Chapter 15-17 Flashcards
Messenger RNA (mRNA)
Carries information specifying amino acid sequences of proteins from DNA to ribosomes.
Transfer RNA (tRNA)
Serves as adapter molecule in protein synthesis; translates mRNA codons into amino acids.
Ribosomal RNA (rRNA)
Plays catalytic (ribozyme) roles and structural roles in ribosomes.
Primary transcript
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.
Small nuclear RNA (snRNA)
Plays structural and catalytic roles in spliceosomes, the complexes of protein and RNA hat splice pre-mRNA.
SRP RNA
Is a component of the signal-recognition particle (SRP), the protein-RNA complex that recognizes the signal peptides of polypeptides targeted to the ER.
Small nucleolar RNA (snoRNA)
Aids in processing of pre-rRNA transcripts for ribosome subunit formation in the nucleolus.
Small interfering RNA (siRNA) and microRNA (miRNA)
Are involved in regulation of gene expression.
hybridization
mating, or crossing , of two true -breeding
varieties
P generation
(parental generation )The true-breed ing parent
F1 generation
the P generation (parental generation ),
and their hybrid offspring
dominant allele
determines the organism’s appearance
recessive allele
has no noticeable effect on the organism’s appearance.
monohybrids
a hybrid that is heterozygous with respect to a specified gene.
dihybrids
a hybrid that is heterozygous for alleles of two different genes
independent assortment
each pair of alleles segregates independently of other pairs of
alleles during gamete formation.
complete dominance
The type of inheritance in which both heterozygotes and dominant homozygotes have the same phenotype.
codominance
a single gene has more than one dominant allele.
incomplete
dominance
one allele masks the phenotypic expression of another allele at the same gene locus.
pleiotropy
genes that have multiple phenotypic effects
epistasis
a gene at one
locus alters the phenotypic expression of a gene at a second
locus.
quantitative characters
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
