Exam 2: Biological and Environmental Foundations

Baldness is an example of a recessive trait.

Although both of his parents are 5 feet 7 inches tall, 17-year-old Theo is 6 feet tall. He is healthy and has been well nourished since birth. This example illustrates the concept of _____.

_______ is a genetic inheritance pattern in which both genes influence the characteristic.

Today, genetic counseling is recommended for all couples planning to have children.

Maddox and Maecy both carry alleles for brown hair. Their 4-year-old son, Drake, also has brown hair. Therefore, Drake is ______ the trait of brown hair.

Some of the most common chromosomal abnormalities affect the _____ pair of chromosomes.

A(n) ____ is a fertilized egg.

_______ is the most common genetic cause of mental retardation.

Distinguish between the two processes of cell reproduction.

Four-year-old Sam's parents were star athletes in high school and college. They are both coaches and manage a gym during the summer months. Sam has been exposed to sports since he was a baby. In addition to throwing and kicking balls with his parents, Sam recently started soccer and T-ball. He has also been enrolled in swimming lessons since he was 9 months old. Sam is already demonstrating strong athletic skills, despite being very young. This example demonstrates a(n) _____ gene-environment correlation.

A human zygote contains ____ chromosomes from the biological mother and ____ chromosomes from the biological father.

Tonya has straight red hair, blue eyes, and her big toe is longer than her second toe. These characteristics are called _____ traits.

____ are conceived when a woman releases more than one ovum and each is fertilized by a different sperm.

The 23rd pair of chromosomes specify the ______ of the individual.

Approximately 8 percent of African Americans carry the recessive sickle cell trait. However, sickle cell carriers do not develop full-blown sickle cell anemia. In fact, they may function normally but show some symptoms, such as reduced oxygen distribution throughout the body and exhaustion after exercise. This illustrates the ______ genetic inheritance pattern.

Identical twins occur in ____ of every 1,000 U.S. births.

In humans, ___ of the 23 pairs of chromosomes are matched and contain similar genes in almost identical positions and sequence.

______ is a medical specialty that helps prospective parents determine the risk that their children will inherit genetic defects and chromosomal abnormalities.

Trenton, age 50, has Down syndrome. Compared to unaffected adults his age, Trenton is at greater risk for developing ______.

Daughters who inherit the gene for hemophilia: