1
Q
how large is an average sized cell
A
about 1/5 the size of the smallest dot you can put on a piece of paper
2
Q
what are the functions of the cell
A
- cell metabolism & energy use
- synthesis of molecules
- communication (produce & receive electrical & chemical signs)
- reproduction & inheritance
3
Q
what are cells called that transmit DNA during sexual intercorse?
A
gametes
4
Q
what structure or area of the cell contains the organelles?
A
the cytoplasm
5
Q
what are the functions of the plasma membrane
A
- separates intracellular from extracellular
- membrane potential (a charge) across the membrane from intracellular & extracellular ion concentrations
- glycocalyx
- fluid-mosaic model
6
Q
is inside the plasma membrane positively or negatively charged?
A
negatively
7
Q
what is the glycocalyx composed of
A
glycolipids (carbs & fat)
glycoproteins (carbs & pro)
8
Q
phospholipid bilayer
A
-hydrophilic head
-hydrophobic tail
9
Q
what does cholesterol do
A
the more cholesterol there is, the less “fluid” membrane (results in a more stable plasma mebrane)
10
Q
what do phospholipids do if the membrane is damaged?
A
they automatically repair
-membranes can fuse with each other
11
Q
do membranes have a fluid nature?
A
yes; things can freely move through it, it isnt rigid
12
Q
what are the types of membrane proteins?
A
- integral or intrinsic
- peripheral or extrinsic
13
Q
integral proteins
A
-also called intrinsic proteins
-extend into the membrane, usually from one side of it to another, but not always
-can form channels
14
Q
what can integral proteins form?
A
channels
15
Q
peripheral proteins
A
-asloc alled extrinsic
-attached to either the inner or outer surfaces of the lipid bilayers
16
Q
what does the membrane proteins functioning depend on?
A
the 3D shape & chemical characteristics
17
Q
plasma membranes are made of all of the following except:
a. protein
b. glycoprotein
c. lipids
d. dna
A
dna
18
Q
in the fluid mosaic model, the double layer (bilayer) of molecules found in the cell membrane is made up of
a. cholesterol
b. phospholipids
c. carbs
d. proteins
A
b. phospholipids
19
Q
do membrane proteins mater ? (mind tag)
A
m-arker molecules
a-attachment proteins
t-transport proteins
e-enzymes
r-eceptors
20
Q
what are the marker molecules primarily composed of
A
glycoproteins
glycolipids
-the carbohydrate end is attached to either a protein or a lipid
21
Q
what do marker molecules do?
A
helps cells identify each other (or other molecules)
-immunity
-recognition of oocyte by sperm cell
-intracellular communication
22
Q
what are the types of attachement proteins?
A
-cadherind
-integrins
23
Q
what are cadherins
A
attachment proteins that link cell to cell
-cadherins on the surface of one cell link with identical proteins on the surface of neighboring cells.
24
Q
what are integrins
A
-attachment proteins
-they are integral proteins that attach to an extracellular molecule
-they sometimes allow communication due to contact with intracellular molecules
25
what are the types of transport proteins?
-channel proteins
-carrier proteins
-ATP powered pumps
26
what are the types of channel proteins?
-non-gated ion channels
-gated ion channels (consist of ligand-gated & voltage-gated)
27
what are non-gated ion channels
a type of channel protein that are always open
-the plasma membrane is permeable to a few ions when the plasma membrane is at rest
28
what are gated ion channels & what types are there
a type of channel proteins which are opened/closed by a stimuli
-ligand-gated
-voltage-gated
29
what are ligand-gated channels
a type of gated channel protein where a specific molecule is required to bind to the protein or glycoprotein to open/close the gate
30
what are voltage-gated channels
a type of channel protein where a change in charge across the plasma membrane is required to open/close the gate
31
what are carrier proteins also called
transporters
32
what are carrier proteins
they are integral proteins that move ions from one side of the membrane to the other side
-there are specific binding sites (protein changes shape then resumes original shape)
33
are there specific binding sites for carrier proteins?
yes!
-the protein changes shape for the ion then resumes original shape
34
what are the forms of carrier proteins?
