Biology Chapter 8

Question 1

Cell Division

Answer 1

A process in which a cell reproduces by splitting in two. The original cell and both new cells are all genetically identical.

Question 2

Chromosomes

Answer 2

The structures that contain most of a cell’s DNA

Question 3

Purposes of Cell division

Answer 3

1. Repairs damaged cells
2. Allows for growth
3. Allows for reproduction

Question 4

Asexual reproduction

Answer 4

reproduction by cell division (there is no egg fertilized by a sperm)

Question 5

Mitosis

Answer 5

The type of cell division responsible for asexual reproduction AND growth and maintenance of multicellular organisms.

Question 6

Sexual Reproduction

Answer 6

Fertilization of a egg by a sperm using a special type of cell division called meiosis

Question 7

Chromosome

Answer 7

A threadlike DNA molecule bearing thousands of genes

Question 8

What are chromosomes made out of?

Answer 8

Chromatin (DNA and protein molecules)

Question 9

Cell cycle

Answer 9

The ordered sequence of events that extend from the time a cell is first formed from a dividing parent cell to its own division into two cells

Question 10

Interphase

Answer 10

1 stage of cell cycle, cell performs its normal functions, doubles everything in its cytoplasm, and grows in size

Question 11

Mitotic phase

Answer 11

2nd stage of cell cycle, includes mitosis and cytokinesis

Question 12

Mitosis

Answer 12

1st part of mitotic phase, nucleus and its contents divide evenly into two daughter nuclei

Question 13

cytokinesis

Answer 13

2nd stage of mitotic phase, cytoplasm is divided in two

Question 14

meiosis

Answer 14

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

Question 15

haploid

Answer 15

gametes that have only one member of each homologous pair of chromosomes.

Question 16

diploid

Answer 16

cells containing two sets of chromosomes

Question 17

zygote

Answer 17

a diploid cell resulting from the fusion of two haploid gametes

Question 18

fertilization

Answer 18

Fusing male and female gametes to form a zygote

Question 19

Gamete

Answer 19

a mature haploid male or female cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote.

Question 20

Explain what is unusual about Komodo dragon reproduction.

Answer 20

There are two known instances of a female Komodo dragon reproducing asexually by parthenogenesis (they produced eggs that hatched young without a male being present).

Question 21

Describe the consequences of nondisjunction in autosomes and sex chromosomes.

Answer 21

• the members of a chromosome pair fail to separate at anaphase,
• producing gametes with an incorrect number of chromosomes.