Genetics

Question 1

What is DNA?

Answer 1

Deoxyribonucleic acid is the genetic information carried in each cell except for Red Blood Cells.

Question 2

What is the basic Structure of a Nuceleotide

Answer 2

sugar nitrogen molecule joins to a phosphate molecule

Question 3

How nucleotides join together to form DNA

Answer 3

The Nitrogen Base Pair adenine always pairs with thymine and cytosine always pairs with guanine.

Question 4

What complementary base pairs are nucleotides connected by

Answer 4

ATGC

Question 5

Where is a gene in a chromosone

Answer 5

Its has a particular location on the chromosome (called its locus)

Question 6

What is a karotype

Answer 6

A karyotype shows all of these chromosomes paired up and arranged in size for an individual.

Question 7

Differentiate between mitosis and meiosis in terms of process and purpose

Answer 7

Mitosis, a single cell division process, produces two identical daughter cells for growth and repair, while meiosis, a two-step process, generates four genetically unique haploid cells (gametes) for sexual reproduction.

Question 7

diploid

Answer 7

46 chromosomes one from both parents sets (one from each parent) 23 from each parent

Question 8

haploid

Answer 8

one single copy of each chromosome gamete

Question 9

Explain what an allele is and where it is found

Question 9

How non-disjunction occurs and some of the consequences

Answer 9

Nondisjunction, a failure of chromosomes to separate properly during cell division (meiosis or mitosis), leads to daughter cells with an abnormal number of chromosomes (aneuploidy), potentially causing genetic disorders like Down syndrome or Turner syndrome

Question 10

Explain how the two forms of genetic mutation occur and the consequences of these mutations

Answer 10

Substitution mutations replace one base pair with another.
This will only affect one codon, 3 base pairs, and so only causes a slight mutation.

Sickle cell anaemia is an example of this, where the haemoglobin molecule is altered slightly so that it doesn’t carry the oxygen molecule so well.

A frameshift mutation means one of the base pairs is removed and this affects all the codons as all of the other base pairs move along one place on the strand. very big mutation.

Question 11

syndromes

Answer 11

Down syndrome (trisomy 21), Cri-du-chat syndrome (deletion of chromosome 5), and Turner syndrome (missing or altered X chromosome in females.

Question 12

what is a chromatid

Answer 12

A chromatid is one of the two identical halves of a chromosome that has been replicated in preparation for cell division