Eukaryotic Cell: structure and function

Question 1

Facilitated transport can be differentiated from active transport, because active transport requires –

Answer 1

an energy source

Question 2

The cell is the basic unit of function and reproduction, because sub cellular components cannot –

Answer 2

regenerate whole cells

Question 3

Dialysis is based on a – membrane that mimics the cell membrane and has physical pores of a specified size and resembles the function of the cell membrane

Answer 3

semipermeable

Question 4

glucose is a relatively large molecule and cannot freely diffuse through the plasma membrane but requires a – embedded in the membrane

Answer 4

transporter protein

Question 5

diabetes results from the inhibited release of – to facilitate the uptake of glucose by the cell

Answer 5

insulin

Question 6

T/F: water, small hydrophobic molecules, small ions, and neutral gas molecules can freely diffuse through the semipermeable membrane

Answer 6

true

Question 7

A protein that has several regions that contain 20-25 hydrophobic amino acids would most likely be a – protein

Answer 7

integral

Question 8

A membrane bound vesicle that contains hydrolytic enzymes is most likely a –

Answer 8

lysosome

Question 9

lysosome is the digestive region of the cell and is a membrane bound organelle with a low pH around – that stores hydrolytic enzymes

Answer 9

5

Question 10

vacuoles and vesicles are membrane bound sacs involved in the transport and – of materials that are ingested, secreted, processed or digested by cells

Answer 10

storage

Question 11

chloroplasts are the site of photosynthesis and are found only in – and plant cell

Answer 11

algae

Question 12

vacuoles are – than vesicles and are more likely to be found in plant cells

Answer 12

larger

Question 13

chloroplasts contain their own – and – and may have evolved via endosymbiosis in like mitochondria

Answer 13

DNA and ribosomes

Question 14

– are vesicles involved in the transport and storages of materials that are ingested by the cell through phagocytosis. The vesicles are formed by the fusion of the cell membrane around the particle

Answer 14

phagosomes

Question 15

a phagosome is a cellular compartment in which – can be digested

Answer 15

pathogenic microorganisms

Question 16

phagosomes fuse with lysosomes in their maturation process to form –

Answer 16

phagolysosomes

Question 17

A DNA damage checkpoint arrests cells in – transition

Answer 17

G1/S

Question 18

DNA damage checkpoint is a signal transduction pathway that blocks cell cycle progression in G1, G2, and metaphase and slows down the rate of – progression when DNA is damaged

Answer 18

S phase

Question 19

G-C base pairs are linked by – hydrogen bonds

Answer 19

3

Question 20

A-T base pairs are linked by – hydrogen bonds

Answer 20

2

Question 21

Because of complimentary base-pairing, double-stranded DNA has equal quantities of G = C (and T = A)

Answer 21

Chargaff’s rule

Question 22

Phospholipids contain a – backbone, a phosphate group and a simple organic molecule (choline)

Answer 22

glycerol

Question 23

phospholipid tails are forced to aggregate via –

Answer 23

hydrophobic forces

Question 24

phospholipid hydrophilic heads = glycerol and –

Answer 24

negatively charged phosphate group

Question 25

phospholipid hydrophobic tails usually consists of 2 long – (saturated or unsaturated) hydrocarbon chains

Answer 25

fatty acid

Question 26

– is embedded within the lipid bilayer in animals but absent in plant cell membranes

Answer 26

cholesterol

Question 27

the overall shape of a cell is determined by its –

Answer 27

cytoskeleton

Question 28

– is determined by the total concentration of dissolved particles in solution

Answer 28

osmolarity

Question 29

compounds that dissociate into ions increase the concentration of particles and produce a – osmolarity

Answer 29

increase

Question 30

to determine which molecule (after dissociation into ions) generates the highest osmolarity, determine the number of – each molecule dissociates into when dissolved in water