1. uniporters
2. symporters
3. antiporters
35
what are uniporters
a form of carrier protein in which one ion or molecule is moved across the plasma membrane
36
what are symporters
a form of carrier protein where two different ions or molecules are moved in the SAME direction across the plasma membrane
37
what are antiporters
a type of carrier protein where two different ions or molecules are moved in opposite directions across the plasma membrane
38
what does the rate of transport depend on in ATP-powered transport?
concentration of ATP
38
what do ATP powered transports require
ATP
39
what do some membrane proteins function as?
enzymes
40
what are enzymes
they act to catalyze reaction at the outer/inner surface of plasma membrane
41
glucose+fructose
sucrose
42
protein in membranes have ______ sites
receptor sites
43
what do receptor sites enable
allows the proteins in the membrane to attach to specific chemical signals
-chemical signals (ligands) attach only to cells with a specific receptor
44
what do receptor proteins act as?
can act as an intercellular communication system
45
do cells have to have a specific receptor for a ligand to attach to?
yes!!
46
what are receptors linked to?
1. channel proteins
2. g protein complexes
47
what happens when receptors are linked to channel proteins?
1. attachment of receptor-specific chemical (ACh - a ligand) to receptors
2. channel opens (later closes)
3. changes the permeability of the cell
48
what happens with cystic fibrosis
defec in genes causes defects in channel proteins (look at that slide 3-41)
49
receptors linked to g protein complexes
1. alter activity on inner surface of plasma membrane
2. leads to intracellular chemical signals which affects cells (some hormones like insulin)
50
what are the ways of movement through a plasma membrane?
1. diffusion
2. osmosis
3. filtration
4. mediated transport
50
which way do things move in diffusion
involves the movement of solute in a solution
-higher concentration to lower concentration
51
what does diffusion involve
movement of solutes in a solution
52
what does diffusion depend on?
-concentration or density gradient: different between two points
-viscosity: how easily liquid flows
-temperature: affects movement of particles
53
what is osmosis
diffusion of water (solvent) across a selectively permeable membrane.
54
how does water move in osmosis
area of low concentration of solute to area of high concentration of solute
55
what are the comparative terms describing osmotic pressures of solutions
1. isosmotic: soltions with same concetrations of particles
2. hyperosmotic: solution with a greater concentration of solute
3. hyposmotic- solution is lesser concentration of solute
56
what is osmotic pressure
the force required to prevent water from moving across a membrane by osmosis
57
what does large volume changes caused by water movement do to normal cell functions
disrupts
58
cells shrinking or swelling comparitive terms
1. isotonic: cell neither shirnks nor cells
2. hypertonic: cell shrinks (crenation)
3. hypotonic: cell swells (lysis)
59
suppose that a man is doing heavy exercise in the hot summer. he sweats profusely. he then drinks a large amount of water. after he drank the water, you would expect his tissue cells to:
swell
60
which was does pressure move in filtration
greater to lower
61
what can move through the sieve?
water or small molecules
-large molecules remain in blood
62
what type of essential molecules cannot enter the cell by diffusion?
amino acids & glucose
63
what is mediated transport done by
carrier proteins or channels in the cell membrane
63
what can not exist the cell by diffusion
many products of the cell like protiens
64
what are the characteristics of mediated transport
-specificity: single type of molecule
-competition: among molecules of similar shape
-saturation: rate of transport limited by number of carrier proteins
65
what is facilitated diffusion
done by a carrier or channel protiens
-does not require energy
-it is passive
66
does facilitated transport require energy
no!!!!!
