Unit 3 Review: Multiple Choice

Question 1

Cell cycle-

Answer 1

Regular sequence of growth and division that cell undergo

Question 2

Mitosis

Answer 2

mitosis divides a cell’s nucleus into two nuclei, each with an identical set of DNA
Stage in the cell cycle where 1 thing of DNA is equally distributed between 2 identical daughter cells.

Question 3

Meiosis

Answer 3

Type of cell division where chromosomes number is reduced by half and the daughter cells are genetically distinct from the parents

Question 4

Interphase

Answer 4

Cell cycle when the cell grows, copies it’s DNA, and prepares to divide

Question 5

G1

Answer 5

the first period of interphase, cell doubles in size

Question 6

S

Answer 6

Cells are copying their nuclear DNA, before this stage DNA is stored loosely and stage S organizes it in the nucleus in 2 complete DNA sets.

Question 7

G2

Answer 7

Cells continue normal function and more growth, things must be in order before the next stage.

Question 8

Prophase

Answer 8

DNA and proteins condense into tightly coiled chromosomes. The nuclear envelope breaks down, centrioles begin to move to opposite poles, and spindle fibers form

Question 9

Metaphase

Answer 9

spindle fibers attach to each chromosome. They align the chromosomes along the cell equator

Question 10

Anaphase

Answer 10

Chromatids separate to opposite sides of the cell. Cytokinesis usually begins in late anaphase or teloph

Question 11

Telophase

Answer 11

Nuclear membranes start to form, chromosomes begin to uncoil, and the spindle fibers fall apart

Question 12

Purines

Answer 12

an organic molecule that has a double ring of carbon and nitrogen atoms
- adenine & guanine

Question 13

Pyrimidines

Answer 13

an organic molecule that has a single ring of carbon and nitrogen atoms.
- cytosine & thymine

Question 14

Nucleotides

Answer 14

parts in a nucleotide:
1. Sugar molecule
2. Phosphate group
3. Nitrogen containing base
one of 4 kinds:
- adenine - A
- guanine - G
- cytosine - C
- thymine - T

Question 15

Replication

Answer 15

the process of copying DNA in a cell

Question 16

Transcription

Answer 16

the process by which genetic info is copied from DNA to RNA

• The process of transcription makes copies of only one gene at a time
• Following transcription the RNA molecule moves through the nuclear membrane into the cytosol. Here it will direct the synthesis of proteins.

Question 17

Translation

Answer 17

the process of:
- genetic code —–> amino acids —–> proteins (nucleotides in RNA)

tRNA (transfer RNA) - transports amino acids to ribosomes

Question 18

Codon

Answer 18

a sequence of three nucleotides which together form a unit of genetic code in a DNA or RNA molecule

Question 19

mRNA

Answer 19

Messenger RNA (mRNA)- the type of RNA that carries genetic information from the nucleus to ribosomes to form proteins during translation.

Question 20

tRNA

Answer 20

Transfer RNA (tRNA) -the type of RNA that carries amino acids from the cytoplasm to the ribosome during transcription

Question 21

rRNA

Answer 21

Ribosomal RNA (rRNA) - the type of RNA found in ribosomes. It’s part of the ribosomes involved in making proteins during translation.

Question 22

protein synthesis

Answer 22

Proteins carry out the genetic instructions encoded in an organisms DNA. They are made of a sequence of amino acids linked together by peptide bonds.

Question 23

recombinant DNA/genetic engineering

Answer 23

the combination of DNA from 2 or more sources is called recombinant DNA

Question 24

Mutagenesis

Answer 24

the formation of mutations in DNA molecules. Ex: changes in the DNA sequence or rearrangement of the chromosomes

Question 25

Cloning

Answer 25

Clones are organisms that are exact genetic copies. Every single bit of their DNA is identical. Clones can happen naturally—identical twins are just one of many examples. Or they can be made in the lab. Mice, cattle and pigs are commonly cloned.

Question 26

polymerase chain reaction

Answer 26

The polymerase chain reaction (PCR) is a biomedical technology in molecular biology where a single copy or a few copies of a piece of DNA is amplified to make thousands to millions of copies of a particular DNA sequence.

Question 27

artificial selection

Answer 27

breeding of organisms by humans for specific phenotypic traits

Question 28

gene therapy

Answer 28

treating a genetic disorder by introducing a gene into a cell or by correcting a gene defect is called gene therapy

Question 29

stem cells

Answer 29

Stem cells are a class of undifferentiated cells that are able to differentiate into specialized cell
types. Commonly, stem cells come from two main sources:
Embryos formed during the blastocyst phase of embryological development (embryonic stem cells) and
Adult tissue (adult stem cells).