New Unit Terms

Question 1

What are alternative forms of a gene that occupy the same locus on homologous chromosomes called?

Answer 1

Allele

Question 2

What is a condition where an organism has an abnormal number of chromosomes?

Answer 2

Aneuploidy

Question 3

What is any chromosome that is not a sex chromosome?

Answer 3

Autosome

Question 4

What is the thread-like structure composed of DNA and proteins that carries genetic information?

Answer 4

Chromosome

Question 5

What is the situation in which both alleles of a heterozygote are fully expressed in the phenotype?

Answer 5

Codominance

Question 6

What is the exchange of genetic material between homologous chromosomes during meiosis called?

Answer 6

Crossing over

Question 7

A chromosomal mutation involving the loss of a segment of a chromosome is known as _______.

Answer 7

Deletion

Question 8

What is a chromosomal mutation involving the repetition of a segment of a chromosome?

Answer 8

Duplication

Question 9

What is the gene interaction where one gene masks or modifies the expression of another gene?

Answer 9

Epistasis

Question 10

What is the unit of heredity that occupies a specific locus on a chromosome and codes for a particular trait?

Answer 10

Gene

Question 11

What term describes the genetic makeup of an individual, specifically the alleles it possesses?

Answer 11

Genotype

Question 12

What do we call an individual having two different alleles for a particular gene?

Answer 12

Heterozygous

Question 13

What are chromosomes that pair during meiosis and have the same genes at the same loci called?

Answer 13

Homologous chromosomes

Question 14

What term describes having two identical alleles for a particular gene?

Answer 14

Homozygous

Question 15

What is the situation where the heterozygote phenotype is intermediate between the two homozygous phenotypes?

Answer 15

Incomplete dominance

Question 16

What is a chromosomal mutation involving a reversal of a segment of a chromosome called?

Answer 16

Inversion

Question 17

What term refers to the tendency of genes located on the same chromosome to be inherited together?

Answer 17

Linkage

Question 18

What type of cell division produces haploid gametes?

Answer 18

Meiosis

Question 19

What type of cell division produces two genetically identical daughter cells?

Answer 19

Mitosis

Question 20

What is a permanent change in the DNA sequence of a gene called?

Answer 20

Mutation

Question 21

What is the process by which organisms with traits better suited to their environment survive and reproduce more successfully?

Answer 21

Natural selection

Question 22

What is a unit of gene expression in prokaryotes consisting of a promoter, an operator, and a series of structural genes?

Answer 22

Operon

Question 23

What term describes the observable characteristics of an organism?

Answer 23

Phenotype

Question 24

What is the phenomenon where a single gene affects multiple phenotypic traits called?

Answer 24

Pleiotropy

Question 25

What inheritance pattern involves a trait controlled by multiple genes?

Answer 25

Polygenic inheritance

Question 26

What is a chromosome involved in sex determination called?

Answer 26

Sex chromosome

Question 27

What term refers to the location of a gene on a sex chromosome?

Answer 27

Sex linkage

Question 28

What are two identical copies of a chromosome produced during DNA replication called?

Answer 28

Sister chromatids

Question 29

What is a cross between an individual with an unknown genotype and a homozygous recessive individual called?

Answer 29

Test cross

Question 30

What is a chromosomal mutation involving the transfer of a segment of one chromosome to another nonhomologous chromosome?

Answer 30

Translocation