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biology Flashcards

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1
Q

four fundamental tenets of cell theory

A

A - all living things are made of cells
B - basic fundamental unit of life
C - cells from from pre-existing cells
D - DNA

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2
Q

prokaryotic organisms are always ________, while eukaryotic organisms can be ________

A

single-celled
unicellular or multicellular

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3
Q

eukaryotic cells contain a _______ while prokaryotic cells do not have this

A

a true nucleus

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4
Q

in eukaryotic cells, most organells are _________

A

membrane bound

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5
Q

the membranes of eukaryotic cells consist of what

A

phospholipid bilayer

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6
Q

eukaryotic cells reproduce by _______

A

mitosis

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7
Q

linear DNA is wound around organizing proteins known as __ and is further wound into linear strands called ____

A

histones
chromosomes

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8
Q

rRNA is synthesized where

A

nucleolus

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9
Q

the inner membrane of mitochondria are arranged into infoldings called

A

cristae

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10
Q

cristae contain the molecs and enzymes of the ______, and also help to increase the ____ available for this as well

A

electron transport chain
surface area

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11
Q

mitochondria replicate independetnly how

A

binary fission

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12
Q

cytoplasmic or extranuclear inheritance is what

A

the transmission of genetic material independent of the nucleus

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13
Q

mitochondria are thought to have originated when

A

when the engulfing of an aerobic prokaryote by an anaerobic prokaryote resulted in a symbiotic relationship

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14
Q

mitochondria are also capable of killing the cell how

A

release of enzymes from electron transport chain - apoptosis

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15
Q

lysosomes are what

A

membrane bound structures containing hydrolytic enzymes that are capable of breaking down substrates

they function in conjunction with endosomes

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16
Q

endosomes do what

A

transport, package and sort cell material

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17
Q

the er is what

A

a series of interconnected membranes that are actually contiguous with the nuclear envelope

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18
Q

the rough er is studded with ___ which permit the translation of _____ destined for secretion directly into its ___

A

ribosomes
proteins
lumen

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19
Q

smooth er lacks ribosomes and is utilized primarily for _______ and the __ of certain drugs and poisons

A

lipid synthesis
detoxificationthe golgi

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20
Q

apparatus consists of _______

A

stacked membrane bound sacs

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21
Q

when inside the golgi apparatus, cellular products may be modified by the addition of groups like what

A

carbs
phosphates
sulfates

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22
Q

the golgi apparatus can also modify ceullular products through the introduction of what

A

SIGNAL SEQUENCES

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23
Q

cells that require a lot of energy or locomotion like sperm cells will have a lot of what

A

mitochondria

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24
Q

cells that are involved in secretion like pancreatic islet cells have high conc of what

A

RER

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25
Q

peroxisomes contain what

A

hydrogen peroxide

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26
Q

one of the primary functions of peroxisomes is the ___________. they also participate in the synthesis of ___ and contain some of the enzymes involved in the ____ pathway

A

breakdown of long chain fatty acids via beta-oxidation
phospholipids
pentose phosphate pathway

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27
Q

three components of cytoskeleton

A

microfilaments
microtubules
intermediate filaments

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28
Q

microfilaments are made of solid polymerized rods of _____

A

actin

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29
Q

actin filaments can also use ATP to generate force for movement by interacting with ___

A

myosin

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30
Q

microfilaments also play a role in __, by forming the _______ in mitosis, by oranizing into a ring at the site of division between two new daughter cells

A

cytokinesis
cleavage furrow

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31
Q

microtubules are hollow polymers of _ proteins

A

tubulin

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32
Q

microtubules provide the primary pathways along which motor proteins liek ____ and ___ carry vesicles

A

kinesin
dynein

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33
Q

cilia are __

A

projections from a cell that are primarily involved in the movement of materials alon ght esurface of the cell

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34
Q

flagella are

A

structures involved in mvmt of cell itself

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35
Q

9 + 2 structure

A

nine pairs of microtubules which form an outer ring, with two microtubules in the centre - structure of cilia and flagella

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36
Q

centrioles are found where and what are they

A

centrosome

organizing centers for microtubules and are structured as nine triplets of microtubules with a hollow centre

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37
Q

intermediate filaments include what

A

keratin, desmin, vimentin, lamins

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38
Q

intermediate filaments are involved in what

A

cell cell adhesion or maintenance of overall integrity of cytoskeleton

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39
Q

four tissue types

A

epithelial
connective
muscle
nervous

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40
Q

epithelial tissues cover the body and line its cavities, and in certain organs, are involved in ___________. they are tightly joined to each other and to an underlying layer of connective tissue known as the ___

