Cell Structure Flashcards
1
Q
cluster of atoms held together by chemical bonds
A
molecule
2
Q
structure within a cell that performs a specific function
A
organelle
3
Q
simplest entity that has all the properties of life; a membrane-bounded unit containing DNA and cytoplasm
A
cell
4
Q
a group of similar cells that carry out a particular function
A
tissue
5
Q
structures composed of more than one type of tissue
A
organ
6
Q
related organs performing a common function
A
organ system
7
Q
an individual, independent, living entity
A
organism
8
Q
Cells are small to maintain a large – ratio in order to function
A
surface area to volume
9
Q
all prokaryotic cells have a plasma membrane, nucleoid, and cytoplasm containing –
A
ribosomes
10
Q
outside prokaryotic cells may be a –
A
cell wall
11
Q
bacteria’s cell wall contain –
A
peptidoglycan
12
Q
prokaryote that photosynthesizes?
A
cyanobacteria
13
Q
some prokaryotes swim using
A
flagella
14
Q
what is projected from the surface of prokaryotic cells that is involved in mating
A
pili
15
Q
eukaryotic cells contain an internal cytoskeleton that maintains – and moves materials
A
cell shape
16
Q
plant cell wall is mainly composed of
A
cellulose
17
Q
largest organelle; contains most of the cell’s DNA
A
nucleus
18
Q
nuclear envelope is made up of two membranes perforated by –
A
nuclear pores
19
Q
DNA is combined with protein to form –
A
chromatin
20
Q
when the nucleus is about to divided chromatin condenses and coils tightly forming –
A
chromosomes
21
Q
each chromosome (“colored body”) contains – which is comprised of many genes
A
one long molecule of DNA
22
Q
T or F: the nucleus may contain more than one nucleolus
A
True
23
Q
site of ribosome assembly
A
nucleolus
24
Q
fluid material within the nuclear envelope
A
nucleoplasm
25
a network of proteins which maintains shape of nucleus
nuclear lamina
26
all cells synthesize proteins on
ribosomes
27
3 locations of ribosomes in eukaryotes
1. free in cytoplasm
2. attached to ER
3. in energy-producing organelles (mitochondrial matrix, chloroplast stroma)
28
cells which synthesize proteins for export contain large amounts of --
ER
29
site for hydrolysis of glycogen
smooth ER
30
synthesis of steroids
smooth ER
31
makes proteins
rough ER
32
site for addition of short sugar chains to proteins (glycoproteins)
rough ER
33
cis Golgi apparatus lies closer to --
nucleus
34
trans Golgi apparatus lies closer to --
cell surface
35
modifies, packages, and sorts proteins
Golgi apparatus
36
synthesizes some polysaccharides for the cell wall
Golgi apparatus
37
vesicles from the rough ER fuse with the -- region of the Golgi apparatus and secretory vesicles are pinched off the the -- region
cis, trans
38
specific hydrophobic sequence of about 25 amino acids at the beginning of a polypeptide chains directs it into the ER
signal sequence
39
signal sequence is removed by --
an enzyme
40
converts energy from food in to ATP
mitochondria
41
the size of mitochondria is similar to
bacteria
42
the inner membrane of the mitochondria is highly folded forming --
cristae
43
part of the mitochondria that contains ribosomes and DNA
matrix
44
almost all eukaryotes contain mitochondria except those --
living in environments without oxygen
45
more mitochondria are present if cells are --
very active
46
plastids are present in --
plants and some proteins
47
serves for food manufacture or storage
plastids (e.g. chloroplasts carry out photosynthesis)
48
plastids are surrounded by -- membranes
2 unfolded
49
inner membrane of plastids form a stack of flattened disk-like sacs called
thylakoids
50
stacks of thylakoids are called
grana
51
chlorophyll is contained in the
thylakoid membrane
52
fluid within inner membrane of chloroplast
stroma
53
contain hydrolytic digestive enzymes
lysosomes
54
participate in phagocytosis
lysosomes
55
organelle that break downs and stores in plants and animals
peroxisomes
56
organelle that break downs and stores in plants only
glyoxysomes
57
vacuoles are present in plant cells and store -- and provide --
waste, turgor
58
maintains cell shape, facilitates cell movement and certain fibers act as tracks for "motor proteins"
cytoskeleton
59
organelle involved in support present in plants, fungi, bacteria, and some protists
cell wall
60
surround animal cells and is composed of protein (collagen, glycoproteins, and proteoglycan)
extracellular matrix
61
components of cytoskeleton
microfilaments, intermediate filaments, and microtubules
62
strands of actin
microfilaments
63
involved in movement during animal division
microfilaments
64
muscle contraction
microfilaments
65
tough, fibrous protein molecules twisted into rope-like structures, which stabilize cell structure
intermediate filaments
66
hollow cylinders made of tubulin
microtubules
67
involved in structure and function of cilia and flagella, centrioles and movement of cellular organelles
microtubules
68
motor proteins like -- and -- use energy from ATP to change their shape and move things
dynein and kinesin
69
