Lecture 5 study guide

Question 1

Polymorphism

Answer 1

The occurrence of different forms among the members of a population, can be morphological, genetic, behavioral, physiological

Question 2

Genotype

Answer 2

The genetic constitution of an individual organism

Question 3

Phenotype

Answer 3

the expression of the genotype of an organism, may be influenced or even determined by the environmental conditions experienced by the organism

Question 4

Mutations

Answer 4

the prosses of alteration of a gene or chromosome and its product

Question 5

DNA

Answer 5

a serise of nucleotide base pairs

Question 6

Purines

Answer 6

The base pairs adenine and guanine

Question 7

Pyrimidines

Answer 7

the base pairs thymine and cytosine

Question 8

chromosomes

Answer 8

a single long coiled molecule of DNA

Question 9

gene

Answer 9

a sequence of DNA that is transcribed into RNA

Question 10

transcription

Answer 10

the proccess by which DNA is convered to RNA

Question 11

Translation

Answer 11

the procces which RNA is convered to protine

Question 12

Locus

Answer 12

a site on a chromosome occupied by a particular gene or base pair region

Question 13

exons

Answer 13

gene segments that code for a protine

Question 14

introns

Answer 14

non coding DNA segments that occur between exons

Question 15

Codon

Answer 15

a 3 base pair segment of RNA that codes for a particular protine

Question 16

Amino acids

Answer 16

the building blocks of protines that are linked together to form a polypeptide, coded for by RNA

Question 17

Allele

Answer 17

different forms of a gene

Question 18

Haplotype

Answer 18

A particular DNA sequence that differs by one or more mutations from homologous sequence

Question 19

Genetic Markers

Answer 19

Detectible mutations that geneticists use to recognize specific regions of chromosomes or genes

Question 20

Fixed

Answer 20

A mutation that has increased in frequency to the point that it is found in every individual in a population

Question 21

Wild Type

Answer 21

Fixed genes reflecting the typical genotype or phenotype of a population

Question 22

Base Pair substitution

Answer 22

a mutation that maps to a single locus often restricted to a single base pair

Question 23

transition

Answer 23

a type of base pair substitution whereby a pruine is substituted for a purine or a Pyrimidine for a pyrimidine

Question 24

Transversion

Answer 24

A type of Base pair substitution whereby a purine is substituted for a pyrimidine or vise vera

Question 25

Synonomous mutations

Answer 25

Mutations that have no effect on the resulting amino acid, polypeptide, or protein

Question 26

Nonsynonymous mutations

Answer 26

Mutations that result in amino acid substitutions thereby changing the structure and function of the resulting protine

Question 27

dn/ds ratio

Answer 27

the number of nonsynonymous mutations divided by the number of synonymous mutations, when the ratio is less then 1 nonsynonymous mutations are deleterious and removed by purifying selection, when the ratio is equal to 1 mutations are evolving neutrally, when its greater then 1 many of the nonsynonymous mutations were fixed by positive selection

Question 28

Frameshift mutations

Answer 28

a mutation that causes a shift in the reading frame such that the identity of amino acids occurring downstream of the mutation may be changed, the resulting polypeptide is usually greatly altered

Question 29

Insertion

Answer 29

a mutation whereby a single base pair is inserted into a DNA sequence

Question 30

Deletion

Answer 30

A mutation whereby a single base pair is deleted from a DNA sequence

Question 31

Recombination or crossing over

Answer 31

A normal process where genes are exchanged between chromosomes during meiosis

Question 32

Unequal crossing over

Answer 32

when 2 chromosomes are not perfectly aligned, results in tandem duplication on one chromosome and deletion on the other

Question 33

Pleiotropy

Answer 33

occurs when multiple phenotypic traits are affected by a single mutaiton

Question 34

Karyotpe

Answer 34

A description of the complement of chromosomes that includes number, size, shape, and internal arragnement

Question 35

Aneuploidy

Answer 35

unbalanced chromosome complement, usually results in inviability or poor development

Question 36

Polyploidy

Answer 36

changes in the number of whole sets of chromosomes

Question 37

Diploid

Answer 37

an organism with two entire sets of chromosomes

Question 38

polyploid

Answer 38

an organism with more then two sets of chromosomes