67
what does facilitated diffusion do
moves large water soluble molecules to electrically charges molecules across the membrane
68
do facilitated diffusion go lower conc to higher OR higher conc to lower
higher concentration gradient to lower
69
does active transport require energy?
yes
-atp powered transport
69
what does the rate depend on in active transport
depends on the number of ATP-powered pumps & the availability of adequate ATP
70
what goes in & what comes out during facilitated diffusion
amino acids & glucose in & manufactured proteins out
71
what created electrical potentials across membranes
Na+/K+ exchange pump
-pushes ions against their concentration
72
what happens in secondary active transport
-ions or molecules move in same direction (symport) or different direction (antiport)
73
does the movement of glucose use a symport or antiport movement
symport
-conc gradient for Na+ provides energy to move glucose against its conc gradient into the cell
74
what is endocytosis
it's the uptake of material through the plasma membrane by the formation of a vesicle
-substances are internalized by the formation of a vesicle
75
pinocytosis
-type of endocytosis
-cell drinking
-small vesicles form with dissolved molecules inside liquids rather than particles
76
what are the types of endocytosis
-phagocytosis (cell eating of particles)
-pinocytosis (cell drinking)
-receptor mediated (cell eating or cell drinking)
77
receptor-mediated endocytosis
-specificity
-phagocytizes or pinocitizes only certain types of cells
78
exocytosis
-secretion expelled from a cell
79
what are the examples of exocytosis
-digestive enzymes secreted by pancreas
-mucous secreted by salivary glands
-milk secreted by mammary glands
80
what is cytoplasm
cellular material outside nucleus but inside the plasma membrane
81
what is the cytosol
the fluid portion of the cytoplasm
81
what does the cytoplasm consist of
-cytosol
-cytoskeleton
-cytoplasmic inclusions
-organelles
82
what does the cytosol contains
the cytoskeleton & the cytoplasmic inclusions
83
what is cytosol made of
a colloid-viscous solution containing dissolved ions & molecules & suspended molecules
84
what are the functions of the cytoskeleton
1. support the cell
2. hold nucleus & organelles in place
3. movement of cell organelles
4. shape of the cell
85
microtubules
-part of the cytoskeleton
-hollow tubulin
-internal scaffold, role in transport inside the cell, cell division, forming part of centrioles, spindle fibers, cilia & flagella
86
intermediate filaments
-part of the cytoskeleon
-provides mechanical strength to the cell (long neurons)
87
microfilaments
-part of the cytokeleon
-made of actin
-spiderweb
-structure, support for microvilli, muscle contractality, defines shape of the cell, allows some cell movement
88
what defines the shape of the cell
microfilaments
89
what does cytosol also include
cytoplasmic inclusions
-aggregates of chemicals that are produced or taken in by the cell
-dust, minerals, & die can also accumulate in the cell
90
cytoplasmic inclusions
aggregations of chemicals that are produced or taken in by the cell (lipid droplets, glycogen granules store energy rich molecules; pigment melanin colors in the skin, hair, & eyes). dust, minerals, & dyes can also accumulate in the cell
91
organelles
small specialized structures with specific structure & function
-most have membranes which separate the interior of organelles from the cytoplasm
92
nucleus
- membrane-mound
- lot of DNA is located here
93
what is used for the internal scaffold, transport, & cell division (centrioles & spindle fibers)
a. microfilaments
b. intermediate filaments
c. microtubule
94
what does the nucleus consist of
nucleoplasm, nuclear envelope, & nucleolus
95
chromosome
-dna plus proteins (histones)
96
during cell division, chromatin condenses into pairs of ________ called chromosomes. Each pair of ________ joined by ________-
1. chromatids
2. chromosomes
3. centromere
97
what are ribosomes
the site of protein synthesis
-in a large & small subunit
98
what are the types of ribosome
free floating: produce protein used in the cell
-attached (to ER): produce proteins that are secreted by the cell
99
what are the types of ER
smooth & rough
100
what type of ER has ribosomes attached
rough er
101
what does rough er produce
proteins produced & modified
102
what does smooth er produce
lipids & carbs
103
what is cisternae
interior spaces isolated from the rest of the cytoplasm
104
what does the golgi apparatus do
modifies, packages, & distributes proteins & lipids produced by the RER & SER for secretion or internal use
105
what do lysosomes contain
hyrdolytic enzymes
106
what do lysosomes do?
breakdown proteins, bacteria, amino acids, & lipids
107
how big are peroxisomes
smaller than lisosomes
108
what do peroxisomes contain
contain enzymes to break down fatty acids amino acids
109
what is a byproduct of peroxisome breakdown
hydrogen peroxide
110
what enzyme do peroxisomes contain & what does it do?
