genetics and inheritance

Question 1

What is inheritance?

Answer 1

Passing on characteristics from one generation to the next.

Question 2

How are genes transmitted?

Answer 2

From parents’ gametes to offspring.

Question 3

What are the 4 bases in DNA?

Answer 3

Adenine, Thymine, Guanine, Cytosine.

Question 4

Which bases pair together in DNA?

Answer 4

A with T, C with G.

Question 5

What is the structure of DNA?

Answer 5

Two parallel strands twisted to form a double helix.

Question 6

What are the 3 parts of a nucleotide?

Answer 6

Phosphate group, pentose sugar, nitrogenous base.

Question 7

How is RNA different from DNA?

Answer 7

RNA is single stranded; DNA is double stranded.

Question 8

Which base is found in RNA instead of thymine?

Answer 8

Uracil.

Question 9

How many chromosomes do humans have?

Answer 9

46 (23 pairs).

Question 10

What is a karyotype?

Answer 10

Characterization of chromosomes based on size, shape, and number.

Question 11

What is a diploid cell?

Answer 11

A cell with 2 sets of chromosomes (paired).

Question 12

What is a haploid cell?

Answer 12

A gamete cell with one set of chromosomes.

Question 13

What is a gene?

Answer 13

Small section of DNA that codes for proteins.

Question 14

What is an allele?

Answer 14

Alternative form of a gene.

Question 15

Where are proteins made?

Answer 15

Ribosomes in the cytoplasm.

Question 16

What does mRNA do?

Answer 16

Carries a copy of the gene from nucleus to cytoplasm.

Question 17

What determines the protein made?

Answer 17

The sequence of amino acids from mRNA base sequence.

Question 18

What is genotype?

Answer 18

Combination of genes (e.g. GG, Gg, gg).

Question 19

What is phenotype?

Answer 19

Physical traits (e.g. grey or charcoal fur).

Question 20

What does homozygous mean?

Answer 20

Having two identical alleles (GG or gg).

Question 21

What does heterozygous mean?

Answer 21

Having two different alleles (Gg).

Question 22

What is a dominant allele?

Answer 22

An allele that is expressed if present.

Question 23

What is a recessive allele?

Answer 23

An allele only expressed if no dominant allele is present.

Question 24

What is pure breeding?

Answer 24

Both individuals are homozygous for the same allele.

Question 25

What is co-dominance?

Answer 25

Both alleles are expressed in the phenotype.

Question 26

What is an example of co-dominance?

Answer 26

Red + White flower alleles = Pink flowers.

Question 27

What are the blood group alleles?

Answer 27

IA, IB, IO.

Question 28

Which blood group alleles are co-dominant?

Answer 28

IA and IB.

Question 29

Which blood group allele is recessive?

Answer 29

IO.

Question 30

What is a pedigree diagram?

Answer 30

A way of showing genotypes across generations.

Question 31

What shape represents a male in a pedigree?

Answer 31

Square.

Question 32

What shape represents a female in a pedigree?

Answer 32

Circle.

Question 33

What are sex-linked characteristics?

Answer 33

Traits present due to X and Y chromosome differences.

Question 34

Why do sex-linked traits affect males more?

Answer 34

Y chromosome is shorter, missing some genes.

Question 35

What is mitosis?

Answer 35

Nuclear division giving rise to genetically identical cells.

Question 36

Why is mitosis important?

Answer 36

For growth, repair, and asexual reproduction.

Question 37

What is meiosis?

Answer 37

Reduction division forming genetically different haploid cells.

Question 38

What happens in meiosis?

Answer 38

Chromosomes double, divide twice, and crossing over occurs.

Question 39

What are stem cells?

Answer 39

Unspecialised cells that divide to form specialised cells.

Question 40

Where are adult stem cells found?

Answer 40

Bone marrow and brain.