Cell Ultrastructure and Cytoskeleton Flashcards
1
Q
2 major categories of organism
A
prokaryotes
eukaryotes
2
Q
organism with no nucleus, simple
A
prokaryote
3
Q
organism with a nucleus, new
A
eukaryotes
4
Q
examples of prokaryotes
A
monera
cyanobacteria
5
Q
examples of eukaryotes
A
protozoa
single-celled protists
mutlicelled metazoans
6
Q
prokaryotes: nucleus with nuclear envelope? membrane bound organelles? histones? DNA? Flagella? Cell Wall?
A
no no no circular lack axoneme unique
7
Q
eukaryotes: nucleus with nuclear envelope? membrane bound organelles? histones? DNA? Flagella? Cell Wall?
A
yes yes complexed with DNA organized into chromosomes axoneme present absent in animals, present in plants and fungi
8
Q
Cells contain __plasm (mostly water)
A
protoplasm
9
Q
Protoplasm in eukaryotes
A
cytoplasm
nucleoplasm
10
Q
semi-liquid contents between cell membrane and nuclear membrane, surrounds organelles
A
cytoplasm (cytosol)
11
Q
protoplasm within the nucleus
A
nucleoplasm
12
Q
contains genome of DNA
A
nucleus
13
Q
dna complexed with nucleoproteins forms ___.
A
chromatin
14
Q
packaged chromatin is ___.
A
chromosomes
15
Q
individual chromosomes contain ___
A
genes
16
Q
segments of DNA coding for particular traits
A
genes
17
Q
different forms of the same gene
A
allele
18
Q
In most eukaryotic cells, chromosomes exit as ___ pairs
A
homogenous
19
Q
homogenous pair number in humans
A
diploid (2n=46)
20
Q
homogenous pair number in eggs and sperm
A
haploid (n=23)
21
Q
sorting of chromosome pairs according to size and shape
A
karyotyping
22
Q
electron-DENSE, darkly -staining, INACTIVE DNA and nuceloproteins
A
heterochromatin
23
Q
permanently inactive DNA in females
A
barr body
24
Q
what does a barr body represent?
A
degenerate X chromosome; only 1 pair is active, other degenerates
25
dispersed DNA ACTIVE in transcription (RNA synthesis)
euchromatin
26
site of RNA transcription
nucleolus
27
Euchromatin is where cells are active in ____.
translation
28
most chromatin in nucleus is ___ ____.
INACTIVE heterochromatin
29
active portions of chromosomes unravel to become visible as "___ ___ _____"
lamp brush chromosomes
30
What are lamp brush chromosomes active in?
transcription and translation
31
what are the two types of nucleoproteins?
histones
| non-histones
32
most of DNA-associated protein in eukaryotes is this type of nucleoprotein
histone
33
what is the function of histones?
assist with DNA folding which organizes chromatin into chromosomes
34
segments of DNA that wrap around several histones
nucleosome
35
function of nucleosome
regulates DNA activity
36
What is the nucleus surrounded by?
nuclear envelope
37
function of the nuclear envelope?
separates nucleoplasm from cytoplasm
regulates exchange of macromolecules between nucleus and cytoplasm
38
What are the 2 layers in the nuclear envelope?
inner and outer nuclear membrane
39
what are the inner and outer nuclear membrane separated by?
perinuclear cisterna
40
What is the inner nuclear membrane associated with?
network of lamin filaments for support called nuclear lamina
41
What is special about the outer nuclear membrane?
studded with ribosomes and continuous with the rER
42
How are the inner and outer nuclear membranes connected?
nuclear pore complex (surrounds rings of proteins --> nucleoporins)
43
function of nucleoporins
form holes in membrane allowing transport of macromolecules
44
Ribosomes are BIPARTITE, or have 2 subunits. What are they?
40S
| 60S
45
characteristics of ribosomes
proteinaceous structures, contain rRNA
| synthesized and assembled in nucleolus
46
where are ribosomes found?
free in cytoplasm
attached to rER
outer nuclear membrane
47
site of protein synthesis (translation)
ribosomes
48
How does the mitochondria produce energy (ATP)
krebs cycle
| oxidative phosphorylation
49
Mitochondria is present in all cells except for:
RBCs
| keratinocytes
50
What is the effect of the lack of mitochondria in some cells?
limits life span of cell
51
How many membranes do mitochondria have?
2: inner and outer
52
Which membrane fo the mitochondria is permeable and what does it contain?
outer
| porin = pore forming protein
53
Which membrane of mitochondria is pleated to form folds, or cristae?
inner membrane
54
Which membrane of the mitochondria is lined with elementary particles?
inner membrane
55
What is the purpose of enzymes in the elementary particles of mitochondria?
oxidative phosphorylation
56
What is the inner cavity of the mitochondria filled with?
amphorous MATRIX material
57
What does the mitochondrial matrix contain and what is the purpose of it?
dense granules
| binding/storage sites for Ca
58
Do mitochondria contain linear or circular DNA?
circular
59
How do mitochondria replicate?
self-replicating
60
How do mitochondria reproduce and what is this most similar to?
binary fission
| similar to BACTERIAL divison
61
Are mitochondria inherited maternally or paternally?
