Chapter 13: Meiosis and Sexual Life Cycles

Question 1

asexual reproduction

Answer 1

the generation of offspring from a single parent that occurs without the fusion of gametes (by budding, division of a single cell, or division of the entire organism into two or more pasts). In most cases, the offspring are genetically identical to the parent.

Question 2

clone

Answer 2

(1) a lineage of genetically identical individuals or cells (2) in popular usage, an individual that is genetically identical to another individual (3) as a verb, to make one or more genetic replicas of an individual or cell

Question 3

diploid cell

Answer 3

a cell containing two sets of chromosomes (2n), one set inherited from each parent

Question 4

fertilization

Answer 4

(1) the union of haploid gametes to produce a diploid zygote (2) the addition of mineral nutrients to the soil

Question 5

gene

Answer 5

a discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses)

Question 6

gamete

Answer 6

a haploid reproductive cell, such as an egg or sperm. Gametes unite during sexual reproduction to produce a diploid zygote

Question 7

haploid cell

Answer 7

a cell containing only one set of chromosomes (n)

Question 8

hereditary

Answer 8

the transmission of traits from one generation to the next

Question 9

homologous chromosomes

Answer 9

a pair of chromosomes of the same length, centromere position, and staining that possess genes for the same characters at corresponding loci. One homologous chromosome is inherited from the organism’s father, the other from the mother. Also called homologs, or a homologous pair

Question 10

karyotype

Answer 10

a display of the chromosome pairs of a cell arranged by size and shape

Question 11

life cycle

Answer 11

the generation-to-generation sequence of stages in the reproductive history of an organism

Question 12

locus

Answer 12

a specific place along the length of a chromosome where a given gene is located

Question 13

meiosis

Answer 13

a modified type of cell division in sexually reproducing organisms consisting of two rounds of cell division but only one round of DNA replication. It results in cells with half the number of chromosome sets as the original cell

Question 14

meiosis I

Answer 14

the first division of a two-stage process of cell division in sexually reproducing organisms that results in cells with half the number of chromosome sets as the original cell

Question 15

meiosis II

Answer 15

the second division of a two-stage process of cell division in sexually reproducing organisms that results in cells with half the number of chromosome sets as the original cell

Question 16

recombinant chromosome

Answer 16

a chromosome created when crossing over combines DNA from two parents into a single chromosome

Question 17

sexual reproduction

Answer 17

a type of reproduction in which two parents give rise to offspring that have unique combinations of genes inherited from both parents via the gametes

Question 18

variation

Answer 18

differences between members of the same species

Question 19

zygote

Answer 19

the diploid cell produced by the union of haploid gametes during fertilization; a fertilized egg