exam #3 vocab Flashcards Preview

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Flashcards in exam #3 vocab Deck (105)
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1
Q

chromosomes

A

the structures that contain most of the cell’s DNA

2
Q

asexual reproduction

A

the creation of genetically identical offspring by a single parent, without the participation of sperm and egg

3
Q

sexual reproduction

A

requires fertilization of an egg by a sperm

4
Q

gametes

A

egg and sperm
haploid
sex chromosome

5
Q

binary fission

A

dividing in half

6
Q

chromatin

A

fibers composed of roughly equal amounts of DNA and protein molecules

7
Q

sister chromatids

A

contain identical copies of the DNA molecule

- two sister chromatids are joined together especially thightly at a narrow “waist” called the centromere

8
Q

cell cycle

A

ordered sequence of events that extends from the time a cell is first formed from a dividing parent cell until its own division into two cell

9
Q

interphase

A

when a cell’s metabolic activity is very high and the cell performs its various function within the organism

10
Q

mitotic phase (M phase)

A

the part of the cell cycle when the cell actually divides, accounts for only about 10% of the total time required for the cell cycle

11
Q

mitotic spindle

A

football shaped structure of microtubules that guides the separation of the two sets of daughter chromosomes

12
Q

centrosomes

A

clouds of cytoplasmic material that in animal cells contain pairs of centrioles

13
Q

cleavage furrow

A

a shallow indentation in the cell surface

14
Q

growth factor

A

a protein secfreted by certain body cells that stimulates other cells to divide

15
Q

density-dependent inhibition

A

phenomenon in which crowded cells stop dividing

16
Q

cell cycle control system

A

cyclically operating set of molecules in the cell that both triggers and coordinates key events in the cell cycle

17
Q

tumor

A

an abnormally growing mass of body cells

18
Q

benign tumor

A

if abnormal cells remain at the original site, the lump is benign

19
Q

malignant tumor

A

can spread into neighboring tissues and other parts of the body, displacing normal tissues and interrupting organ function as it goes

20
Q

metastasis

A

spread of cancer cells beyond their original site

21
Q

carcinomas, sarcomas, lymphomas

A
  • skin or lining of the intestine (car)
  • tissues that support body, bone and muscle (sar)
  • bone marrow spleen and lymph nodes (lymph)
22
Q

somatic cell

A

typical body cell

23
Q

homologous chromosomes

A

two chromosomes of a matching pair

- they both carry genes controlling the same inherited characteresitcs

24
Q

locus

A

gene located at a particular place

25
Q

sex chromosomes

A

determine an individual’s sex

- male/female X/Y

26
Q

autosomes

A

the 22 remaining pairs of chromosomes

27
Q

life cycle

A

development of a fertilized egg into a new adult organism - sequence of stages leading from the adults of one generation to the adults of the next

28
Q

diploid

A

body cells contain pairs of homologous chromosomes

29
Q

haploid

A

cell with single chromosome set

n = 23

30
Q

fertilization

A

haploid sperm cell from the father fuses with a haploid egg cell from the mother

31
Q

zygote

A

fertilized egg and sperm

  • diploid
  • 2 sets of homologous chromosomes
32
Q

meiosis

A

type of cell division that producds haploid gametes in diploid organism

33
Q

crossing over

A

an exchange of corresponding segments between nonsister chromatids of homologous chromosomes

34
Q

chiasma

A

the sites of crossing over appear as x-shaped regions

35
Q

genetic recombination (recombinant)

A

the production of gene combinations different from those carried by the original parental chromosomes

36
Q

heredity

A

the transmission of traits from one generation to the next

37
Q

genetics

A

scientific study of heredity

38
Q

character

A

a heritable feature that varies among individuals, such as a flower color

39
Q

trait

A

each variant for a character, such as purple or white flower

40
Q

monohybrid cross

A

parent plants differ in only one character

41
Q

homozygous

A

two identical alleles for a gene

homozygotes for the trait

42
Q

heterozygous

A

organism that has two different alleles for a gene (heterozygotes)

43
Q

dominant

A

if two alleles of an inherited pair differ, then one determines the organisms appearance

44
Q

recessive

A

organism that has two different alleles for a gene

- heterozygote

45
Q

locus

A

each labeled band on the chromosomes

- specific location of a gene along chromosomes(loci)

46
Q

phenotype

A

physical trait

47
Q

genetype

A

genetic makeup

48
Q

dihybrid cross

A

mating of parental varieties differing in two characters

49
Q

complete dominance

A

the dominant allele has the same phenotypic effect whether present in one or two copies

50
Q

incomplete dominance

A

the appearance of F1 hybrid falls between the phenotypes of the two parental varieties

51
Q

codominant

A

both alleles are expressed in heterozygous individuals

52
Q

polygenic inheritance

A

the additive effects of two or more genes on a single phenotypic character

53
Q

sex-linked gene

A

gene located on either sex chromosome - X, Y

54
Q

molecular biology

A

study of heredity at the molecular level

55
Q

bacteriophages or phages

A

viruses that exclusively infect bacteria

56
Q

nucleotides

A

DNA and RNA are nucleic acids, consisting of long chains (polymers) of chemical units (monomers)

