BIOLOGY Flashcards
(138 cards)
1
Q
membrane that surrounds the cell
A
plasma membrane
2
Q
components of the cytoplasm
A
proteins, lipids, ion channels, and other transport proteins
3
Q
True or False: The “head” of the phospholipid molecule is hydrophilic while the “tail” is hydrophobic.
A
TRUE
4
Q
term for a molecule that possesses both hydrophilic and hydrophobic molecules
A
amphipathic
5
Q
True or False: Both prokaryotes and eukaryotes possess a nucleus.
A
False, prokaryotes don’t have
6
Q
difference between integral (intrinsic membrane) proteins and peripheral (extrinsic membrane) proteins
A
integral proteins pass through the membrane while peripheral proteins are inside or outside of the membrane only
7
Q
proteins that anchor cells to neighbors or basal laminas
A
cell adhesion molecules (CAMs)
8
Q
proteins that actively transport ions across the membrane
A
pumps
9
Q
proteins that transport substances through electrochemical gradients by facilitated diffusion
A
carriers
10
Q
proteins that permit passage of ions in and out of the cell whenever activated
A
ion channels
11
Q
protein that binds messenger molecules to initiate physiological changes in the cell
A
receptors
12
Q
messenger molecules that are bound to receptors to initiate physiological changes in the cell
A
ligand
13
Q
proteins that catalyze reactions at the surface of the membrane
A
enzymes
14
Q
provides eukaryotic cells with the ability to form ATP
A
mitochondria
15
Q
process by which mitochondria forms ATP
A
oxidative phosphorylation
16
Q
True or False: The mitochondria plays a role in dysoptosis (programmed cell death).
A
False: apoptosis
17
Q
parts of the mitochondria
A
outer membrane, intermembrane space, cristae (inner membrane space), and central matrix space
18
Q
location of the enzyme complexes responsible for oxidative phosphorylation
A
along the cristae
19
Q
acidic organelle that is responsible for the digestion of external material (i.e. endocytosed bacteria) or worn-out cell components
A
lysosomes
20
Q
responsible for keeping the inside of the lysosome acidic
A
proton pump or H+ ATPase
21
Q
contains oxidases or catalases
A
peroxisomes
22
Q
enzymes that produce H2O2
A
oxidases
23
Q
enzymes that break down H2O2
A
catalases
24
Q
unique signal sequence that directs the proteins to the peroxisomes
A
peroxins
25
system of fibers that maintain the structure of the cell and permits it to change and move
cytoskeleton
26
components of the cytoskeleton
microtubules, intermediate filaments, microfilaments, and proteins
27
protein subunit of the microfilament
actin
28
protein subunit of the intermediate filament
several proteins
29
protein subunit of the microtubule
tubulin
30
rank the following in increasing diameter: microtubules, microfilaments, intermediate filaments
microfilaments, intermediate filaments, microtubules
31
molecular motors that move proteins, organelles, and other cell parts
kinesin, dynein, and myosin
32
duplicate themselves and moves apart from one another to the poles of the mitotic spindle; organizes the microtubules of the spindle
centrosomes
33
components of the centrosome
two centrioles and pericentriolar materials
34
used by unicellular organisms to propel themselves through liquids and multicellular organisms to propel mucus and other substances over various epithelia
cilia
35
type of junctions that tie cells together and endow tissues with strength and stability
tight junctions or zonula occludens
36
intercellular connections that also helps tight junctions hold cells together
desmosome and zonula adherens
37
intercellular connections that attach cells to the basal lamina
hemidesmosome and focal adhesions
38
tunnel for the diffusion of small molecules between two neighboring cells
gap junction
39
True of False: Tight junctions permit the rapid propagation of electrical energy from cell to cell and the exchange of various chemical messengers and intracellular signaling molecules.
False, gap junctions do these
40
True or False: The nucleus is present in all eukaryotic cells.
