Biology 411 Final Exam

Front 1

Prokaryotic cells divide by a process known as ____________?

Back 1

Binary Fission

Front 2

What is the make-up of a“typical” prokaryotic genome?

Back 2

One ds circular DNA chromosome

Front 3

The FtsZ protein involved in prokaryotic celldivision shows “homology” to what eukaryotic protein?

Back 3

Tubulin

Front 4

Interphase of a eukaryoticcell cycle actually consists of what three phases?

Back 4

G1, S, and G2

Front 5

What is the major eventduring S phase?

Back 5

DNA replication/genome duplication

Front 6

What is the major event during M phase?

Back 6

Mitosis or meiosis/chromosome segregation

Front 7

What is the molecularcomposition of the “cell-cycle engine”

Back 7

CDK + cyclin

Front 8

What is CDK?

Back 8

Cyclin-dependent kinase

Front 9

What is the role of the“checkpoints” in the cell cycle?

Back 9

to ensure cell is ready to progress to next phase

Front 10

What is the name for the two products resultingfrom replication of a eukaryotic chromosome?

Back 10

Sister chromatids

Front 11

What holds sister chromatids togetherand when is this connection established?

Back 11

sister chromatid cohesionis made by cohesion complexes, established in S phase as chromosomes duplicate

Front 12

What is this?

Back 12

Human karyotype

Front 13

Distinguish haploid v.diploid

Back 13

haploid = one complete setof chromosomes (human = 23)

diploid = two complete sets(human = 46)]

Front 14

Know the components and connections for bothmitotic and meiotic spindle apparatus:

Back 14

Front 15

What segregate from eachother at the metaphase/anaphase transition of mitosis?

Back 15

Sister chromatids

Front 16

How many distinct sisterchromatids pairs attach and align at metaphase of mitosis in a human somaticcell?

Back 16

46.

Front 17

In a human cell atmetaphase of meiosis I, there are 23 distinct entities aligned at the metaphaseplate. What is the composition of each?

Back 17

a homologous pair of sisterchromatid pairs

Front 18

What holds homologous pair of sister chromatids together?

Back 18

Chiasma/synaptonemalcomplexes hold homologs; sister chromatid cohesion holds sister chromatids

Front 19

What is the major eventthat occurs during the “extended prophase” of meiosis I?

Back 19

MEI I - homologs disjoin;MEI II – sister chromatids segregate]

Front 20

What are two major ways bywhich meiosis generates genetic variation?

Back 20

independent assortment andrecombination

Front 21

Relate the events of meiosisto Mendel’s two “Laws”.

Back 21

First Law – Segregation =when homologs disjoin at M/A transition of Meiosis I;

Second Law – Independentassortment = when different homologous pairs attach/align/segregateindependently during MEI I]

Front 22

Be able to show the gametesproduced (and their relative ratios) by a dihybrid – like AaBb.

Back 22

1/4 AB, ¼ Ab, ¼ aB, ¼ ab

Front 23

How do you determine the genotypefor an individual that exhibits to phenotype conferred by the dominantallele?

Back 23

test cross by homozygousrecessive – e.g. B? X bbwill reveal what ? is

Front 24

Define “allele”.

Back 24

any different version orvariant of a gene, or any genetic unit

Front 25

What does it mean that twogenes are “linked”?

Back 25

on same chromosome

Front 26

Why do they exhibit“non-Mendelian inheritance”?

Back 26

because they do not assortindependently, rather dependently]

Front 27

What is the differencebetween a sex chromosome and an autosome?

Back 27

sex chromosomes differ intwo sexes and form the basis of determining what sex an individual is. autosomes are chromosomes that are found insame constitution in males and females

Front 28

In humans what is sexchromosome genotype of males?

Back 28

XY

Front 29

In humans what is sexchromosome genotype of females?

Back 29

XX

Front 30

What is basis of primarysex determining mechanism?

Back 30

female is default; maleoverride results from TDF gene in SRY region of Y chromosome -- soY is male-determining

Front 31

What is basis of thehallmark of X-linked inheritance – “carrier” females pass traits to affectssons?

Back 31

for recessivedisorders/traits, mothers are typically heterozygous, hence unaffected; sonsare hemizygous, hence show the trait (are “affected”) if they inherit the “affected”allele.

Front 32

Male and female mammalshave different “doses” of the X chromosome. Why is there not a dosage problem,as seen for the autosomes?

