T3 Lesson 12 - Genetic diagrams

Question 1

phenotype

Answer 1

physical characteristic of an organism

Question 2

genotype

Answer 2

genetic makeup of an organism

Question 3

allele

Answer 3

1 of a number of different forms of a gene.

Question 4

gamete

Answer 4

specialized cell involved in sexual reproduction- containing half the number of chromosomes compared to a body cell

Question 5

gene

Answer 5

sequence of DNA that codes for a protein and thus determines a trait

Question 6

fertilization

Answer 6

process in sexual reproduction in which male and female reproductive cells join to form a new cell

Question 7

genetics

Answer 7

scientific study of heredity

Question 8

dominant allele

Answer 8

the dominant characteristic is always expressed even if only one copy is present.

Question 9

recessive allele

Answer 9

the recessive characteristic is only expressed if two recessive copies are present

Question 10

heterozygous

Answer 10

Aa term used to refer to an organism that has 2 different alleles for the same trait

Question 11

homozygous

Answer 11

AA or aa term used to refer to an organism that has 2 identical alleles for a particular trait

Question 12

punnett square

Answer 12

Diagram showing the gene combinations that might result from a genetic cross

Question 13

sex chromosomes

Answer 13

In human females they are the same (XX) and in males they are different (XY)

Question 14

carriers

Answer 14

parents who have the recessive allele which causes the disorder, but do not have the trait

Question 15

embryo screening

Answer 15

cells from embryos and fetus can be screened for the alleles that cause many genetic disorders