Answer 30

individual ions

Question 31

the two ribosomal subunits are produced in the –

Answer 31

nucleolus

Question 32

– are the site of protein production

Answer 32

ribosomes

Question 33

prokaryotic ribosomes subunits

Answer 33

30S and 50S = 70S

Question 34

eukaryotic ribosomes subunits

Answer 34

40S and 60S = 80S

Question 35

Golgi apparatus ia a membrane-bound organelle that modifies (glycosylation), sorts, and – proteins

Answer 35

packages

Question 36

rough ER is a portion of the endomembrane system that extends from the –

Answer 36

nuclear envelope

Question 37

rough ER is the site of production and – of proteins

Answer 37

folding

Question 38

misfolded proteins exit the rough ER and are sent to the – for degradation

Answer 38

proteosome

Question 39

– are phosphorylated proteins responsible for specific events during cell division, such as microtubule formation and chromatin remodeling

Answer 39

cyclins

Question 40

cyclins can be divided into four classes based on their behavior in the cell cycle: G1/S, S, – and G1 cyclins

Answer 40

M

Question 41

p53 is a – gene

Answer 41

tumor suppressor

Question 42

p53 or guardian of the genome plays a big role in conserving stability by preventing –

Answer 42

genome mutation

Question 43

a codon is a 3-nt segment of an – that hybridizes (via complementary base pairing) with the appropriate anticodon on the tRNA to encode for one amino acid in a polypeptide chain during protein synthesis

Answer 43

mRNA

Question 44

tRNA only interacts with the mRNA – the mRNA is bound to the ribosomal complex

Answer 44

after

Question 45

operon regulates the – of genes into mRNA and is not involved in the translation of mRNA into proteins

Answer 45

transcription

Question 46

peroxisomes are organelles found in most – cells

Answer 46

eukaryotic

Question 47

peroxisome breaks down very long chain fatty acids through –

Answer 47

beta-oxidation

Question 48

in animal cels, the peroxisome converts the very long fatty acids into medium chain fatty acids, which are subsequently shuttled to the – where they are eventually broken down via oxidation into CO2 and H2O

Answer 48

mitochondria

Question 49

T/F: RNA can be found in nucleus, mitochondria, prokaryotic cells, and ribosomes

Answer 49

true

Question 50

A vacuole is a membrane-bound organelle which is present in all – and – cells and some protist, animal, and bacterial cells

Answer 50

plant and fungal

Question 51

vacuoles are enclosed compartments filled with water and contain inorganic and organic molecules (including enzymes in solution) and may contain – that have been engulfed

Answer 51

solids

Question 52

the – and significance of vacuoles varies greatly according to the type of cell with greater prominence in plant cells

Answer 52

function

Question 53

phosphotransferase is needed to form the mannose-6-phosphate tag that targets hydrolase enzymes to their lysosomal destination. Defective phosphotransferase causes I-cell disease. Which defective organelle gives rise to this condition?

Answer 53

Golgi

Question 54

Golgi is part of the endomembrane system and serves as a cellular – center (packages, processes, modifies)

Answer 54

distribution

Question 55

smooth ER is part of the endomembrane system an dis connected to the nuclear envelope and functions in several – processes

Answer 55

metabolic

Question 56

smooth ER synthesizes

Answer 56

lipids, phospholipids, steroids

Question 57

cells that secrete lipids, phospholipids, and steroids such as the testes, ovaries, and skin oil glands have an extensive –

Answer 57

smooth ER

Question 58

smooth ER carries out metabolism of – and –

Answer 58

carbohydrates and steroids

Question 59

smooth ER detoxifies –

Answer 59

drugs

Question 60

smooth ER is responsible for the attachment of – on cell membrane proteins

Answer 60

receptors

Question 61

mitochondria and chloroplasts are unusual organelles because they contain – encoded proteins

Answer 61

nuclear and organelle encoded proteins

Question 62

the enzyme cytochrome c oxidase is a large – complex found in bacteria and mitochondrion of eukaryotes

