Exam 3: Seciton 3: Beginnings: Heredity and Environment

Harold and Heather are twins. They are the result of _____.

Justin and Jacob are identical twins. They are the result of _____.

Allen learned in his college biology class that, with respect to the sex chromosomes, the _____.

Brown-eyed Alma has a blue-eyed mother and a brown-eyed father. In this case, her brown eyes were determined by a _____ allele.

An individual's phenotype is dependent on _____.

The statistic that indicates how much of the variation in a particular trait can be traced to genes is called _____.

An individual's genetic inheritance is called a(n) _____.

The interaction of a heterozygous pair of alleles in such a way that the phenotype reflects one allele more than the other is referred to as a(n) _____.

_____ are more likely to be carriers of X-linked traits, and _____ are more likely to express them.

Fraternal twins are also called _____ twins.

_____ is when genes have different effects depending on whether they come from the mother or the father.

Individuals who may especially benefit from preconception, prenatal, or even prenuptial (before marriage) genetic counseling include all of the following EXCEPT _____.

A small section of a chromosome that is the basic unit for the transmission of heredity is a _____.

A high school science teacher asks the students what cells could be used to produce any other cell in the body. If the students respond with _____ cells they will be correct.

Dizygotic twins have _____ of their genes in common.

On the 23rd pair of chromosomes, males have _____.

After twins are conceived, their chance of survival until birth depends on the prenatal circumstances. An early sonogram might reveal two developing organisms, but later only one embryo continues to grow. This is referred to as the _____ twin phenomenon.

The instructions for making amino acids are on about 3 billion pairs of chemicals called _____.

Lacy has a recessive gene in her genotype that is not expressed in her phenotype. She is a(n) _____ of that gene.

Ways in which chromosomal and genetic problems are relevant to human development include all of the following EXCEPT _____.