maternally
62
Are mitochondria similar to eukaryotes or prokaryotes?
prokaryotes (endosymbiotic theory)
63
What process do cells rely on to get their energy?
cellular respiration
64
Energy is released from the (mechanical/chemical) breakdown of (organic/inorganic) from diet (proteins, carbohydrates, fats) stored in the form of ___.
chemical
organic
ATP
65
Where does cellular respiration begin?
| Glucose is converted to what in this process?
cytosol
| pyruvic acid
66
Where does cellular respiration occur and via what process?
cytoplasm
| ANAEROBIC glycolysis
67
What happens to pyruvic acid once it created in the cytosol?
diffuses into mitochondria
68
Is mitochondria this site of aerobic or anaerobic respiration?
aerobic
69
What part of the mitochondria contains enzymes of the krebs cycle and what is the formula?
matrix
| pyruvate --> CO2 + H2O + ATP
70
Where is the most ATP produced and how?
produced via OXIDATIVE PHOSPHORYLATION by CYTOCHROMES of the ELECTRON TRANSPORT SYSTEM (ETS)
71
enzymes that are found on the inner membrane of cristae:
cytochromes
72
Kreb's cycle and oxidative phosphorylation WITHIN the mitochondria both require ___, also know as ____ respiration.
oxygen
| aerobic
73
Aerobic respiration occurs in the _____, while anaerobic respiration occurs in the ____.
mitochondria
| cytoplasm
74
Krebs cycle/oxidative phosphorylation/glycolysis: which one undergoes anaerobic respiration?
glycolysis
75
series of membranous sheets and tubules throughout the cytoplasm
ER
76
This type of ER has surface receptor molecules for RIBOSOMAL attachment
rER
77
this type of ER specializes in protein synthesis
rER
78
What is the function of the smooth ER (sER)?
LIPID synthesis
transport of proteins from rER to Golgi
membrane formation and recycling
synthesis of cholesterol and steroid hormones
detoxification and conjugation of drugs and toxins
79
These organelles in the ER surround and coat proteins for transport, bud off sER, transport proteins between sER and Golgi and between Golgi and cell surface (also protect proteins)
coated vesicles
80
This organelle is a complex, flattened, stacked, membrane-bound cisternae
Golgi apparatus
81
What is the function of the Golgi apparatus?
post-translational modification, packaging, and sorting of proteins synthesized in the rER (sulfation, phosphorylation, glycoslyation)
82
The convex side of the Golgi network is aka the __ side and it is where proteins arrive from rER in _________.
cis
| coated transfer vesicles
83
The concave side of the Golgi network is aka the __ side and it is where proteins are packaged into ______________ for secretion.
trans
| clathrin-coated vesicles
84
Vesicles bud off maturing face as ____ ____, sorted into ____ ____ for extracellular export via exocytosis or as ______ ______ for intracellular use, or as _______ ______ for long-term storage.
condensing vacuoles
secretory vesicles
membrane-bound vesicles
secretory granules
85
during exocytosis and secretion, large amounts of intracellular membrane incorporated into outer cell membrane, recycled by Golgi:
membrane trafficking
86
membrane-bound vesicles containing hydrolytic enzymes (acid phosphatase)
lysosomes
87
newly formed lysosomes produced by rEr and Golgi are called:
1' lysosomes
88
Are 1' lysosomes active/inactive?
inactive
89
1' lysosomes fuse with phagocytic vesicles (or phagosomes) to form:
2' Lysosomes (or phagolysosomnes)
90
Are 2' lysosomes active or inactve?
active
91
Do 1' or 2' lysosomes function in intracellular digestion?
2'
92
Hydrolytic breakdown results in production of __ lysosomes, aka ___ ____
3'
| residual body
93
Which lysosomes may be excreted or remain in cells for life (lipofuscin pigment granules in neurons)
3'
94
Lysosomes also used to degrade organelles and cells with finite lifespans during _____.
apoptosis (aka autophagy)
95
programmed cell death
apoptosis
96
type of endocytic vesicles with acid pH in lumen
endosomes
97
What causes acid pH in lumen (endosomes)?
proton pumps in membrane, which pump H+ into interior, acidifying contents
98
membrane-bound organelles containing oxidative enzymes (oxidases)
peroxisomes (microbodies)
99
What do peroxisomes resemble and what do they contain?
lysosomes
| catalase and peroxidase
100
Peroxisomes use enzymes, free radicals, and hydrogen peroxide to do what?
Give an example of a location.
oxidize toxic metabolites
| kidney and liver cells
101
Name 3 membrane-bound vesicles:
lysosomes
endosomes
peroxisomes
102
non-living components of cell that include neural fat droplets, lipids, glycogen, secretory & pigment granules
inclusions
103
Type of inclusion that hides within host cells and can be intracytoplasmic or intranuclear
viral inclusions
104
Name 2 intracytoplasmic pigments:
melanin
| lipofuscin
105
black, brown, granular pigment; produced by melanocytes, transported to other cells
melanin
106
gold-brown granules; frequently seen in neurons; sometimes called "old-age pigment"
lipofuscin
107
What is the primary pigment in mammals?
melanin