Answer 62

transmembrane protein

Question 63

– is the last enzymes in the electron transport chain of mitochondria (or bacteria) located in the mitochondrial (or bacterial) membrane

Answer 63

cytochrome c oxidase

Question 64

cytochrome c oxidase receives an electron from each of four cytochrome c molecules and transfers the electrons to an O2 molecule, converting molecular oxygen to two molecules of –

Answer 64

H2O

Question 65

cytoskeleton is integral in proper cell division because it forms the – and is responsible for separating sister chromatids during cell division

Answer 65

mitotic spindle

Question 66

cytoskeleton is composed of – and –

Answer 66

microtubules and microfilaments

Question 67

cytoskeleton gives the cell mechanical support, maintains its shape and functions in cell –

Answer 67

motility

Question 68

mitochondria divide – to produce daughter mitochondria that incorporate some new nonradioactive and also inherit radioactive from the parent via semi conservation replication

Answer 68

autonomously

Question 69

T/F: post-translational import of proteins involve the Golgi complex

Answer 69

true

Question 70

width of animal cell

Answer 70

20 micrometers

Question 71

ribosomes are composed of specific rRNA molecules and –

Answer 71

associated proteins

Question 72

ribosomes are identified by the – coefficients (Svedberg units)

Answer 72

sedimentation

Question 73

peroxisomes contain the enzyme – that decomposed H2O2 into H2O and O2

Answer 73

catalase

Question 74

osmosis is a special type of diffusion involving water and is a form of – transport

Answer 74

passive

Question 75

high solute and low solvent concentrations

Answer 75

hypertonic

Question 76

low solute and high solvent concentrations

Answer 76

hypotonic

Question 77

solvents always flow spontaneously from an area of –

Answer 77

high solvent to low solvent concentration

Question 78

during osmosis, water flows rom a – to – environment

Answer 78

hypotonic to hypertonic

Question 79

after chromosome disjunction, cyclin B is marked for destruction by the –

Answer 79

anaphase promoting complex

Question 80

complex of Cdk and cyclin B is called a maturation or – promoting factor

Answer 80

mitosis

Question 81

– is necessary for the progression of the cells into and out of M phase

Answer 81

cyclin B

Question 82

mitochondria have their own DNA genetic material and – to manufacture their own RNAs and proteins

Answer 82

machinery

Question 83

T/F: all organisms that reproduce sexually inherit mitochondrial organelle from their mother

Answer 83

true

Question 84

mitochondrial genes cannot be – because all mitochondria are inherited from the mother

Answer 84

recessive

Question 85

– is involved in the synthesis of phosphatidylcholine

Answer 85

smooth ER

Question 86

examples of plastids

Answer 86

chloroplast and chromoplast

Question 87

– are site of manufacturing and storage of important chemical compounds used by the cell and often contain pigments used in photosynthesis

Answer 87

plastids

Question 88

plastids like prokaryotes contain a – double-stranded DNA molecule

Answer 88

circular

Question 89

mitochondrial mutations are often limited to one – type

Answer 89

tissue

Question 90

thyroid gland synthesizes – in response to high blood calcium levels

Answer 90

calcitonin

Question 91

calcitonin acts to reduce blood calcium, opposing the effects of –

Answer 91

parathyroid hormone

Question 92

calcitonin lowers blood Ca2+ by inhibiting the absorption of Ca2+ by –

Answer 92

intestines

Question 93

calcitonin lowers blood Ca2+ by inhibition of – activity in bones

Answer 93

osteoclast

Question 94

calcitonin lowers blood Ca2+ by inhibition of renal tubular reabsorption of Ca2+, allowing it to be –

Answer 94

excreted in urine

Question 95

kidneys are essential in the urinary system and serve homeostatic functions such as the regulation of – , maintenance of pH balance, and regulation of blood pressure (via salt and water balance)

