Bio Exam 2

studied byStudied by 33 people
5.0(1)
get a hint
hint

Nucleotide Structure

1 / 61

Tags and Description

62 Terms

1

Nucleotide Structure

Has a sugar molecule, either a ribose in RNA or deoxyribose in DNA attached to a phosphate group and a nitrogen containing base

New cards
2

Complementary Nucleotides

how bases match on opposite DNA strands through hydrogen bonding on their nitrogenous bases

New cards
3

Semi-Conservative DNA Replication

one strand from each parent is conserved and remains intact after replication has taken place

New cards
4

Helicase

unzips the two strands of DNA, breaks through H-bond that bolds the bases together

New cards
5

Primase

makes the primer that allows DNA polymerase to figure out where to go, is make of DNA

New cards
6

DNA ligase

helps glue together DNA fragments

New cards
7

DNA Polymerase

replicates DNA molecules to build new strand of DNA, cannot figure out where to start without primer

New cards
8

Topoisomerase

split DNA strands in order to relive stress, untangle replicating DNA

New cards
9

Leading Strand

DNA replication occurs continuously

New cards
10

Lagging Strand

DNA synthesis restarts many times as the helix unwinds which results in Okazaki fragments

New cards
11

Telomere

an enzyme that adds extensions to the template strand where RNA primer can bind , found at the end of each chromosome

New cards
12

Advantages of mRNA

  • can make many mRNAs from one gene and can also make many proteins from one mRNA

  • can change whether or not to make mRNA from DNA and how much

New cards
13

Transcription Unit

a region of DNA used as a template for type of mRNA

New cards
14

Promoter DNA

where the RNA polymerase and cofactors bind and transcriptions begins, recognized and bound by proteins

New cards
15

Terminator DNA

where transcription ends, has specific nucleotides that are recognized and bound by proteins

New cards
16

Difference between replication and translation

replication requires a primer to begin, translation does not

New cards
17

snRNA

  • spliceosomes, proteins and small nuclear RNAs (snRNAs) removes introns

  • snRNAs bind, recognize specific nucleotides at exon-intron junctions

New cards
18

tRNAs

  • transfer RNAs, small stable RNAs w/ 70-80 nucleotides

  • each type binds to a specific type of amino acid

  • each type has 3 different nucleotides which is an anticodon

New cards
19

Start Codon

first codon of mRNA transcript translated by a ribsome

New cards
20

Stop Codon

a sequence of three nucleotides in DNA or mRNA that signals a halt to protein synthesis in the cell

New cards
21

Point Mutations

single base is added, deleted, or changed

New cards
22

Silent Mutations

base substitutions that result in no change of the amino acid or amino acid functionality when the altered mRNA is translated

New cards
23

Missense Mutation

a single base pair substitution alters the genetic code in a way that produces an amino acid that is different from the usual amino acid at that position; wrong amino acid

New cards
24

Nonsense Mutation

a sequence change gives rise to a stop codon rather than a codon specifying an amino acid

New cards
25

Frameshift Mutation

deletion or insertion of anything other than 3n (3, 6, 9, etc. ) nucleotides

New cards
26

Gene Expression in Prokaryotes

control of gene expression is mostly at the transcriptional level

New cards
27

Gene Expression in Eukaryotes

regulation of gene expression can occur at all stages in the process

New cards
28

Lac operon mRNA

makes proteins that help import the disaccharide lactose and break it down

New cards
29

DNA methylation

makes a chromosome more tightly packed because it makes DNA more attracted to itself and that limits gene expression

New cards
30

Histone acetylation

when amino groups are added to histone proteins, decreasing the attraction and making them unwind more, gene are more likely to be expressed more

New cards
31

Diploid Cell

2n, have pairs of homologous chromosomes

New cards
32

Haploid Cell

1n, have only one of each homologue, also gametes (eggs, sperm)

New cards
33

Sister chromatids

copies made by replication from one copy

New cards
34

Homologous chromosomes

not copies of each other, each inherited from a different haploid gamete

New cards
35

Gene

stretch of DNA that determines a certain trait, genes mutate and can take two or more alternative forms

New cards
36

Allele

one of the forms of genes

New cards
37

Meiosis I

meiotic spindle lines up homologous chromosomes next to each other, separates homologous chromosomes and sister chromatids stay together

New cards
38

Meiosis II

halves the amount of DNA, sister chromatids separate

New cards
39

Steps increasing genetic diversity

  • Crossing over

  • Random assortment of chromosomes

  • Random fusion of gametes from different parents

New cards
40

Mendel's Law of Segregation

the two alleles in the parent "segregate" from each other during the formation of gametes

New cards
41

Independent Assortment

two alleles of two or more different genes get sorted into gametes independently of one another

New cards
42

Incomplete Dominance

a mixture of the alleles in the genotype is seen in the phenotype.

New cards
43

Co-dominance

both alleles in the genotype are seen in the phenotype.

New cards
44

Nondisjunction

errors in chromosome separation during meiosis

New cards
45

Autosomal

a specific gene that is not on a sex chromosome

New cards
46

Sex-linked

traits that are influenced by genes carried on the sex chromosome

New cards
47

Polygenic Traits

characteristic like height or skin color that is influenced by two or more genes, does not follow the pattern for Mendelian inheritance

New cards
48

Quantative phenotype

measurable phenotype that depends on the cumulative actions of many genes and the environment

New cards
49

Complex Epistasis

interactions of genes that are not alleles, the suppression of one such gene by the other, complex interactions between genes and traits

New cards
50

Chiasmata

where non-sister chromatids remain physically connected at points of exchange, can result in the exchange of alleles

New cards
51

Synapsis

happens during prophase I when homologous chromosomes become connected

New cards
52

Crossing Over

exchange of genetic material and produces new allele combinations on chromosomes

New cards
53

Nondisjunction

errors in chromosome separation during meiosis

New cards
54

Trisonomy

person has three copies of one of the chromosomes instead of two (47 instead of 46)

New cards
55

Monosomy

person is missing one chromosome in the pair (45 instead of 46)

New cards
56

Barr body

inactivated, condensed X chromosome found in female cells, essential to regulate the amount X-linked gene product being transcribed

New cards
57

SRY gene

located at the distal region of the Y chromosome, is necessary for determining male sex determination

New cards
58

Transcription

process whereby the DNA sequence in a gene is copied into mRNA; the process whereby a base sequence of messenger RNA is synthesized on a template of complementary DNA

New cards
59

Splicing

parts of pre-mRNA (introns) are chopped out and remaining pieces (exons) are stuck back together

New cards
60

Operons

sequence of DNA containing a cluster of genes under the control of a single promoter

New cards
61

Promoter

upstream sequence to which RNA polymerase binds

New cards
62

Operator

segment of DNA to which repressor protein binds

New cards

Explore top notes

note Note
studied byStudied by 24 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 34 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 6 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 59 people
Updated ... ago
5.0 Stars(2)
note Note
studied byStudied by 95 people
Updated ... ago
5.0 Stars(2)
note Note
studied byStudied by 56 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 13 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 10 people
Updated ... ago
5.0 Stars(1)

Explore top flashcards

flashcards Flashcard20 terms
studied byStudied by 5 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard30 terms
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard96 terms
studied byStudied by 14 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard64 terms
studied byStudied by 17 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard45 terms
studied byStudied by 18 people
Updated ... ago
4.0 Stars(1)
flashcards Flashcard50 terms
studied byStudied by 2 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard100 terms
studied byStudied by 359 people
Updated ... ago
4.5 Stars(11)
flashcards Flashcard98 terms
studied byStudied by 14 people
Updated ... ago
4.0 Stars(1)