B5

Question 1

What is DNA and where is it found?

Answer 1

DNA (deoxyribonucleic acid) is a molecule that carries genetic information, found in the nucleus of cells.

Question 2

Describe the structure of DNA.

Answer 2

DNA is a double helix made up of two strands with paired bases: adenine (A) with thymine (T), and cytosine (C) with guanine (G).

Question 3

What is a gene?

Answer 3

A gene is a section of DNA that codes for a specific protein or trait.

Question 4

Define genotype and phenotype.

Answer 4

Genotype is the genetic makeup of an organism, while phenotype is the observable traits resulting from the genotype.

Question 5

What is natural selection?

Answer 5

Natural selection is the process where organisms better adapted to their environment tend to survive and reproduce, passing on beneficial traits.

Question 6

What are Alleles?

Answer 6

Different versions of the same gene

Question 7

What is meant by Homozygous and Heterozygous?

Answer 7

Homozygous- Both alleles in the genotype are the same E.g. BB

Heterozygous- The 2 alleles in the genotype are different E.g. Bb

Question 8

What is the difference between:

Dominant alleles

and

Recessive alleles?

Answer 8

Dominant alleles will always be expressed in the phenotype

Recessive alleles are only expressed when there is 2 copies present E.g. bb

Question 9

What chromosomes are:

Males?

And

Females?

Answer 9

Males- XY

Females- XX