A

absorption
secretion
sensation
basement membrane

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41
Q

in most organs, epithelial cells constitute the _______ - functional parts of organs

A

parenchyma

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42
Q

epithelial cells are often ______

A

polarized

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43
Q

simple epithelia
stratified
psuedostratified
cuboidal
columnar
squamous

A

one layer of cells
multiple layers
appear to have multiple layers - due to diffrences in height but are only one layer
cube
long and thing
flat and scalelike

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44
Q

whereas epithelial tissue contribute to the parenchyma of an organ, connnective tissues are the main contributos to the __ or support structure

A

stroma

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45
Q

in prokaryotes, dna is concentrated in an area of the cell called what

A

nucleoid region

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46
Q

three overarching domains into which all life is classified

A

archaea
bacteria
eukarya

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47
Q

which of the domains contain prokaryotes?

A

archaea and bacteria

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48
Q

historically, archaea were considered what

A

extremophiles

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49
Q

archaea contain a single circular ________, and divide by ______ or ________

A

chromosome
binary dission
budding

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50
Q

many antiobiotics target the bacterial ______, which is ______ than the eukaryotic one

A

ribosome
smaller

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51
Q

examples of mutualistic symbiotes

A

bacteria in human gut that produces vitamin K and biotin (B7) also help prevent growth of harmful bacteria

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52
Q

bacteria shape 3

A

cocci - spherical
bacilli - rod-shaped
spirilli - spiral shaped

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53
Q

the type of cell wall is determined by what

A

gram staining process
crystal violet stain, followed by counterstain with substance called safranin

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54
Q

if envelope absorbs crystal violet stain, it will be _ and is gram ___

A

deep purple
positive

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55
Q

if the envelop does not absorb the crystal violet stain, it will be __ and is gram _____

A

pink-red (absrosb safranin counterstain)
negative

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56
Q

gram positive cell walls consist of a thick layer of _____, a polymeric substance made from _____ and ______. in addition, the cell wall may also aid a bacterial pathogen by ________. it also contains ___ acid.

A

petidoglycan
amino acids
sugars
providing protection from host organism’s immune system
lipoteichoic

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57
Q

gram negative cell walls are very _ and also contain ____ in smaller amounts. these walls are separated from the membrane by the __ space. in addition to this, gram negative bacteria also have ______ containing ____ and _____. ___ are the part of gram negative bacteria that triggers an immune response in human beings

A

thin
petidoglycan
periplasmic
outer membranes
phospholipids
lipopolysaccharides
lipopolysaccharides

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58
Q

the inflammatory response to ___ is much stronger than the response to ___

A

lipopolysaccharides
lipoteichoic

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59
Q

the ability of a cellto detect chemical stimuli and move toward or away from them is called

A

chemotaxis

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60
Q

the hook in flagella do what

A

connects the filament and the basal body so that as the basal body rotates, it exerts torque on the filament which thereby spins and propels the bacterium forward

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61
Q

plasmids carry what

A

DNa that is not necessary for survival of the prokaryote

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62
Q

binary fission process

A

circular chromosome attaches to cell wall and replicates whi the cell continues to grow in size
eventually plasma membrane and ell wall begin to grow inward along midline of cell to produce two identical duaghter cells

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63
Q

in addition to genes that impart some benefit to bacterium, plasmids also carry

A

additional virulence factors = traits that increase pathogenicity - e.g. toxin production, projections that allow attachment to certain kinds of cells, or features that allow evasion of host’s immune system

64
Q

subset of plasmids is called ________ they are capable of integrating into the genome of the bacterium

A

episomes

65
Q

3 forms of genetic recombination

A

transformation
conjugation
transduction

66
Q

transformation describe

A

results from integration of foreign genetic material into host genome - foregin genetic material most frequently comes from other bacteria that spill their contents into civinity of bacterium

many gram negative rods are able to carry out this process

67
Q

conjugation describe

A

bacterial form of mating
two cells form a conjugation bridge, facilitates transfer of genetic material
transfer is unidirectional from donor male (+), to recipient female (-)
bridge is made from appendages called sex pili found on donor male

68
Q

the best studies sex factor in bacteria is what in what

A

fertility factor in e.coli
bacteria that have this are called f+ cells

69
Q

transduction describe

A

only genetic recombination process that requires a vector

bacteriophages can accidentally inforporate a segment of host DNA during assembly - when bacteriophage infects another bacterium, it can release this trapped DNA into new host cell

70
Q

transposons

A

genetic elements capable of inserting and removing themselves tfrom genome - has been seen in both pro and eu karyotes

if transposon is inserted within coding region of gene, gene might be disrupted

71
Q

lag phase

A

bacteria first adapting to new local conditions

72
Q

exponential phase/log phase

A

rate of divison increases

73
Q

stationary phase

A

reduction of resources slows reporduction

74
Q

the protein coat in viruses is known as what

A

capsid

75
Q

enveloped viruses are easier to kill t or f

A

t

76
Q

viruses must express and replicate genetic info within a host cell bc they lack

A

ribosomes to carry out protein synthesis

77
Q

tail sheath in bacteriophages can act like what and then what help the bacteriophage recognize and connect to correct host cell?