True
41
structures in the nucleus that carry a blueprint for all the heritable species and characteristics of the animal
chromosomes
42
giant molecule that makes up each chromosome
DNA
43
protein where DNA is wrapped around to form a nucleosome
histone
44
shortened version of the DNA
nucleosome
45
term for the whole complex of DNA and proteins
chromatin
46
ultimate units of hereditary traits
genes
47
patchwork of granules rich in RNA found in the nucleus
nucleolus
48
site of synthesis of ribosomes
nucleolus
49
structure where proteins are syntesized
ribosomes
50
surrounds the nucleus
nuclear membrane or envelope
51
space found in between the two folds of the nuclear envelope
perinuclear cisterns
52
complex series of tubules in the cytoplasm of the cell
endoplasmic reticulum
53
True or False: Ribosomes are present in the SER and absent in the RER
False, they are present in the RER and absent in the SER
54
site of protein synthesis and initial folding of polypeptide chains with the formation of disulfide bonds
rough (granular) endoplasmic reticulum
55
site of steroid synthesis in steroid-secreting cells and the site of detoxification processes in other cells
smooth (agranular) endoplasmic reticulum
56
collection of membrane enclosed sacs, responsible for processing, modifying, and packaging proteins and lipids
Golgi apparatus
57
True or False: Membranous vesicles with newly synthesized proteins fuse with the cistern on the trans side of the Golgi apparatus, through the middle cisterns, and exit through the cistern on the cis side.
False, enters the cis side, exits the trans side
58
tail of the sperm
flagella
59
crucial function of most cell divisions
distribution of DNA into two daughter cells (exception: meiosis)
60
term for a cell's DNA; it's genetic information
genome
61
True or False: Prokaryotic and eukaryotic genomes consist of one DNA molecule.
False, eukaryotic genomes consist of multiple DNA molecules
62
How many chromosomes do human somatic cells have?
46 chromosomes
63
How many pairs of chromosomes do human somatic cells have?
23 pairs of chromosomes
64
term for reproductive cells such as sperm and egg cells
gametes
65
How many chromosomes do gametes have?
23 chromosomes
66
When the cell is not dividing until it replicates in DNA in preparation for cell division, the DNA is in the form of what?
one single chromatin
67
True or False: After DNA replication, the chromosomes condense, with each chromatin fiber becoming densely coiled and folded, making the chromosomes longer so it can easily be seen in the microscope.
False, chromosomes become shorter
68
joined copies of the original chromosome
sister chromatids
69
protein complexes that attaches the sister chromatids together
cohesins
70
region in the sister chromatid made up of repetitive sequences where the DNA is attached most closely to its sister chromatid
centromere
71
region of the chromatid to either side of the centromere after the "waist"
arm
72
True or False: Once the sister chromatids separate, each chromatid is called a daughter chromatid.
False, each is called a chromosome
73
True or False: Mitosis refers to the production of somatic cells while meiosis refers to the production of gametes.
True
74
produces gametes
gonads (testes in males, ovaries in females)
75
Why do gametes only have 23 chromosomes?
Because during fertilization, male and female gametes merge to complete the 46 chromosomes.
76
two main phases of the cell cycle
mitotic (M) phase and interphase
77
True or False: The M phase is usually the longest phase of the cell cycle while interphase is considerable shorter.
False, the M phase is usually the shortest phase while interphase is considerably longer (90% of the cell cycle)
78
three phases of interphase
G1 phase (first gap), S phase (syntheses), and G2 phase (second gap)
79
main characteristic of the gap phases
cell growth
80
How does a cell grow before replicating?
production of proteins and cytoplasmic organelles such as mitochondria and endoplasmic reticulum
81
phase where duplication of chromosomes occur
S phase only
82
True or False: Cell growth occurs during gap phases only.
False, cell consistently grows throughout interphase
83
longest phase of interphase
S phase
84
five stages of mitosis
prophase, prometaphase, metaphase, anaphase, and telophase
85
completes the mitotic phase
cytokinesis
86
Explain what happens during mitosis.
key concepts: G2, prophase, prometaphase, metaphase, anaphase, telophase, cytokinesis
87
extends from the centrosomes during prophase
early mitotic spindle (microtubules)
88
plane equidistant between the spindle's two poles where the sister chromatids line up during cell division
metaphase plate
89
shortest stage of mitosis
anaphase
90
marks the beginning of anaphase
cohesins get cleaved in half
91
When does the mitotic spindle form?
prophase
92
What is the mitotic spindle comprised of?
microtubules and associated proteins
93
incorporated into the microtubules for polymerization (elongation) and removed for depolymerization (shortening)
tubulin
94
subcellular region containing material that organizes the cell's microtubules
centrosome
95
True or False: Losing the centrioles means that the cell cannot undergo mitosis.
