Genetics

Question 1

gene

Answer 1

the basic unit of inheritance for a given characteristic

Question 2

allele

Answer 2

one of a number of alternative forms of the same gene responsible for determining contrasting characteristics

Question 3

locus

Answer 3

position of an allele within a DNA molecule

Question 4

homozygous

Answer 4

the diploid condition in which the alleles at a given locus are idientical

aa or AA

Question 5

heterozygous

Answer 5

the diploid condition in which the alleles at a given locus are different

Aa

Question 6

phenotype

Answer 6

the characteristics of an individual usually resulting from the interaction between the genotype and the environment in which development occurs

Question 7

genotype

Answer 7

the genetic constitution of an organism with respect to alleles under consideration

Question 8

dominant

Answer 8

the allele which influences the appearance of the phenotype even in the presence of an alternative allele

A

Question 9

recessive

Answer 9

the allele which influences the appearance of the phenotype ONLY in the presence of another identical allele

a

Question 10

F1 generation

Answer 10

the generation produced by crossing homozygous parental stocks

Question 11

F2 generation

Answer 11

the generation produced by crossing two F1 generations

Question 12

sex-linked genes

Answer 12

genes found on the sex chromosomes, usually on the X chromosome.

women have one more x chromosome than men

Question 13

autosomal genes

Answer 13

genes found on all chromosomes apart from X and Y.

Autosomal means that a specific gene is not on a sex chromosome and is a numbered chromosome. Humans have 46 total chromosomes. Each of your parents gives you 23 chromosomes via the egg or sperm, for a total of 46. There are two sex one pair chromosomes (X and Y) and 22 pairs numbered chromosomes

Question 14

mulitple alleles

Answer 14

there are more than two types of alleles for a particular gene, e.g. blood groups involve three allels A, B, O