Genes

Question 1

Gene

Answer 1

• 1 set from each parent
• a segment of DNA that codes for a specific protein
• the order of the pattern codes for a specific trait, eg toung rolling

Question 2

Human karyotype

Answer 2

• all of the chromosomes matched to their pair is a karyotype
• 3 features are used to identify pairs, length of chromosome, pattern of dark bands on chromosome, and position of centromere connection
• the last two chromosomes are sex chromosomes
• 23 chromosomes form male is matched with 23 chromosomes from female
• paired chromosomes are homologous, which means same information ( eye colour)
• similar shape, size, and gene arrangement

Question 3

Amniocentesis

Answer 3

A prenatal test done to look at the karyotype of an unborn child

Question 4

Mitosis

Answer 4

• body cells divide by replicating all type parts and dividing into 2 identical cells
• parent cell is the original cell
• daughter cell is the two new identical cells
• both parent and daughter are diploid cells
• each cell has 2 copies of each chromosome
• represented as 2n where 2 is 2 copies and n is the number of unique chromosome types
• plants undergo mitosis

Question 5

Asexual reproduction

Answer 5

The production of genetically identical offspring from one individual

Question 6

Meiosis

Answer 6

• two stage form of cell division
• reproductive cells (gametes) are used to reproduce sexually with only half the number of chromosomes as the original cell
• in humans, sperm is the male and egg for female
• homologous chromosomes pair up and exchange segments of DNA which result in slight genetic differences
• parent cell is diploid 2n
• daughter cell is haploid 1n

Question 7

Crossing over

Answer 7

Creates completely new combinations of traits in next generation

Question 8

Fertilization

Answer 8

The sperm and the egg are each haploid, the fertilized egg is diploid and can reproduce through mitosis
- crossing over improves the variation possible in the gametes, explains why siblings look so different

Question 9

Selective breeding

Answer 9

• used to improve domestic varieties of planters and animals (choosing individuals with useful characteristics to produce a more desirable plant or animal stock