Chapter 15-17

Question 1

Messenger RNA (mRNA)

Answer 1

Carries information specifying amino acid sequences of proteins from DNA to ribosomes.

Question 2

Transfer RNA (tRNA)

Answer 2

Serves as adapter molecule in protein synthesis; translates mRNA codons into amino acids.

Question 3

Ribosomal RNA (rRNA)

Answer 3

Plays catalytic (ribozyme) roles and structural roles in ribosomes.

Question 4

Primary transcript

Answer 4

Serves as a precursor to mRNA, rRNA, or tRNA, before being processed by splicing or cleavage. Some intron RNA acts as a ribozyme, catalyzing its own splicing.

Question 5

Small nuclear RNA (snRNA)

Answer 5

Plays structural and catalytic roles in spliceosomes, the complexes of protein and RNA hat splice pre-mRNA.

Question 6

SRP RNA

Answer 6

Is a component of the signal-recognition particle (SRP), the protein-RNA complex that recognizes the signal peptides of polypeptides targeted to the ER.

Question 7

Small nucleolar RNA (snoRNA)

Answer 7

Aids in processing of pre-rRNA transcripts for ribosome subunit formation in the nucleolus.

Question 8

Small interfering RNA (siRNA) and microRNA (miRNA)

Answer 8

Are involved in regulation of gene expression.

Question 9

hybridization

Answer 9

mating, or crossing , of two true -breeding

varieties

Question 10

P generation

Answer 10

(parental generation )The true-breed ing parent

Question 11

F1 generation

Answer 11

the P generation (parental generation ),

and their hybrid offspring

Question 12

dominant allele

Answer 12

determines the organism’s appearance

Question 13

recessive allele

Answer 13

has no noticeable effect on the organism’s appearance.

Question 14

monohybrids

Answer 14

a hybrid that is heterozygous with respect to a specified gene.

Question 15

dihybrids

Answer 15

a hybrid that is heterozygous for alleles of two different genes

Question 16

independent assortment

Answer 16

each pair of alleles segregates independently of other pairs of
alleles during gamete formation.

Question 17

complete dominance

Answer 17

The type of inheritance in which both heterozygotes and dominant homozygotes have the same phenotype.

Question 18

codominance

Answer 18

a single gene has more than one dominant allele.

Question 19

incomplete

dominance

Answer 19

one allele masks the phenotypic expression of another allele at the same gene locus.

Question 20

pleiotropy

Answer 20

genes that have multiple phenotypic effects

Question 21

epistasis

Answer 21

a gene at one
locus alters the phenotypic expression of a gene at a second
locus.

Question 22

quantitative characters

Answer 22

An
either-or classification is impossible because the characters
vary in the population along a continuum (in gradations). such as human skin color and height