Answer 95

electrolyes

Question 96

kidneys secrete – (involved in blood pressure regulation) that induces the release of aldosterone from the adrenal cortex

Answer 96

renin

Question 97

secretion of renin – blood pressure via sodium reabsorption

Answer 97

increases

Question 98

PTH – blood calcium

Answer 98

increase

Question 99

high levels of Ca2+ in bone and kidney involves – receptor

Answer 99

PTH 1

Question 100

high levels of Ca2+ in CNS, pancreas, testes, and placenta involves – receptor

Answer 100

PTH 2

Question 101

largest organ

Answer 101

liver

Question 102

T/F: liver function includes detoxification, protein synthesis, and production of biomolecules necessary for digestion

Answer 102

true

Question 103

liver synthesizes – which emulsifies lilies in the small intestine

Answer 103

bile

Question 104

rough ER is involved in the synthesis of – proteins

Answer 104

plasma membrane

Question 105

active protein involves a – and uses energy to move a substance across a membrane agains (up) a concentration gradient

Answer 105

carrier protein

Question 106

refers to how some ionic species can pass through the barrier while others cannot

Answer 106

Donnan equilibrium

Question 107

the presence of a different charged substance that is unable to pass through a membrane creates an –; the electrical potential arising between the solution is the Donnan potential

Answer 107

uneven electrical charge

Question 108

overexpression of cyclin D promotes an unschedules entry into –

Answer 108

S phase

Question 109

synthesis of cyclin D is initiated during – and drives the G1/S phase transition

Answer 109

G phase

Question 110

biochemical events lead to characteristic cell changes (morphology) and death which include – (irregular bulge in plasma membrane), cell shrinkage, chromatin condensation, nuclear fragmentation and chromosomal DNA fragmentation

Answer 110

blebbing

Question 111

programmed cell death

Answer 111

apoptosis

Question 112

traumatic cell death that results from acute cellular injury, whereas apoptosis conferees advantages during an organism’s life cycle

Answer 112

necrosis

Question 113

unlike necrosis, apoptosis produces cell fragments called – that phagocytic cells are able to engulf and quickly remove before the contents of the cell can spill out onto surrounding cells and cause damage

Answer 113

apoptotic bodies

Question 114

a failure in which stage of spermatogenesis produces nondisjunction that results in a male having a XXY?

Answer 114

anaphase I

Question 115

During meiosis anaphaseI, – separate

Answer 115

homologous chromosomes

Question 116

During meiosis anaphase II, – separate

Answer 116

sister chromatids (identical copies, except for recombination)

Question 117

In sperm, X and Y would be “homologous chromosomes” and would normally separate during meiosis I; failure to do so would create a sperm containing both X and Y which causes –

Answer 117

Klinefelter syndrome

Question 118

Anaphase is when the – splits and the homologous chromosomes/sister chromatids are drawn away (via spindle fibers) from each other toward opposite sides

Answer 118

centromere

Question 119

– is observed in females due to a single X karyotype (single X chromosome and lacking a Y)

Answer 119

Turner’s syndrome

Question 120

protein targeting occurs during the synthesis of which type of proteins?

Answer 120

secreting proteins

Question 121

most proteins that are secretory, membrane-bound, or targeted to an organelle use the – sequence of the protein to target the protein

Answer 121

N-terminal signal sequence (5-30 amino acids)

Question 122

the signal sequence of the polypeptide is recognized by a – while the protein is still being synthesized on the ribosome

Answer 122

signal recognition particle (SRP)

Question 123

protein synthesis pauses while the – is transferred to an SRP receptor on the ER (in eukaryotes) or to the plasma membrane (in prokaryotes) before translation of the polypeptide resumes

Answer 123

ribosome-protein complex

Question 124

free ribosomes produce proteins in the –

Answer 124

cytosol

Question 125

attached ribosomes produce proteins that are inserted into the –

Answer 125

ER lumen

Question 126

the concentration of growth hormone receptors will significantly reduce after selective destruction of –