Back 32

dosage compensation –females inactivate one of two X chromosomes early in development, hence areeffectively ‘hemizygous’, like males

[NOTE: females are also said to be “mosaics” as a result of this process]

Front 33

What does it mean thatreplication of chromosomes in vivo (“in life”) is semi-conservative”?

Back 33

each parental strandserves as a template for a complementary new – or daughter – strand.

Front 34

The primary enzymeresponsible for chromosomal replication is __________________?

Back 34

DNA polymerase

Front 35

DNA polymerase can’t startnew strands. Instead this is accomplished by the enzyme ___________ whichsynthesizes short oligonucleotides termed __________________.

Back 35

primase; RNA primers

Front 36

These RNA primers areremoved and replaced with DNA nucleotides by _________________?

Back 36

DNA polymerase,synthesizing the ‘next’ segment of new synthesis]

Front 37

The final phosphodiesterbond is formed (“sealing the gap”) by _____________________?

Back 37

DNA ligase

Front 38

Ends of eukaryoticchromosomes present a unique challenge during replication because_____________?

Back 38

no way to remove ‘last’ RNAprimer at each end on lagging strand

Front 39

This problem is solved byan enzyme termed ______________?

Back 39

telomerase

Front 40

Replication starts atspecific sites termed ____________?

Back 40

origins or origins ofreplication

Front 41

A typical eukaryoticchromosome is {linear or circular?} and contains {one or many?} origins?

Back 41

linear; many

Front 42

The six-subunit proteincomplex that binds to eukaryotic origins is called the ____________?

Back 42

ORC – short for originrecognition complex

Front 43

Define monosomy andtrisomy.

Back 43

monosomy = 2n - 1, only onecopy of one chromosome; trisomy = 2n + 1; an extra copy (3) of one chromosome

Front 44

The primary cause of theseconditions is ___________________?

Back 44

non-disjunction at meiosis

Front 45

Whole genome analysisbegins with determination of complete genome sequence. What is “assembly” andwhy is it necessary?

Back 45

it is piecing together ofsmall segments of sequence (reads) into a complete sequence of each chromosome,assembled by identifying overlaps in the sequence of individual reads. It isnecessary because one sequence reaction produces at most approximately 1000 bpsof sequence information, far less than the content of a chromosome

Front 46

What is a contig?

Back 46

an intermediate step in theassembly process; a run of contiguous sequence consisting of several or manyoverlapping reads

Front 47

A major aspect of genomeannotation is protein prediction/identification. A major challenge to thiseffort in eukaryotic genome projects is presented by the presence of___________ that interrupt coding regions of genes.

Back 47

Introns

Front 48

Despite our greatercomplexity, we have about the same number of protein-coding genes in our genomeas invertebrates like nematodes and fruit flies. What two features help“explain” this seeming paradox?

Back 48

alternative spicing muchmore prominent in humans, produces more total proteins (many variants);non-coding RNA genes – many more in our genome

Front 49

the primary structure of a protein refers to

Back 49

amino acid sequence

Front 50

which of the following pertains to secondary structure of proteins

Back 50

alpha helix

Front 51

the overall 3D shape/structure of a protein is called _________ structure.

Back 51

tertiary

Front 52

which level of protein structure refers to the structure of a segment or region of protein

Back 52

secondary

Front 53

secondary structure in proteins results primarily from

Back 53

backbone interactions

Front 54

which of the following is a primary determinant of protein folding

Back 54

hydrophobic interactions

Front 55

codons in the genetic code consist of how many nucleotides?

Back 55

three

Front 56

what factors ensure the correct amino acid is attached to the correct tRNA?

Back 56

amino acyl tRNA synthetases

Front 57

which ribosomal subunit is responsible for "finding: the AUG start codon of the mRNA?

Back 57

small subunit

Front 58

during translation initiation in eukaryotes, where does the small subunit first bind to the mRNA?

Back 58

5' cap

Front 59

a biological membrane is composed primarily of a ________ bilayer

Back 59

lipid

Front 60

a lipid consists of three fatty acid chains attached by ______ bonds to a molecule of _______.

Back 60

acyl: glyercerol

Front 61

the lipids in biological membranes are actually phospholipids, with two non-polar fatty acids and one charged phospho-derived group. the result is a molecule that is said to be ___________.

Back 61

amphiathic

Front 62

a protein that is embedded in a membrane is termed a ________ membrane protein.

Back 62

integral

Front 63

passive transport across a membrane by diffusion relies on the existence of a concentration ____________.