catalase
-breaks down hydrogen peroxide into water & oxygen
111
cell active in what have many peroxisomes?
detoxification
112
what specific cells probably have lots of peroxisomes
liver & kidney cells
113
what does the mitochondria do?
provides energy for the cell
114
what is the mitochondria the major site of
atp synthesis
115
what are the cristae in the mitochondria
the infoldings of the inner membrane
116
what is the matrix
the substance located inside the mitochondria
117
what happens when cell energy requirements increase
the mitochondria increase in number
118
T/F mitochondria contain DNA
true
119
where is ATP needed in the plasma membrane
near active transport things
120
what is the centrosome
specialized zone of cytoplasm near the nucleus that is responsible for microtubule formation
121
what is the centrosome closely invovled in
closely involved in determining cell shape & movement
122
the centrosome contains two organelles called __________
centrioles
123
before cell division, what happens to the centrioles?
the two centrioles double in number
124
what is cilia
appendages that project from the cell surfaces
125
what does the cilia do?
it moves materials over the cell surface
126
how many cilia are there per cell
one to one thousand per cell
127
what is the type of cilia stroke that moves stuff that shouldnt be there
power stroke
128
what is the cilia stroke called that doesnt do anything
recovery stroke
129
what is flagella
-it is similar to cilia but longer
-thing that moves the cell itself (ex: sperm cell)
130
how many flagella per cell
one usually
131
what is the microvilli & what does it do
extension of the plasma membrane
-increases cell surface area for absorption (found on kidney & intestine cells)
132
how many microvilli per cell
many on each cell
133
what is the size of microvilli
1/10th to 1/20th the size of cilia
134
what is a gene & what is it responsible for
the functional unit of heredity
-the transmission of the genetic traits from parents to offspring
135
what is the segment of a DNA molecule that specifies the structure of a protein or RNA molecule
gene
136
what are the types of genes?
1. structural
2. regulatory
137
what are structural genes
serve as a template for mRNA, code for amino acid sequence
138
what are regulatory genes
control which structural genes are transcribed in a given tissue
139
transcription
DNA (in multiples of 3 nucleotides) is used to form RNA
140
translation
synthesis of a protein at the ribosome using mRNA, tRnA, & rRNA
141
does transcription or translation happen in the ribosome
translation
142
what happnes in transcription
1. dna stands in nucleus are seperated
2. rna polymerase attaches to a dna nucleotide at the promoter region
3. rna polymerase helps form a mRNA chain using DA as a template
4. transcription ends at a nucleotide sequence
143
A goes with ___
G goes with ___
U
C
144
when is mRNA modified
after transcription & before it leaves the nucleus
-this process produces the functional mRNA used in translation to produce a protein
145
where does translation occur
on ribosomes
146
tRNA ______ match with mRNA ______. & a ________ ______ forms between the amino acids at the opposite end of the tRNA
1. anticodons
2. codons
3. peptide bonds
147
what type of bond forms between amino acids
peptide bonds
148
what is interphase
the phase between cell division
-replication happens here
149
mitosis results in what
mother cell going to two daughter cells
150
what are the stages of mitosis
prophase
metaphase
anaphase
telophase
151
what is cytokinesis
division of cell cytoplasm
152
what stage does cytokinesis begin in
anaphase & continues through telophase
153
old strands of DNA become templates for new strands ... what is that called
complementary strands
154
what adds nucleotides to the end of the growing strand
DNA polymerase
a&p
flashcards
Decks in class (21)
# Cards
-
chapter 169
-
a & p lab one40
-
chapter 262
-
chapter 3159
-
a + p lab 233
-
chapter 4184
-
chapter 5149
-
chapter 6144
-
a&p lab exam26
-
chapter 7142
-
chapter 9 (& some of 10)210
-
chapter 11219
-
chapter 12145
-
lab exam46
-
chapter 13126
-
chapter 15285
-
chapter 1694
-
chapter 1795
-
lab exam18
-
exam 6 q16
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chapter 18107