A

syringe - injects genetic material into bacterium
tail fibres

78
Q

postive sense is what

A

implies genome may be directly translated to functional proteins by the ribosomes of the host cells - just like mRNA

79
Q

negative sense RNA viruses are what

A

complicated - negative sense RNA strand acts as a template for synthesis of a complementary strand, which can then be used as a template for protein synthesis

80
Q

negative sense RNA viruses must carry an _________ in the virion to ensure that the complementary strand is syntheiszed

A

rna replicase

81
Q

retroviruses are what

A

enveloped, single stranded rna viruses

virion contains two identical rna molecules - carry an enzyme known as reverse transcriptase - synthesizes DNA from single stranded RNA

82
Q

HIV utilizies what kind of life cycle?

A

retrovirs

83
Q

most DNA viruses must enter the _ in order to be transcribed into ___

A

nucleus
mRNA

84
Q

genetic material from poitive=sense rna viruses stay in the __, where it is directly translated into __ by the ________. negative sense RAN viruses require syntehsis of a _______ via rna replicase, which can then be translated to form ____

A

cytoplasm
proteins
host cell ribosomes
complementary RNA strand
proteins

85
Q

viral progeny can be released how 3

A

initiate cell death, spilling of viral progeny
host cell may lyse
can leave cell by fusing with plasma membrane - extrusion

86
Q

lytic cycle

A

bacteriophage maximizes use of cell’s machinery with little regard for survival of host cell - viruses termed virulent

87
Q

lysogenic cycle

A

virus replicated as bacterium reproduces because now part of host’s genome

88
Q

prions

A

infectious proteins and non libing things

triggers misfolding of other proteins through conversion of protein from alpha helical structure to beta pleated sheet

reduces solubility of protein, as well as ability of cell to degrade protein

protein aggregates form eventually, interfering with cell fuctnion

cause mad cow disease, familiaal fatal insomnia

89
Q

viroids

A

small pathogens consisting of very short circular single stranded RNA that infect plants

bind to large number of RNA sequences and can silence genes in plant genome

prevents synthesis of necessary proteins - metabolic and strucutral damage to cell

90
Q

widest part of fallopian tube

A

ampulla

91
Q

what does the sperm form when in contact with secondary oocytes cell membrane?

A

tube like structure
acrosomal apparatus

92
Q

cortical rxn

A

release of calcium ions

93
Q

indeterminate cleavage vs determinate cleavage

A
  1. results in cells that can still develop into complete organisms
  2. cells with fates that are already determined
94
Q

chorion

A

extraembryonic membrane that develops into placenta

95
Q

allantois

A

extraembryonic membrane involved in early fluid exchange between embryo and tolk sac

96
Q

archenteron

A

membrane invagination into blastocoel

97
Q

opening of archenteron

A

blastopore

98
Q

deuterostomes, the blastopore develops into what and in protostomes what

A

anus
mouth

99
Q

ectoderm rise to

A

integument, epidermis, hair naisl epithelia of nose mouth lower anal canal lens of eye ns inner eare

100
Q

mesoderm rise

A

musuloskeletal circulatory excretoryd

101
Q

endoderm

A

internal organs

102
Q

adrenal cortex is derived from the ___ but the adrenal medulla is derived from the ____

A

mesoderm
ectoderm (bc it contains some nervous tissue)

103
Q

autocrine signals

A

act on same cell that secreted signal in first place

104
Q

paracrine signals

A

act on cells in local area

105
Q

juxtacrine signals

A

dont usually involve diffusion but involve a cell directly stimulating receptors of an adjacent cell

106
Q

endocrine signals

A

involve secreted horomes

107
Q

reciprocal development

A

differentiation of the lens then triggers optic vesicle to form the optic cup - ecomes retina

108
Q

axons carry neural signals ____ from soma, and dendrites carry signals _____ soma

A

away
toward

109
Q

axon hillock

A

integrates incoming signals - plays importnat role in action potentials

110
Q

oligodendrocytes and schwann in which system?

