Biology Chapter 8 Vocab

Question 1

Anaphase

Answer 1

The fourth stage of mitosis, beginning when sister chromatids
separate from each other and ending when a complete set of
daughter chromosomes arrives at each of the two poles of the cell.

Question 2

Asexual reproduction

Answer 2

The creation of genetically identical offspring

by a single parent, without the participation of sperm and egg.

Question 3

Autosome

Answer 3

A chromosome not directly involved in determining the sex
of an organism; in mammals, for example, any chromosome other
than X or Y.

Question 4

Benign tumor

Answer 4

An abnormal mass of cells that remains at its original

site in the body.

Question 5

Binary fission

Answer 5

A means of asexual reproduction in which a parent
organism, often a single cell, divides into two genetically identical
individuals of about equal size.

Question 6

Cancer

Answer 6

A disease characterized by the presence of malignant tumors
(rapidly growing and spreading masses of abnormal body cells) in the
body.

Question 7

Cell cycle

Answer 7

An ordered sequence of events (including interphase and
the mitotic phase) that extends from the time a eukaryotic cell is
first formed from a dividing parent cell until its own division into
two cells.

Question 8

Cell plate

Answer 8

A double membrane across the midline of a dividing plant

cell, between which the new cell wall forms during cytokinesis.

Question 9

Centromere

Answer 9

The region of a duplicated chromosome
where two sister chromatids are joined (often appearing as a narrow
“waist”) and where spindle microtubules attach during mitosis and
meiosis. The centromere divides at the onset of anaphase during
mitosis and anaphase II during meiosis.

Question 10

Clone

Answer 10

As a verb, to produce genetically identical copies of a cell, organism,
or DNA molecule. As a noun, the collection of cells, organisms,
or molecules resulting from cloning; colloquially, a single organism
that is genetically identical to another because it arose from the cloning
of a somatic cell.

Question 11

Crossing over

Answer 11

The exchange of segments between chromatids of
homologous chromosomes during synapsis in prophase I of meiosis;
also, the exchange of segments between DNA molecules in
prokaryotes.

Question 12

Cytokinesis

Answer 12

The division of the cytoplasm to form
two separate daughter cells. Cytokinesis usually occurs in conjunction
with telophase of mitosis. Mitosis and cytokinesis make up the
mitotic (M) phase of the cell cycle.

Question 13

Diploid

Answer 13

In an organism that reproduces sexually, a cell containing two
homologous sets of chromosomes, one set inherited from each parent;
a 2n cell.

Question 14

Duplication

Answer 14

Repetition of part of a chromosome resulting from fusion
with a fragment from a homologous chromosome; can result from an
error in meiosis or from mutagenesis.

Question 15

Gamete

Answer 15

A sex cell; a haploid egg or sperm. The union of two

gametes of opposite sex (fertilization) produces a zygote.

Question 16

Haploid

Answer 16

In the life cycle of an organism that reproduces sexually, a cell
containing a single set of chromosomes; an n cell.

Question 17

Homologous chromosomes

Answer 17

The two chromosomes
that make up a matched pair in a diploid cell. Homologous
chromosomes are of the same length, centromere position, and
staining pattern and possess genes for the same characters at corresponding
loci. One homologous chromosome is inherited from the
organism’s father, the other from the mother

Question 18

Interphase

Answer 18

The period in the eukaryotic cell cycle when the cell is not
actually dividing. Interphase constitutes the majority of the time
spent in the cell cycle

Question 19

Karyotype

Answer 19

A display of micrographs of the metaphase
chromosomes of a cell, arranged by size and centromere position.
Karyotypes may be used to identify certain chromosomal
abnormalities.

Question 20

Locus

Answer 20

The particular site where a gene is found on a chromosome.

Homologous chromosomes have corresponding gene loci.

Question 21

Malignant tumor

Answer 21

An abnormal tissue mass that can spread into

neighboring tissue and to other parts of the body; a cancerous tumor.

Question 22

Meiosis

Answer 22

In a sexually reproducing organism, the division
of a single diploid nucleus into four haploid daughter nuclei. Meiosis
and cytokinesis produce haploid gametes from diploid cells in the
reproductive organs of the parents.

Question 23

Metaphase

Answer 23

The third stage of mitosis, during which all
the cell’s duplicated chromosomes are lined up at an imaginary plane
equidistant between the poles of the mitotic spindle.

Question 24

Mitosis

Answer 24

The division of a single nucleus into two genetically
identical nuclei. Mitosis and cytokinesis make up the mitotic
(M) phase of the cell cycle.

Question 25

Mitotic spindle

Answer 25

A football-shaped structure formed of microtubules
and associated proteins that is involved in the movement of chromosomes
during mitosis and meiosis.

Question 26

Prophase

Answer 26

The first stage of mitosis, during which the chromatin
condenses to form structures (sister chromatids) visible with a light
microscope and the mitotic spindle begins to form, but the nucleus is
still intact.

Question 27

Sex chromosome

Answer 27

A chromosome that determines whether an individual

is male or female.

Question 28

Sister Chromatid

Answer 28

One of the two identical parts of a
duplicated chromosome in a eukaryotic cell. Prior to mitosis, sister
chromatids remain attached to each another at the centromere.

Question 29

Somatic cell

Answer 29

Any cell in a multicellular organism except a

sperm or egg cell or a cell that develops into a sperm or egg.

Question 30

Telophase

Answer 30

The fifth and final stage of mitosis, during which daughter
nuclei form at the two poles of a cell. Telophase usually occurs
together with cytokinesis.

Question 31

Zygote

Answer 31

The diploid fertilized egg, which results from the union

of a sperm cell nucleus and an egg cell nucleus.