Back 63

gradient

Front 64

which type of membrane transport requires the input of energy

Back 64

active

Front 65

cellulose is a long polymer of monosaccharides joined by ____ glycosidic bonds

Back 65

beta

Front 66

the nuclear envelope consists of a ________ membrane.

Back 66

double

Front 67

the ________ ER is the primary site of lipid biosynthesis in a eukaryotic cell.

Back 67

smooth

Front 68

small membrane-enclosed entities that shuttle things to and from the ER, golgi and plasma membrane are called _________.

Back 68

vesicles

Front 69

the nuclear envelope is so named because it:

Back 69

is a double membrane

Front 70

the rough endoplasmic reticulum has a "rough" appearance because its surface is decorated with:

Back 70

ribosomes

Front 71

which of the following is synthesized at the rough ER:

Back 71

membrane proteins

Front 72

the smooth ER is the primary site of biosynthesis of ____________.

Back 72

lipids

Front 73

proteins destined to be extracellular, synthesized on the rough ER, must pass through the _________ for further processing and transport to the cell surface for secretion.

Back 73

Golgi

Front 74

chloroplasts are the site of __________.

Back 74

photosynthesis

Front 75

the electron transport chain is found within invaginations of the inner membrane of what organelle?

Back 75

mitochondria

Front 76

proteins synthesized on rough ER are brought there through the action of the _______.

Back 76

SRP (signal recognition particle)

Front 77

proteins that localize to the nucleus do so because they contain an _________.

Back 77

NLS

Front 78

an organism that uses light energy for ATP synthesis is called a _____________.

Back 78

phototroph

Front 79

the Second Law of Thermodynamics states:

Back 79

entropy increases

Front 80

which of the following will contribute to making a reaction spontaneous?

Back 80

products lower energy than reactants

Front 81

oxidation involves

Back 81

loss of electrons

Front 82

photosynthesis captures light energy and converts it to chemical energy in the form of ________, the ultimate product of the entire process.

Back 82

glucose

Front 83

the cellular location of the photosynthetic electron transport chain is

Back 83

thylakoid membrane within the grana of the chloroplast

Front 84

the final products of the dark reactions, or Calvin cycle, in the chloroplast are

Back 84

triose phosphates

Front 85

the common name of the enzyme that catalyzes the first step of the calvin cycle, the most abundant enzyme in the world, is:

Back 85

rubisco

Front 86

the light reactions of photosynthesis produce ATP and reducing power (NADPH and FADH2), which are used to reduce CO2 to glucose. which of these is primarily responsible for the reduction of CO2 in the reduction phase of the calvin cycle

Back 86

reducing power

Front 87

cellular respiration involves the ______ of glucose to CO2 with concomitant generation of ATP

Back 87

oxidation

Front 88

the respiratory electron transport chain is located in the

Back 88

inner membrane of the mitochondria

Front 89

cell communication involving signalling at a distance is known as ___________ signalling.

Back 89

endocrine

Front 90

a signal molecule that binds in a specific fashion to a receptor is called a ______?

Back 90

ligand

Front 91

receptor activation in response to signal molecule binding often results from a ____________ shift in the receptor protein.

Back 91

conformational

Front 92

what physical property is commonly associated with ligands that bind to cell surface (transmembrane) receptors? they are ___________.

Back 92

polar

Front 93

activation of G protein-coupled receptors often results in the synthesis of cAMP, which is referred to as a _____________.

Back 93

second messenger

Front 94

activation of receptor tyrosine kinases upon ligand binding often involves ___________ of residues in the intracellular domain of the receptor.

Back 94

phosphorylation

Front 95

steroid hormones bind to their receptors in the ______ of the cell.

Back 95

cytosol

Front 96

epithelial cells form the ______ of many surfaces of the body (skin, intestine, blood vessels)

Back 96

lining

Front 97

microtubules are polymers composed of what protein subunit

Back 97

tubulin

Front 98

microfilaments are paired helices of ________ filaments.

Back 98

actin

Front 99

name two components of the cytoskeleton

Back 99

microfilaments and microtubules

Front 100

the motor protein associated with actin microfilaments is:

Back 100

myosin

Front 101

cell movement via cilia and flagella involves what component of the cytoskeleton and what motor protein?

Back 101

microtubules and dynein

Front 102

the major transmembrane protein responsible for cell-cell adhesion is:

Back 102

cadherin

Front 103

adherens junctions connecting two cells are anchored to what structure in the cytosol of each cell?

Back 103

actin microfilaments

Front 104

tight junctions are responsible for establishing tight junctions that seal the apical side of __________ cell layers.

