MOD E

Question 1

What does a gene do

Answer 1

Directs the synthesis of a specific protein which can play structural or functional role in the cell

Question 2

Define allele

Answer 2

Different versions of a gene— alleles produce different versions of traits determined

Question 3

How many alleles in somatic cells

Answer 3

2– 1 on each homologous chromosome

Question 4

Homo vs heterozygous

Answer 4

Homo; Individs with 2 copies of the same allele
Hetero; Individuals wit diff alleles of a given gene

Question 5

Genotype vs phenotype

Answer 5

Gene- precise set of alleles a person has for given trait(s)— whether person is homo/heterozygous

pheno-observable trait(s) of individs

Question 6

Define concept of dominant vs recessive traits

Answer 6

Dòm; expressed when an individual has at least one dominant allele
Rec; expressed when individual has two copies of recessive allele

Question 7

FF , Ff, ff

Answer 7

Homo dom , hetero , homo recess

Question 8

Define autosomal linkage and sex linkage

Answer 8

Auto; genes inherited together, located on the same nonsex chromosome (autosome)
Sex; genes inherited differently in males and females located on the sex chromosomes

Question 9

Explain the concept behind codominant and incomplete dominance

Answer 9

Co; both alleles expressed equally in hetero condition
Incomplete; no allele dominant over the other, blended phenotype

Question 10

Explain how the environment can affect an individuals phenotype

Answer 10

Nutrition, temperature exposure
Examples are diet and disease, influencing adult height, and exposure to sunlight influencing skin colour

Question 11

Explain the concept of genetic testing and how it may be used

Answer 11

-detect genetic disorders, disease related alleles
-find faulty genes for family planning
-test for recessive alleles eg) cystic fibrosis

Question 12

Explain prenatal genetic testing; amniocentesis & chorionic villi sampling

Answer 12

-recommended for family w history of defective genes

• amnio; withdraw amniotic fluid, examine cells for abnormalities in chromosome numbers, presence of a certain alleles that cause specific diseases
  -chor; removing and analyzing tissue from chorion
  

Question 13

Newborn genetic testing

Answer 13

-a blood test discrete newborns for phenylketonuria- metabolic disorder
-Too much phenylalanine, too little tyrosine = imbalance
-Strict diet to prevent brain damage

Question 14

What is a human pedigree?

Answer 14

A family tree written in a way that genes of the family can be easily followed