A

cns and pns respectively

111
Q

astrocytes

A

nourish neurons - form bbb

112
Q

ependymal cells

A

line ventricles of brain and produce cbf

113
Q

microglia

A

phagocytic cells inest and break down waste products and pathogens in cnsoligodendro

114
Q

cytes + schwann

A

produce myelin around axons

115
Q

neurons resting potential

A

-70mV - inside is neg relative to outside

116
Q

K+ conc inside cell avg

A

140mM
4mM outside cell

117
Q

potassium equilibrium potential

A

-90mV

118
Q

equilibrium potential for sodium

A

60mV

119
Q

temporal summation

A

multiple signals are integrated during relatively short period of timespa

120
Q

spatial summation

A

additive effects are based on number and location of incoming signals

121
Q

sodium channels being
closed
open
inactive

A

before cell reaches threshol and after inactivation has been reversed

from threshold to approx +35mV

from approx +35mV to resting potential

122
Q

difference between electrical and chemical transmission

A

withint a neuron, electricity is used to pass signals own the length of the axon

between neurons, chemicals are used to pass signals to subsequent neuron

123
Q

peptide hormones

A

amino acids - all derived from larger precursor polypeptides that are cleaved during posttranslational modification

124
Q

peptide hormones have ____ receptors and act via ____

A

surface
second messenger systems

125
Q

steroid hormones bind to ______ receptors and function by binding to ____ to alter gene transcription

A

intracellular
DNA

126
Q

where are steroid hormones derived from?

A

cholessterol
nonpolar molecules - can easily cross cell membrane

127
Q

the effects of ____ hormones are slower byt longer lived than ___ hormones bc they particilate in ____ causing alternations in amount of mRNA and protein present in a cell by direct action on DNA

A

steroid
peptide
gene regulation

128
Q

in the heart, impulse initiation occurs where

A

at the SA node

129
Q

all blood vessels are lined with _____ cells

A

endothelial

130
Q

the classical pathway requires what whereas the alternative pathway doesn’t

A

binding of an antiboyd to a pathogen

131
Q

MHC-1 pathway is called what

A

endogenous pathway

MHC 1 is all nucleated cells andpresente endogenous antiens

132
Q

exogenous pathway

A

MHC-II

antien presenting cells and presents exogenous antigens

133
Q

bladder has muscular lining known as what

A

detrusor muscle

134
Q

internal and external uretrhal sphincter muscles

A

internal = smooth contracted in onroamls state

external - skeletal muscle - under voluntary control

135
Q

micturition reflex

A

when bladder is full, stretch receptors convey to ns that bladder requires emptying - parasympatheti neurons to fire, and detrusor muscle contracts - also causes internal sphincter to relax

136
Q

hypodermis

A

layer of connective tissue that connext skin to the rest of bod

137
Q

arrector pili

A

muscles contract causing hairs of kin to stand up on end piloerection

138
Q

define
filration
secretion
reabsorption

A

mvmt of solutes from blood to filtrate at bowmans capsule

mvmt of solutes from blood to filtrate anywhere bsides bowmans capsule

movement of solutes from filtrate to blood

139
Q

countercurrent multiplier system

A

flow of filtrate through loop of henle is opposite direction from flow of blood through vasa recta

140
Q

ascending and descending loops of henle permeable to what

A

a = salts and impermeable to water

d = maximizes water reabsorption

141
Q

both smooth and cardaic muscle exhibit what activity

A

myogenic - respond to ns input but do not require exteranl signals to undergo contrction

142
Q

axial skeleton

A

skull vertebral column ribcage and hyoid bone

143
Q

appendicular skeleton

A

bones of the limbs pectoral girdle and pelvis

144
Q

tendons and ligaments

A

muscle to bone

bones together at joints

145
Q

longitudinal channels - axis parallel to bone

A

haversian canaels

146
Q

transverse channels (axis perpendicular to bone_

A

volkmann’s canals

contain blood vessles nerve fibres and lymph vesses that maintain helath of bone

147
Q

hardening of cartilage to bone

A

endochondral ossification

most long bones are formed like this

148
Q

intramembranous ossification

A

undifferentaiated embryonic connective tissue is transformed into and replaced by bone

occurs in bones of skull

149
Q

adductor

A

moves part of the body toward midline

150
Q

abductor

A

moves part of body away from midline

151
Q

penetrance

A

population measure defined as population of individuals in population carrying allele who actually express the phenotype

152
Q

expressivity

A

different manifesataions of same genotype across population

153
Q

mendels first and seconf law

A

segregation

independent assortment

154
Q

divergent parallel and convergent evolution

A

independene developemtn of dissimilar charactersitcs in two or more lineages sharing a common ancestor

process whereby related species evolve in similar ways for long period of time in respnse to analogous enviornmental selection pressures

independent development of similar characteristics in two or more lineages not sharing a recent common ancestor

155
Q
A

MCAT (6 decks)

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