False, plants don't even have centrioles so you don't need them
96
radial array of short microtubules extending from each centrosome
aster
97
What does the spindle consist of?
centrosome, spindle microtubules, and asters
98
structure made up of proteins that assembled on specific sections of DNA at each centromere
kinetochore
99
microtubules that attach to the kinetochore
kinetochore microtubules
100
True or False: A tug-of-war occurs when the kinetochore microtubules pull on the cohesins.
False, it happens when the microtubules pull on the kinetochore
101
True or False: Nonkinetochore microtubules attach to the opposite pole microtubules.
True
102
When is the spindle complete?
By metaphase, when the asters attach to the plasma membrane.
103
enzyme that cleaves the cohesins in two
separase
104
proteins on the mitotic spindle that pulls chromosomes apart
kinesin and dynein
105
process that causes cytokinesis to occur in animal cells
cleavage
106
shallow groove in the animal cell surface near the metaphase plate; first sign of cleavage
cleavage furrow
107
interacts with the myosin molecules, causing the ring to contract during cytokinesis
actin microfilaments
108
produced when vesicles derived from the Golgi apparatus move along microtubules to the middle of the plant cell
cell plate
109
True or False: All cells undergo cleavage.
False, plant cells do not have a cleavage furrow so it does not undergo cleavage
110
type of asexual reproduction of prokaryotes and single-celled eukaryotes where the cell grows twice its size then divides into two cells
binary fission
111
difference between binary fission in single-celled eukaryotes and prokaryotes
eukaryotes undergo mitosis, prokaryotes do not
112
cyclically operating set of molecules in he cell that triggers and coordinates key events in the cell cycle
cell cycle control system
113
control point in the cell cycle where stop and go-ahead signals can regulate the cycle
checkpoint
114
Where are the checkpoints in the cell cycle?
G1, G2, and M phases
115
protein that activates a kinase
cyclin
116
enzymes that play a crucial role in regulating the cell cycle and other cellular processes in eukaryotic cells
cyclin-dependent kinases (Cdks)
117
True or False: When there is a rise in cyclin activity, there is a drop in the activity of Cdks.
False, rise in cyclin leads to rise in Cdks
118
enzyme that triggers the cell's passage into M phase, past the G2 checkpoint
maturation-promoting factor (MPFs)
119
enzyme that promotes fragmentation of the nuclear envelope during prometaphase
maturation-promoting factor (MPFs)
120
enzyme that contributes to molecular events required for chromosome condensation and spindle formation
maturation-promoting factor (MPFs)
121
What happens when the cell does not pass the checkpoint at the G1 phase?
It switches to the G0 phase.
122
non-dividing state of the cell
G0 phase
123
checkpoint that determines when anaphase begins
M checkpoint
124
How does a cell pass the M checkpoint?
When all sister chromatids are aligned at the metaphase plate and properly attached to the spindles.
125
enzyme activated when the M checkpoint is passed
separase
126
protein released by certain cells that stimulates other cells to divide
growth factor
127
growth factor released by platelets whenever there is an injury
platelet-derived growth factor (PDGF)
128
growth factor responsible for the division and proliferation of fibroblasts during injury
platelet-derived growth factor (PDGF)
129
phenomenon where crowded cells stop dividing
density-dependent inhibition
130
exhibited by animal cells where to divide, they must be attached to something
anchorage dependence
131
catabolic process characterized by the partial degeneration of sugars or other organic fuel without the use of oxygen
fermentation
132
most efficient catabolic pathway; oxygen is consumed as a reactant along with the organic fuel
aerobic respiration
133
used by some prokaryotes where substances other than oxygen are used as reactants in a similar process that harvests chemical energy without oxygen
anaerobic respiration
134
term that includes both aerobic and anaerobic respiration
cellular respiration
135
formula for the process of aerobic respiration
organic compounds + O2 → CO2 + H2O + energy
136
transfer of one or more electrons from one reactant to another
redox reactions
137
loss of electrons from one substance in a redox reaction
oxidation
138
