female gametes, producing genetically varied offspring.

Question 3

What are gametes?

Answer 3

Sex cells – sperm and egg in animals, pollen and egg in plants.

Question 4

Give two advantages of asexual reproduction.

Answer 4

Fast reproduction, no need for a mate.

Question 5

Give two disadvantages of asexual reproduction.

Answer 5

No genetic variation, vulnerable to disease.

Question 6

Give two advantages of sexual reproduction.

Answer 6

Genetic variation, species can adapt over time.

Question 7

Give two disadvantages of sexual reproduction.

Answer 7

Slower, needs two parents.

Question 8

What is pollination?

Answer 8

The transfer of pollen from the anther to the stigma.

Question 9

What are the two types of pollination?

Answer 9

Insect pollination and wind pollination.

Question 10

Name two features of insect-pollinated flowers.

Answer 10

Bright petals, sticky stigma, scented.

Question 11

Name two features of wind-pollinated flowers.

Answer 11

Small dull petals, long stamens, feathery stigma.

Question 12

What happens after pollination?

Answer 12

Fertilisation – the pollen nucleus joins with the ovule nucleus.

Question 13

What is a seed made from?

Answer 13

Fertilised ovule.

Question 14

What conditions are needed for germination?

Answer 14

Water, oxygen, warmth.

Question 15

What are the functions of cotyledons in a seed?

Answer 15

Store food for the growing embryo.

Question 16

Where are sperm produced?

Answer 16

In the testes.

Question 17

Where are eggs produced?

Answer 17

In the ovaries.

Question 18

What is the function of the uterus?

Answer 18

Where the embryo implants and develops.

Question 19

What is the function of the placenta?

Answer 19

Allows exchange of nutrients, oxygen, and waste between mother and baby.

Question 20

What is the function of the umbilical cord?

Answer 20

Connects the fetus to the placenta.

Question 21

What is the function of amniotic fluid?

Answer 21

Protects the baby by cushioning it.

Question 22

What is the menstrual cycle?

Answer 22

A 28-day cycle that prepares the uterus for pregnancy.

Question 23

What hormone causes the egg to be released (ovulation)?

Answer 23

Luteinising Hormone (LH)

Question 24

What hormone maintains the uterus lining?

Answer 24

Progesterone

Question 25

What hormone causes the uterus lining to grow?

Answer 25

Oestrogen

Question 26

What is a chromosome?

Answer 26

A long molecule of DNA found in the nucleus; contains many genes.

Question 27

What is a gene?

Answer 27

A section of DNA that codes for a protein.

Question 28

What is an allele?

Answer 28

A different version of a gene.

Question 29

What does dominant mean?

Answer 29

An allele that is always expressed if present (only needs one copy).

Question 30

What does recessive mean?

Answer 30

An allele that is only expressed when two copies are present.

Question 31

What is genotype?

Answer 31

The genetic makeup (e.g., Bb or bb).

Question 32

What is phenotype?

Answer 32

The physical appearance or trait (e.g., brown eyes).

Question 33

What does homozygous mean?

Answer 33

Having two identical alleles (e.g., BB or bb).

Question 34

What does heterozygous mean?

Answer 34

Having two different alleles (e.g., Bb).

Question 35

How many chromosomes are in a human body cell?

Answer 35

46 chromosomes (23 pairs).

Question 36

How many chromosomes are in a human gamete?

Answer 36

23 chromosomes (haploid).

Question 37

What is a Punnett square used for?

Answer 37

To predict genetic outcomes of crosses.

Question 38

What is a genetic diagram?

Answer 38

A diagram showing how alleles are inherited.

Question 39

What is meant by 'monohybrid inheritance'?

Answer 39

Inheritance of a single gene.

Question 40

What are sex chromosomes?

Answer 40

Chromosomes that determine sex – XX for female, XY for male.

Question 41

What is meant by variation?

Answer 41

Differences between individuals of the same species.

Question 42

What is continuous variation?

Answer 42

Variation with a range (e.g., height), affected by genes and environment.

Question 43

What is discontinuous variation?

Answer 43

Variation with distinct categories (e.g., blood group), controlled by genes.

Question 44

What is mutation?

Answer 44

A change in the DNA sequence of a gene.

Question 45

What can increase the mutation rate?

Answer 45

Ionising radiation and some chemicals (mutagens).

Question 46

What is natural selection?

Answer 46

Organisms with beneficial traits survive and pass them on.

Question 47

What is selective breeding?

Answer 47

Humans choosing parents with desired traits to breed offspring with those traits.