HUMAN GENETICS

Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had homozygous recessive genes? __

10

Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had homozygous genes? 10-30 10 0-10 10-20

10-30

A genetic counselor can also use the principles of population genetics in his advising. What is the basis for this type of counseling?

Answers vary

A pedigree is not helpful to a counselor in predicting the probability of a recessive gene being present and the chances for an offspring to receive the gene and express the trait. True or False

False

population genetics

The study of a hereditary trait in a large population.

Each member of a class sampled a piece of PTC testing paper. Thirty people sampled the chemical. Twenty persons were tasters. How many had heterozygous genes? 0-20 20 indeterminate 10

0-20

gene pool

All of the genes present in a specific population.

A family pedigree is a chart of various patterns that shows a general trend. True or False.

False

gene frequency

How common the gene is in the population.

pedigree

The ancestral history of an individual; a chart showing the history of a trait in the family.

In a large population, approximately 65 percent are tasters and 35 percent are nontasters. Does the class compare favorably to the general population? Yes or No

Yes

The large number of potential gene __________ make it unlikely that any two people will be identical.

combinations

When using data from population genetics research: the sample must be statistically large the sample must be statistically small the sample must be 100% accurate the sample must have a high probability of representing the population

the sample must have a high probability of representing the population

Why do identical twins have the same set of genes? they are born of the same parents they both have haploid chromosomes one or more gametes underwent nondisjunction they were born of one fertilized ovum

they were born of one fertilized ovum