BIOLOGY - UNIT 5: GENETICS: GOD'S PLAN OF INHERITANCE QUIZ 1-4

Biochemists have found that though the amount of any given base found in DNA varies considerably from one species to another, the amount of adenine is always equal to the amount of:

thymine

A TT genotype is said to be _________.

homozygous

When the alleles of a gene pair are identical they are said to be:

homozygous

The complete genetic code of an organism is present:

in the nucleus of all somatic cells

What is meant by homologous chromosomes?

the gene's alleles are found in matched chromosome pairs

As a result of nondisjunction, a female gamete may contain:

two sex chromosomes, no sex chromosomes

The Talmud permitted a father with hemophilia to have his son circumcised. Would this preclude all possible problems?

yes-if the mother did not carry the trait (heterozygous)

In the cross BB x bb the percent of offspring in the F1 generation that will have the same genotype as their parents is:

0%

If the parent genotypes are Aa and Aa, the offspring are expected to be:

1/4 AA, 1/2 Aa, 1/4 aa

The second generation phenotypes resulting from the cross of true-breeding monohybrid pollination will display a ratio of:

1:3

If an organism has 6 haploid chromosomes, how many chromosomes are present?

6

Genes are composed of:

DNA

In considering this cross (YyRr and YyRr), the genotype ratio is: YYRR; 2YYRr; 2Yyrr; 4YyRr; YYrr; 2Yyrr; yyRR; yyRr; yyrr.

False

A person whose blood tests show neither protein A nor protein B present has blood type:

O

Which of these paired genes is homozygous?

PP and pp

All ova contain sex chromosomes corresponding to:

X

The human chromosome apparently lacking in gene influence is the:

Y chromosome

Suppose you have monohybrid pea plants in your garden and find that they produce round seed to wrinkled seeds in the ratio of 3:1. If the allele are designated (R & r) receptively. What is the probable Phenotype of the parents (P1)?

all round

Different forms of a given gene are known as:

alleles

Radiation damage has hereditary effects if it:

alters the DNA in gametes

A person with Klinefelter's syndrome possesses:

an extra X chromosome

The Y chromosome in human males:

appears to be genetically almost inactive

Within a set of human chromosomes, 22 pairs are called:

autosomes

Why didn't Charles Edward, the grandson of Queen Victoria, receive hemophilia from his father Leopold?

because the disease is not on the "Y" chromosome and Helena did not have the trait

"Linkage" refers to genes for different traits

being located on the same chromosome

Mutations can be caused by:

both

A pedigree chart can show a trait that is:

both dominant and a mutation

Differences among blood groups result from:

chemical differences on the red blood cell

Down's syndrome involves a:

chromosomal abnormality

Fertilization produces in the offspring:

double the haploid number of chromosomes

Genes that carry contrasting inheritance factors are called:

heterozygotes

An organism possesses one copy of each allele type for a given gene. It is said to be...

heterozygous for the gene

In a dihybrid cross, the F2 will have nine genotypes, but only four phenotypes because the ___________ genes cause __________ the traits to mask the __________ traits.

heterozygous, dominant, recessive

A (TT) genotype is said to be:

homozygous

Some scientists believe that sickle-cell anemia is a beneficial mutation because it:

increases resistance to malaria

Sex cells are produced in a process called .

meiosis

In the Watson-Crick model of a double helix, the "steps" of the "spiral staircase" are composed of:

nitrogen bases

A family has seven sons. The chance that their eighth child will be a daughter is:

one chance in two

If a woman heterozygous for color-blindness marries a normal man:

one-half of the sons are expected to show color blindness

Which problems are associated with sickle-cell anemia?

oxygen respiration, blood circulation

The ratio of the offspring of 9:3:3:1 is for the:

phenotype

Suppose you have monohybrid pea plants in your garden and find that they produce round seed to wrinkled seeds in the ratio of 3:1. The allele are designated (R & r) receptively.

rr only

Genes act by directing the formation of:

specific enzymes

How can a mutation be inherited?

through gamete reproduction and fertilization, through meiosis and fertilization