B2- Inheritance, Variation, Evolution

Question 1

Define sexual reproduction

Answer 1

The formation of a new organism by combining the genetic material of two organisms.

Question 2

What are sexually produced offspring like?

Answer 2

Genetically similar to both parents but not identical to either

Question 3

Define fertilization

Answer 3

The joining of two sex cells (egg and sperm) or the male and female gametes

Question 4

Which gametes are in animals and flowering plants?

Answer 4

Sperm and egg in animals
Pollen and eggs in flowering plants

Question 5

4 advantages of sexual reproduction

Answer 5

• Variation in offspring
• Can adapt to new environments
• Disease is less likely to effect all individuals in population
• Can use selective breeding

Question 6

3 disadvantages of sexual reproduction

Answer 6

• Time and energy are needed to find a mate
• Impossible for an isolated individual
• Takes longer than asexual

Question 7

Define asexual reproduction

Answer 7

Only involves one parent so there is no joining of sex cells during fertilisation

Question 8

What are asexually produced offspring like?

Answer 8

Genetically identical to each other and their parent often called clones

Question 9

Examples of asexual organisms

Answer 9

Bacteria
Production of fungi spores
Plant runners
Plant tubers

Question 10

4 advantages of asexual reproduction

Answer 10

• Rapid population increase in favourable conditions
• Only one parent is needed
• Time and energy efficient as a mate is not needed
• Faster than sexual

Question 11

3 disadvantages of asexual reproduction

Answer 11

• No variation in population
• Species may only be suited to one habitat
• Disease may affect all individuals in a population

Question 12

List 3 organisms that reproduce both sexually and asexually

Answer 12

Malarial parasites
Fungi
Some plants

Question 13

Malarial asexual and sexual reproduction facts

Answer 13

• Malarial parasites reproduce sexually in the host mosquito
• Malarial parasites reproduce asexually in the human host

Question 14

Fungi asexual and sexual reproduction facts

Answer 14

• Fungi reproduce sexually to generate variation
• Fungi release spores by asexual reproduction

Question 15

Plants asexual and sexual reproduction facts

Answer 15

• Plants use sexual reproduction to produce seeds
• Plants such as strawberries reproduce asexually by sending out runners, or daffodils when their bulbs divide

Question 16

How do plants sexually reproduce?

Question 17

Describe the process of meiosis

Answer 17

Answer in book

Question 18

Describe the process of mitosis

Answer 18

Answer in book

Question 19

Define DNA

Answer 19

Deoxyribonucleic acid.
The material inside the nucleus of cells, carrying the genetic information or code of a living being.

Question 20

Describe the structure of DNA

Answer 20

A polymer, a large and complex molecule. It is made up of two strands called nucleotides forming a twisted ladder structure called a double helix. The nucleotides consist of a deoxyribose sugar, phosphate and base.

Question 21

Nucleus

Answer 21

Contains cell DNA or genetic material

Question 22

Chromosome

Answer 22

23 Pairs
Made up of DNA
Contains thousands of genes

Question 23

Gamete

Answer 23

Sex cell

Question 24

Gene

Answer 24

Codes for proteins section of DNA

Question 25

Allele

Answer 25

Differently forms of a gene eg brown hair allele

Question 26

Phenotype

Answer 26

Describing a characteristic eg brown eyes

Question 27

Genotype

Answer 27

What alleles are present eg BB or Bb

Question 28

Homozygous

Answer 28

2 copies of the same allele

Question 29

Heterozygous

Answer 29

2 different alleles

Question 30

Dominant

Answer 30

Needs one copy of the allele for the characteristic to be seen

Question 31

Recessive

Answer 31

Only see characteristic if there are 2 allele copies

Question 32

Human genome

Answer 32

Do later

Question 33

What is a gene mutation?

Answer 33

Do later

Question 34

List the 3 main symptoms of Cystic Fibrosis

Answer 34

- Difficulty breathing - Difficulty digesting -Difficulty reproducing

Question 35

List the 1 symptom of Polydactyly

Answer 35

Born with one or more extra fingers

Question 36

Are CF and Poly recessive or dominant

Answer 36

CF= Recessive Poly= Dominant

Question 37

How do you screen for genetic diseases?

Question 38

What problems surround screening for genetic diseases?

Question 39

How can we genetically modify organisms?

Question 40

Human genome