Chapter 4: Modern Genetics Review

An example of a trait that has multiple alleles.

blood types

If a person has the combination of alleles O and B what would their blood type be?

B blood type

Skin color and height are traits that show a large number of different phenotypes because they are controlled by _________.

many genes (polygenic inheritance)

The effects of genes are often changed by an organism’s ____________.

environment

The body cells contain _____ chromosomes.

46

The sex cells contain ___ chromosomes.

23

The two sex chromosomes carried by a male are _____.

XY

The two sex chromosomes carried by a female are ____.

XX

Genes carried on the X or Y chromosomes are called _________.

sex-linked genes

An example of a condition that is sex- linked is ______.

Hemophilia or color-blindness

Sex-linked traits occur more often in ______, because they carry only one X chromosome.

males

A chart that tracks which members of a family have a particular trait is called a ________.

pedigree

In a pedigree chart a square is a symbol for a _____.

male

A half-shaded circle on a pedigree chart would indicate a _________.

carrier female

An abnormal condition that a person inherits through genes or chromosomes is a __________.

genetic disorder

A genetic disorder in which a person’s blood clots very slowly or not at all is called ______.

hemophilia

People with an extra copy of chromosome 21 have a disorder called _________.

Down syndrome

A person who has difficulty distinguishing between the colors red and green has the sex-linked trait called ________.

colorblindness

A picture of all the chromosomes in a cell is called a _________.

karyotype

Professionals who help couples understand their chances of having a child with a particular disorder are called _________

genetic counselors

A procedure in which fluid from a developing baby is removed to test for genetic disorders is called ________.

amniocentesis

A genetic disorder in which the body produces abnormally thick mucus is called __________.

cystic fibrosis

In _______, breeders cross two genetically different individuals.

hybridization

A _____ is an organism that is genetically identical to the organism from which it was produced.

clone

Inserting working copies of a gene directly into cells of a person with a genetic disorder is referred to as _______.

gene therapy

The process of selecting a few organisms with desired traits to serve as parents of the next generation is called _________.

selective breeding

The transfer of genes from one organism to another is called ________.

genetic engineering

The crossing of two individuals that have identical or similar sets of alleles is called _______.

inbreeding