Exam 37: A: Genetics and Heredity

The scientific study of inheritance is called genetics.

A person with heterozygous sex chromosomes is a female.

Disease genes never provide biological advantages for human populations,regardless of the circumstances.

One form of gene therapy uses bacteria-like DNA plasmids to carry therapeutic genes to a cell.

Nondisjunction results in gametes that produce trisomy but not monosomy in the cells of offspring.

Chorionic villus sampling is a newer procedure than amniocentesis.

Many of the polypeptides formed by encoded genes are enzymes that control and regulate chemical reactions in the cell.

A mutation caused by the loss of nucleotide bases in DNA sequence is called a deletion mutation.

A strand of DNA wound around a histone is called a nucleosome.

Osteogenesis imperfecta is a dominant genetic disorder of connective tissue.

Genes are segments of DNA molecules.

One specific transcribed mRNA strand will always produce the same polypeptide.

An ideogram and a pedigree show almost the same information.

Pseudogenes are gene fragments that can be reassembled to form a variety of polypeptides.

The human genome contains about 200,000 genes.

Cystic fibrosis commonly occurs among all ethnic groups.

Crossing over increases genetic variation by forming new linkage patterns.

For an individual to have Down syndrome,one of the gametes had to have contained 24 chromosomes.

Gregor Mendel proved that "independent units" are responsible for the inheritance of biological traits.

The chromosome with the fewest number of genes is carried by about only half the population.