Answer 126

plasma membrane

Question 127

all anterior pituitary hormones including GH are – hormones

Answer 127

peptide hormones

Question 128

peptide hormones are hydrophilic and cannot pass across the hydrophobic phospholipid bilayer, and therefore peptide hormones bind to receptors on the –

Answer 128

plasma membrane

Question 129

urea, a byproduct of amino acid metabolism, is a small uncharged molecule and therefore crosses the cell membrane by –

Answer 129

simple diffusion

Question 130

export of Na+ from a neuron is coupled with the import of –

Answer 130

K+

Question 131

the sodium-potassium-ATPase pump (ATP dependent process) is necessary for the maintenance of a – across the neuron membrane

Answer 131

voltage potential

Question 132

movement of Ca2+ into a muscle cell occurs against the concentration gradient and Ca2+ enters by – which requires ATP

Answer 132

active transport

Question 133

synaptic vesicles contain – and their exocytosis at a nerve terminus is an ATP-dependent process that is triggered by an action potential propagating along the neuron

Answer 133

neurotransmitters

Question 134

p53 is a tumor suppressor protein that regulates the cell cycle and prevents –

Answer 134

cancer

Question 135

– is 1/2 the mass of carbon and is a unit of convention for expressing the molecular mass of proteins

Answer 135

Dalton

Question 136

newly synthesized secretory protein: …. –> exterior of cell via exocytosis

Answer 136

rough ER, Golgi, secretory vesicles

Question 137

cholesterol is normally found dispersed in varying amounts throughout animal cell membranes in the irregular spaces between the – of the membrane

Answer 137

hydrophobic tails

Question 138

cholesterol – fluidity of the membrane because it confers stiffening and strengthening effects on the membrane

Answer 138

decreases

Question 139

proteins targeted to the Golgi from the rough ER have three destinations: –, transported into organelles or targeted to the plasma membrane as a receptor, channel or pore

Answer 139

secreted out of the cell

Question 140

the presence of – differentiates a protein from a carbohydrate molecule

Answer 140

nitrogen

Question 141

most abundant plasma protein

Answer 141

albumin

Question 142

because albumin is too large to pass from the circulatory system into the interstitial space, it is primarily responsible for the – of the circulatory system

Answer 142

osmotic pressure

Question 143

osmotic pressure is the force of H2O to flow from an area of – solute to – solute concentration

Answer 143

lower solute to higher solute concentration

Question 144

capillaries are – to albumin

Answer 144

impermeable

Question 145

increasing albumin solute concentration in the arteries/capillaries increases the movement of H2O from the interstitial fluid to – the osmotic pressure in the arteries/capillaries

Answer 145

reduce

Question 146

retinoblastoma protein (pRb or RB1) is a – that is dysfunctional in several major cancers

Answer 146

tumor suppressor protein

Question 147

one function of RB1 is to prevent – by inhibiting cell cycle progression until a cell is ready to divid

Answer 147

excessive cell growth

Question 148

RB1 also recruits several – such as methylases and acetylases

Answer 148

chromatin remodeling enzymes

Question 149

– prevents cells from replicating damaged DNA by preventing its progression along the cell cycle through G1 into S phase

Answer 149

RB1

Question 150

glycolysis occurs in the –

Answer 150

cytoplasm

Question 151

oxidation of pyruvate into acetyl-CoA and the Krebs (TCA) cycle occur in the –

Answer 151

mitochondrial matrix

Question 152

ETC (cytochrome) occurs in the –

Answer 152

inner membrane of the mitochondria

Question 153

ETC (H+ proton gradient) occurs in the –

Answer 153

inter membrane space of the mitochondria

Question 154

pyruvate is oxidized to acetyl-CoA as a preliminary step before joining – in the Krebs cycle, which occurs in the mitochondrion