57
Q

DNA

A

deoxyribonucleic acid

58
Q

semiconservative model

A

in DNA replication where half of the parental molecule is maintained in each daughter molecule

59
Q

DNA polymerases

A

the enzymes that link DNA nucleotides to a growing daughter strand add nucleotides only to the 3’ end of the strand never to the 5’ prime
- grows 5’ - 3’

60
Q

DNA ligase

A

enzyme that links or ligates pieces of DNA into a single DNA strand

61
Q

transcription

A

synthesis of RNA

62
Q

translation

A

synthesis of protein under direction of RNA

63
Q

Function of gene

A

to dictate the production of a polypeptide

  • provide instructions for making specific proteins
  • does not build protein directly
64
Q

codons

A

genetic instructions for teh amino acid sequence of a polypeptide chain are written in DNA and RNA as a series of non over lapping three base “words”

65
Q

genetic code

A

set of rules that relate codons in RNA to amino acids in proteins

66
Q

RNA polymerase

A

a transcription enzyme that links the RNA nucleotides

67
Q

promoter

A

the “start trancribing” signal

- nucleotide sequence

68
Q

3 phase of transcription

A

1 initiation - attach rna polymerase to promoter and starts RNA synthesis
2 elongation - RNA grows longer - done RNA strand peels away and DNA strands come together again
3 termination - RNA polymerase reach a terminator and detaches from RNA molecule and gene

69
Q

mRNA

A
  • messenger RNA

- encodes amino acid sequences

70
Q

ribosomes

A

structures in the cytoplasm that position mRNA and tRNA close together and catalyze the synthesis of polypeptides

71
Q

mutation

A

any change in the nucleotide sequence of DNA

72
Q

silent mutation

A

some substitution mutations that has no effect at all

73
Q

lytic cycle

A

results in the lysis (breaking open) of the host cell and the release of the viruses that were produced within the cell

74
Q

lysogenic cycle

A

viral DNA replication occurs without destroying the host cell

75
Q

plasmid

A

a small, circular DNA molecule separate from the bacterial chromosome

76
Q

gene regulation

A

the turning on and off of genes

- can help organisms respond to environmental changes

77
Q

gene expression

A

the overall process by which genetic information flows from genes to proteins
- from genotype to phenotype

78
Q

the control of gene expression makes it possible for?

A

cells to produce specific kinds of proteins when and where they are needed

79
Q

differentiation

A

cells specialized in structure and function with each type of cell fulfilling a distinct role
results: body contains hundreds of different types of cells

80
Q

histones

A

small proteins that plays a crucial aspects with DNA packing

81
Q

nucleosome, linkers, tight helical fiber, thick supercoil

A

8 histones surrounded by DNA “bead”, that is joined by “linkers” strings which is wrapped into a tight helical fiber which is coiled into a thick supercoil

82
Q

epigenetic inheritance

A

inheritance of traits transmitted by mechanism not directly involving the nucleotide sequence

83
Q

alternative RNA splicing

A

organisms canproduce more than one type of polypeptide from a single gene

84
Q

regulation of gene expression

A

Breakdown of mRNA
initiation of translation
protein activation
protein breakdown

85
Q

reproductive cloning

A

cloning that results in the birth of a new living individual

86
Q

therapeutic cloning

A

when the major aim is to produce embryonic stem cells for therapeutic treatments

87
Q

oncogene

A

a gene which can cause cancer when present in a single copy in the cell

88
Q

proto-oncogene

A

a normal gene that has the potential to become an oncogene

89
Q

tumor suppressor genes

A

genes who’s normal products inhibit cell division

- help prevent uncontrolled cell growth

90
Q

biotechnology

A

the manipulation of organisms or their components to make useful products

91
Q

DNA technology

A

modern laboratory techniques for studying and manipulating genetic material

92
Q

Recombinant DNA

A

formed when scientists combine nucleotide sequences (pieces of DNA) from two different sources–different species– to form a single DNA molecule

93
Q

genetic engineering

A

direct manipulation of genes for practical purposes

94
Q

gene cloning

A

the production of multiple identical copies of a gene-carrying piece of DNA

95
Q

vector

A

gene carrier

96
Q

DNA ligase

A

joins DNA molecules by covalent bonds

97
Q

restriction enzymes

A

bacterial enzymes that are used as a cutting tool

98
Q

restriction site

A

the DNA sequence recognized by a particular restriction enzyme

99
Q

restriction fragments

A

the pieces of DNA produced by cuts made by restriction enzymes

100
Q

GMO

A

genetically modified organisms

- organisms that have acquired one or more genes by artificial means

101
Q

gene theraphy

A

alteration of an afflicted individuals genes for therapeutic purposes

102
Q

DNA profiling

A

the analysis of DNA samples to determine whether they cam e from the same individuals

103
Q

PCR

A

polymerase chain reaction

- a technique by which a specific segment of a DNA molecule can be targeted and quickly amplified in the laboratory

104
Q

gel electrophoresis

A

thin slab of jellylike material that acts as a molecular sieve that separate macromolecules (usually proteins or nucleic acids) on the basis of size, electrical charge or other physical properties

105
Q

cell division

A

when cell undergoes reproduction, the two daughter cells that result are gentically identical to each other and to the original parent cell