Back 104

epithelial

Front 105

what type of cell-cell junction provides for direct exchange of material between the cytosol of each cell?

Back 105

gap junction

Front 106

the extracellular matrix consists of proteins and ________>

Back 106

polysaccharides

Front 107

the specialized extracellular matrix that underlies and supports epithelial cell layers is called the _________.

Back 107

basal lamina

Front 108

this component of the extracellular matrix is the most abundant protein in our body.

Back 108

collagen

Front 109

prokaryotes proliferate (undergo cell division) via:

Back 109

binary fission

Front 110

the FtsZ protein forms a ring at the site of contstriction and fission in bacteria. This protein exhibits significant homology to what protein found in eukaryotes?

Back 110

tubulin

Front 111

a "typical" eukaryotic genome consists of many _________ chromosomes.

Back 111

linear

Front 112

in its most basic form, the "cell cycle" consists of M phase and ___________.

Back 112

interphase

Front 113

After completion of M phase )cytokinesis) a newborn cell finds itself in what phase of the cell cycle?

Back 113

G1

Front 114

the duration of a "typical" eukaryotic cell cycle is approximately:

Back 114

20 hours

Front 115

The central regulator of the eukaryotic cell cycle is a heterodimer consisting of cyclin and:

Back 115

CDK

Front 116

The two chromosomes that are "the same" chromosome, one from your mother, the other from your father, are ____________ chromosomes.

Back 116

homologous

Front 117

the two products resulting from replication of a chromosome are sister ____________.

Back 117

chromatids

Front 118

a diploid human karyotype shows that all the chromosomes are displayed in pairs, largest to smallest. how many chromosomes are shown?

Back 118

46

Front 119

What is the phenotypic in the progeny of a dihybrid cross?

Back 119

9:3:3:1

Front 120

Mendel's Second law applies to:

Back 120

genes on different chromosomes

Front 121

how many different gamete genotypes will be produced by an individual of genotype AaBB?

Back 121

two

Front 122

When is Mendel's First Law (segregation) "satisfied" during meiosis?

Back 122

metaphase/anaphase transition of meiosis I

Front 123

the protein complex that assembles on centromeric DNA of eukaryotic chromosomes is called the:

Back 123

kinetochore

Front 124

linked genes refers to genes located:

Back 124

on the same chromosome

Front 125

bipolar attachment of homologs during prophase of meiosis I is stabilized by:

Back 125

chiasma

Front 126

the two DNA duplexes produced by replication of a eukaryotic chromosome are called:

Back 126

sister chromatids

Front 127

These twoDNA duplexes are hel together by:

Back 127

cohesin complexes

Front 128

These connections are established during:

Back 128

S phase

Front 129

The reason that X-linked disorders commonly pass from "carrier" mothers to "affected" sons, but not daughters, is that:

Back 129

sons are hemizygous for the X; receiving an X from the mother and a Y from the father

Front 130

life is what the _______________ surrounds itself with, to survive.

Back 130

genome

Front 131

name two ways meiosis generates genetic variation.

Back 131

independent assortment and genetic recomination

Front 132

in the semiconservative mode of DNA replication, each parental strand serves as a _______ for synthesis of a complementary daughter strand (or new strand).

Back 132

template

Front 133

the major enzyme responsible for replication of our genome is called _________?

Back 133

DNA polymerase

Front 134

since this enzyme can only add new nucleotides to the free 3' OH of a growing strand, it requires another enzyme, primase, to START new strands. what are these starting strands called?

Back 134

RNA primers

Front 135

ultimately, these RNA primers must be removed and replaced with DNA nucleotides. finally, an enzyme called DNA _______ "seals" the remaining gao by forming the last phosphodiester bond.

Back 135

ligase

Front 136

another problem encountered by the constrains of semiconservative replication catalyzed by DNA polymerase is termed "the problem of the ends." this problem arises because:

Back 136

no way to remove the "last RNA primer" on the lagging strand at each end.

Front 137

a genetic anomaly depicated as 2n + 1, involving an extra copy of ONE chromosome, is termed ______?

Back 137

trisomy

Front 138

this condition is caused by _________?

Back 138

non- disjunction at meiosis

Front 139

a major obstcle to whole genome sequence assembly is presented by _______?

Back 139

repetitive sequences in the genome

Front 140

a major challenge in annotation of predicted protein sequences in eukaryotic genomes is the presence of _______ that interrupt coding regions of genes.

Back 140

introns