Diversity Of Life: Variation I And Ii

Front 1

genotype

Back 1

actual genetic instructions

Front 2

phenotype

Back 2

external expression of coded instructions

Front 3

homologous chromosome

Back 3

higher organisms that have two copies of each chromosome, one from each parent

Front 4

chromatid

Back 4

complete strand of DNA

Front 5

amino acid

Back 5

a linear series of amino acids make up protein

Front 6

protein

Back 6

made up of a linear series of amino acids

Front 7

enzyme

Back 7

enzymes are catalysts; control the direction of reactions, cause reactions to occur within a narrow range of temperature and pressure

Front 8

nucleotide

Back 8

attached to a backbone of sugar and phosphate molecules; form complementary base pairs

Front 9

DNA

Back 9

(deoxyribonucleic acid) - two strands in a coiled helix, each made up of a series of organic compounds called nucleotides

Front 10

RNA

Back 10

(ribonucleic acid) is a single strand of nucleotides

Front 11

messenger RNA (mRNA)

Back 11

moves from the nucleus out to the cytoplasm

Front 12

transfer RNA (tRNA)

Back 12

carries the amino acids to the ribosomes to be attached to the growing chain

Front 13

codon

Back 13

amino acids are coded for by a sequence of three nucleotides

Front 14

protein synthesis

Back 14

fhg

Front 15

nucleotide substitution

Back 15

one base pair accidently substitutes for another

Front 16

point mutation

Back 16

change at a single point along a strand of DNA

Front 17

chromosome mutation

Back 17

change in the amount of genetic information or rearrangement of genetic information

Front 18

polyploidy

Back 18

df

Front 19

chromosome deletion

Back 19

loss of part of the chromosome, can be fatal if both homologous chromosomes have same deletion

Front 20

chromosome duplication

Back 20

part of the homologous chromosome is duplicated - can lead to chemical imbalance, ex. too much of a particular enzyme is made

Front 21

chromosome inversion

Back 21

chromsome breaks in two, part of it flips around and refuses - extrememly rare, partial sterility often results

Front 22

chromosome translocation

Back 22

two non-homologous chromosomes break and exchange segments

Front 23

genetic recombination

Back 23

meiosis shuffles existing variations into infinite new combinations

Front 24

sexual recombination

Back 24

creates an incredible number of new beings from a relatively small number of alleles

Front 25

mitosis

Back 25

regular cell division; object is to make two identical diploid daughter cells

Front 26

meiosis

Back 26

object is to turn one diploid cell into four haploid daughter cells (gametes); two complete cell divisions

Front 27

haploid

Back 27

one of each type of chromosome

Front 28

diploid

Back 28

organism with two of each type of chromosome

Front 29

reduction division

Back 29

homologous chromosomes line up at the center of the cell; for a brief time they are physically joined together (chiasmata); one homologous chromosome goes to each daughter cell (random)

Front 30

independent assortment

Back 30

the direction each chromosome takes during reduction division is random

Front 31

crossing over

Back 31

during reduction division chromosomes are briefly joined, during this the process of exchanging genes or groups of genes is called crossing over

Front 32

genetic polymorphism

Back 32

beneficial for the evolution of the species