Reproduction/Meiosis and Development Genetics Biotech/ Change over time Cell Cycle DNA

A cell with 8 chromosomes before the beginning of the cell cycle will produce new cells that have

8

A scientist was collecting data about the number of chromosomes that a certain organism had. Most of the skin cells that he examined had a certain amount of chromosomal material, but he found some skin cells with double the chromosomal material. What might be the explanation for these findings?

Some skin cells were in the G2 phase and DNA was replicated.

In mitosis, separation of sister chromatids occurs during

anaphase.

Cyclins regulate progression through the cell cycle by

activating kinases

List 3 reasons that Cancer cells are cancerous

mutations in tumor-suppressor genes. mutations in proto-oncogenes. uncontrollable cell division.

Unlike DNA, RNA contains

uracil

The function of tRNA molecules is to

transport amino acids to mRNA

Which type(s) of RNA is(are) involved in protein synthesis?

messenger RNA, ribosomal RNA, and transfer RNA

Why is the RNA in the cytosol much smaller than the RNA in the nucleus?

Noncoding regions of RNA are removed in the nucleus.

What happens during the process of translation?

The cell uses information from messenger RNA to produce proteins.

The heart and blood vessels form from this (these) tissue layer(s).

mesoderm

What change happens to chromosome number during fertilization?

a change from haploid to diploid

In a normal body cell of a dogfish shark, there are 24 chromosomes. How many chromosomes are found in each of its gametes?

12

the cell labeled X in Figure 10-9 containing 4 chromosomes. Which of the four cells below it represents a healthy gamete that could be produced from this cell?

A

During which phase of meiosis do homologous pairs of chromosomes line up next to one another along the equator?

metaphase I

A coin is tossed three times. The probability that it will land heads up all three times is

1/8

Organisms that have two identical alleles for a particular trait are said to be

homozygous

The failure of chromosomes to separate during meiosis is called

nondisjunction

What principle states that during gamete formation genes for different traits separate without influencing each other’s inheritance?

principle of independent assortment

Colorblindness is more common in males than in females because

the allele for colorblindness is recessive and located on the X chromosome

Certain segments of DNA are more likely to move from one area of a chromosome to another. These segments are called

transposons

The purpose of gene therapy is to

cure genetic disorders

Earth’s atmosphere probably originated

from volcanic gases

List 3 explanations for the first organic molecules

Gases reacted with energy like lightning. From meteorites From hydro thermal vents

The surface of Earth 4.6 billion years ago would have been hostile to modern life list 3.

temperatures were extremely high. atmosphere was rich in carbon dioxide. tremendous amounts of ultraviolet radiation.