Answer 154

oxaloacetate

Question 155

most abundant lipid in the body

Answer 155

triglycerides

Question 156

minerals (potassium, sodium, calcium, magnesium) are essential nutrients because they must be consumed in the diet and act as – (nonorganic components) for enzymes

Answer 156

cofactors

Question 157

T/F: minerals are digested by lysosomes

Answer 157

false

Question 158

recycling of organelles within the cell is accomplished through – by the lysosomes

Answer 158

autophagy

Question 159

albumins are – proteins

Answer 159

globular

Question 160

T/F: carotenoids and lecithin are lipid derivatives

Answer 160

true

Question 161

defective attachment of a chromosome to the spindle blocks the activation of the – complex

Answer 161

anaphase promoting

Question 162

in meiosis II, human cells have a single – copy of the genome

Answer 162

unreplicated

Question 163

centrioles are cylindrical structures composed mainly of –found in most eukaryotic cells (except flowering plants and fungi)

Answer 163

tubulin

Question 164

centrioles are involved int eh organization of the mitotic spindle and in the completion of –

Answer 164

cytokinesis

Question 165

centrioles contribute to the structure of the – and are involved in organizing microtubules in cytoplasm

Answer 165

centrosomes

Question 166

position of the centriole determines the position of the – and plays a crucial role in the spatial arrangement of the cell

Answer 166

nucleus

Question 167

– are the organizational sites for microtubules (i.e. spindle fibers) that assemble during cell division

Answer 167

centriole

Question 168

cAMP is a – triggered when a ligand (peptide hormone or neurotransmitter) binds to a membrane-bound receptor

Answer 168

second messenger

Question 169

through a G-protein intermediate, the – is activated and converts ATP into cAMP

Answer 169

adenylate cyclase

Question 170

adenylate cyclase is attached to the inner layer of the –

Answer 170

phospholipid bilayer

Question 171

placed in a hypertonic solution, erythrocytes will undergo – as osmotic pressure draws water out of the cell and the cell shrivels

Answer 171

crenation

Question 172

peroxisomes are abundant in the –

Answer 172

liver

Question 173

– are hollow proteins composed of tubulin monomers

Answer 173

microtubules

Question 174

microtubules are necessary for the formation of the – that separates chromosomes

Answer 174

spindle

Question 175

T/F: microtubules are necessary for the synthesis of cilia and flagella

Answer 175

true

Question 176

T/F: microtubules are necessary for the formation of the cell cytoskeleton within the cytoplasm

Answer 176

true

Question 177

actin and myosin are – fibers in muscle cells

Answer 177

contractile

Question 178

actin and myosin are composed of –

Answer 178

microfilaments

Question 179

a cell division where each of the two daughter cells receives a chromosome complement identical to that of the parent is –

Answer 179

mitosis

Question 180

– interfere with microtubule formation

Answer 180

colchicine

Question 181

amoeboid moves using pseudopodia which are bulges of cytoplasm powered but eh elongation of flexible – not microtubules

Answer 181

microfilaments

Question 182

microtubules are long, hollow cylinders made up of polymerized alpha and beta –

Answer 182

dimers

Question 183

T/F: apoptosis occurs both in fetal development and during ageing

Answer 183

true

Question 184

high level of DNA synthesis occur in cells such as – cells that use mitosis for rapid reproduction

Answer 184

skin cells

Question 185

coat-proteins like – are used to build small vesicles to safely transport molecules within and between cells

Answer 185

clathrin

Question 186

clathrin is a protein that is collected on the – side of the cell membrane and functions in the coordinated pinching off of membrane into receptor-mediated endocytosis

Answer 186

cytoplasmic

Question 187

a lipid-soluble toxin that inactivates clathrin results in – delivery of polypeptide hormones to endosomes

Answer 187

reduced

Question 188

in osmosis, H2O always flows from a region of – osmotic pressure to a region of – osmotic pressure

Answer 188

lower to higher