All cells are bounded by a
plasma membrane
70
A plasma membrane provides a -- which has the ability to transport certain molecules
permeability barrier
71
The plasma membrane plays a key role in the --
response of cells to external stimuli
72
Plasma membranes are also involved in energy --
transduction
73
Membranes of composed of ---
lipids, proteins, and carbohydrates
74
-- provide physical integrity to membranes
lipids
75
-- perform specific functions for the membranes such as transport
proteins
76
-- serve as recognition sites on the cell surface
carbohydrates
77
phospholipids spontaneously form bilayer sheets in which the -- point inward
hydrophobic tails
78
as temperatures falls, lipid bilayer changes from a -- state to a -- state
fluid, rigid (gel)
79
if the hydrocarbon chains of a bilayer sheet are short or have double bonds then the temperature of the phase transition is --
lower
80
important component of plasma membrane of animal cells orients in bilayer with polar head group close to polar head group of phospholipid
cholesterol
81
the nonpolar interior of the lipid bilayer prevents passage of any -- molecules through the bilayer
water-soluble
82
permeability of water-soluble molecules occur because of --
specific protein molecules
83
explains how proteins are incorporated into the lipid bilayer
fluid mosaic model
84
on the outer surface of the plasma membrane carbohydrates are attached to --
proteins or phospholipids
85
-- proteins penetrate into the lipid bilayer
integral
86
most integral proteins are -- proteins that penetrate all the way through the bilayer
transmembrane
87
transmembrane proteins contain an alpha-helix of --- extending across the hydrophobic interior of the membrane
nonpolar amino acids
88
located outside the lipid bilayer on the cytoplasmic surface attached by non covalent bonds to the polar head groups of the lipid bilayer or to integral membrane proteins
peripheral proteins
89
covalently attached to a phospholipid or fatty acid embedded in the bilayer
lipid-anchored proteins
90
beneath the cytoplasmic surface of the red blood cell -- forms a mesh
spectrin
91
3 main roles of membrane proteins
1. transport proteins
2. receptors for molecular messengers from other cells
3. form junctions between cells
92
most carbohydrates in membranes are bound to proteins forming --
glycoproteins
93
-- form cell identity markers
glycolipids
94
cells recognize and bind to each other via --
surface membrane proteins
95
3 types of cell adhesion
tight junctions, desmosomes, and gap junctions
96
within cells, solutes distribute rapidly by -- due to the short distances involved
diffusion
97
movement is down the concentration gradient
diffusion
98
movement is against the concentration gradient
active transport
99
-- can diffuse across the lipid bilayer
small nonpolar molecules like oxygen and carbon dioxide
100
molecules with -- diffuse more rapidly
higher lipid solubility
101
diffusion of water molecules across a selectively permeable membrane
osmosis
102
water diffuse out of a cell
hypertonic
103
water diffuse into a cell
hypotonic
104
T or F: ions (Na+) being charged can readily cross membranes
false
105
ions pass through -- to cross membranes
aqueous channels created by intrinsic membrane proteins
106
certain molecules (glucose) bind to -- in the membrane and are transported across
carrier proteins
107
facilitated diffusion is -- and may become -- if all the protein carriers are in use
specific, saturated
108
-- active transport requires the direct participation of ATP
primary
109
-- active transport utilizes the energy in an ion gradient established by primary active transport
secondary
110
the sodium-potassium pump is an example of -- active transport
primary
111
transports macromolecules, large particles, and small cells into eukaryotic cells
endocytosis
112
in endocytosis, the -- envelops materials and forms a vesicle inside the cell
plasma membrane
113
large particles are engulfed
phagocytosis
114
small dissolved solutes or fluids enter a cell
pinocytosis
115
a specific membrane receptor binds to a particular macromolecule at sites called coated pits
receptor-mediated endocytosis
116
uptake of cholesterol in association with LDL is an example of -- endocytosis
receptor-mediated
117
materials in vesicles are secreted from the cell when vesicles fuse with the plasma membrane
exocytosis
118
first law of thermodynamics
energy cannot be created or destroyed
119
second law of thermodynamics
during any energy interconversion, some energy is released as heat which adds to the entry of the system
120
the sum of all chemical processes occurring within a cell or organism
metabolism
121
chemical reactions establish --
equilibrium
122
the -- is the ration of the concentration of products and reactants at equilibrium
equilibrium constant
123
a -- indicates that the reaction goes far towards completion
high equilibrium constant
124
the breaking of chemical bonds in the course of chemical reactions produces changes in --
Gibbs free energy
