the cell part 2 eukaryotic cells Flashcards
1
Q
what are eukaryotic organisms
A
protozoans, algae, fungi, plants, animals
2
Q
what are eukaryotic cells characterized by
A
the presence of membrane bound organelles in the cytoplasm
3
Q
what does the cytoskeleton hold in place
A
mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, peroxisomes
4
Q
what is the cytoskeleton
A
internal network that supports transport of intracellular components and helps maintain cell shape
5
Q
how is the genome of eukaryotic cells packaging different from eukaryotic cells
A
it is in multiple rod shaped chromosomes instead of a single circular chromosome
6
Q
describe the genome characteristics of bacteria
A
single chromosome
circular
haploid lacks histones
7
Q
describe genome characteristics of archaea
A
single chromosome
circular
haploid
contains histones
8
Q
describe the genome characteristics of eukaryotes
A
multiple chromosomes,
linear
haploid or diploid
contains histones
9
Q
how does bacteria divide cells
A
binary fission
10
Q
how does archaea divide cells
A
binary fission
11
Q
how do eukaryotes divide cells
A
mitosis, meiosis
12
Q
membrane lipid composition of bacteria
A
ester-linked
straight chain fatty acids
bilayer
13
Q
membrane lipid composition of archaea
A
ether-linked
branched isoprenoids
bilayer or monolayer
14
Q
membrane composition of eukaryotes
A
ester-linked
straight chain fatty acids
sterols
bilayer
15
Q
cell wall composition of bacteria
A
peptidoglycan or none
16
Q
cell wall composition of archaea
A
pseudopeptidoglycan or
glycopeptide or
polysaccharide or
protein
or none
17
Q
cell wall composition of eukaryotes
A
Cellulose (plants, some algae)
Chitin (fungi)
silica (some algae)
most other lack cell walls
18
Q
motility structure of bactera
A
rigid spiral flagella composed of flagellin
19
Q
motility structure of archaea
A
rigid spiral flagella composed of archaean flagellins
20
Q
motility structures of eukaryote cells
A
flexible flagella and cilia composed of microtubules
21
Q
ribosomes in bacteria and archaea
A
70s
22
Q
ribosomes in eukaryotes
A
80S in cytoplasm and rough ER
70S in mitochondria and chloroplasts
23
Q
what influences shape a eukaryotic cells
A
primary function
organization of cytoskeleton
viscosity of cytoplasm
rigidity of cell membrane
physical pressure exerted on it
24
Q
how is dna in a eukaryotic cell organized
A
condensed to fit in the nucleus and wrapped around histones
25
how are some protozoan nuclei different
they have to complete nuclei
one for reproduction and a larger one for cellular metabolism
26
what are heterokaryotic cells
cells in some fungi that are transiently formed with two nuclei
27
why are coenocytes
cells whose nuclei divide but the cytoplasm does not
28
what is the nucleus bound to
the nuclear membrane
29
what does the nuclear membrane consist of
two distinct lipid bilayers that are contiguous with each other
30
what does the nuclear membrane contain
nuclear pores that control the movement of materials into and out of the cell
31
describe nuclear pores
large, rosette-shaped protein complexes
32
what determines the shape of the nucleus
the nuclear lamina
33
what is the nuclear lamina
a meshwork of intermediate filaments found just inside the nuclear envelope membranes
34
what happens in interphase
the cell grows and DNA is replicated
35
what are the 3 phases of interphase
H1, S, G2
36
What happens in the mitotic phase
duplicated chromosomes are aligned, separated and move to opposite pole of the cell and divided
37
what is karyokinesis
the first portion of the mitotic phase
38
what are the phases of karyokinesis
prophase,
prometaphase
metaphase
anaphase
telophase
39
what is cytokinesis
the sctond portion of the mitotic phase where physical separation happens
40
outcome of meiosis
4 haploid cells
41
outcome of mitosis
2 diploid cells
42
What is the nucleolus
area in the nucleus where rRNA biosynthesis occurs and where assembly of ribosomes begin
43
What are 80s romosomes composed of
40s subunit and a 60s subunit
44
which ribosomes are 80s
non organelle- associated ribosomes in eukaryotic cells
45
where are free ribosomes found
in the cytoplasm
45
46
what do free ribosomes do
synthesize water soluble proteins
47
where are membrane bound ribosomes found
attached to the rough endoplasmic reticulum
48
what do membrane bound ribosomes do
make proteins for insertion into the cell membrane or proteins for export from the cell
49
what is the endomembrane system
series of membrane tubules, sacs and flattened disks that synthesize cell components and move materials within the cell
50
what organelle make up the endomembrane system
endoplasmic reticulum
Golgi apparatus
lysosomes
vesicles
51
what is the endoplasmic reticulum
interconnected array of tubules and cistern in a single lipid bilayer
52
what are cisternae
flattened sacs
53
water lumen
the spaces inside of the cisternae
54
described the rough endoplasmic reticulum
studied wit ribosomes bound on the cytoplasmic side of the membrane
55
what do the ribosomes in RER make
proteins destined for the plasma membrane
56
what are transport vesicles
small sacs of RER contain ing new proteins that bud off and move to Golgi apparatus or plasma membrane or out of cell or other membrane
57
what are transport vesicles composed of
single lipid bilayer membranous spheres with hollow interiors
58
why is smooth endoplasmic reticulum smooth
it does not contain ribosomes
59
what does smooth endoplasmic reticulum do
biosynthesis of lipids, carb metabolism and detoxification of compounds in cell
60
what is the Golgi apparatus composed of
a series of membranous disks called dictyosomes, each having a single lipid bilayer, that are stacked together
61
what does the Golgi apparatus do
enzymes in it modify lipids from the ER, adding carbs to them, producing glycolipids, glycoproteins or proteoglycans
62
what are glycolipids and glycoproteins used for
inserted into the plasma membrane for signal recognition by other cells or infectious particles or cell surface receptors
63
What is exocytosis
the process where secretory vesicles release their contents to the cells interior
64
what do lysosomes contain
digestive enzymes
65
what do lysosomes do
break down food, damaged organelles or cellular debris, microorganisms or immune complexes
66
what are peroxisomes
membrane bound organelles that are not part of of the endomembrane sustem
67
what do peroxisomes do
produce hydrogen peroxide , degrade hydrogen peroxide and lipid biosynthesis
68
what are glyoxysomes
modified peroxisomes of yeasts and plant cells
69
what do glyoxysomes do
metabolic functions such as produce sugar molecules
70
what are glycosomes
modified peroxisomes made by certain trypanosomes, the pathogenic protozoans
71
What is the cytoskeleton composed of
microfilaments, intermediate filaments and microtubules
72
What are microfilaments composed of
two intertwined strands of actin composed of actin monomers forming filamentous cables
73
what do actin filaments do
work with motor proteins like myosin to effect muscle contraction in animals or amoeboid movement of some eukaryotic microbes
74
what are the forms of actin in ameboid organisms
a stiffer polymerized gel form and a fluid unpolymerized soluble form
75
what does actin in the gel form do
creates stability in the ectoplasm
76
what are pseudopodia
temporary extensions of the cytoplasmic membrane
77
how are pseudopodia produced
through forward flow of soluble actin filaments into the pseudopodia followed by gel-sol cycling of actin filaments resulting in motility
78
other than movement what do microfilaments do
cytoplasmic streaming
cleavage furrow formation
muscle movement
79
what are intermediate filaments
cytoskeletal filaments that act as cables within the cell
80
why are they called intermediate filaments
they are thicker than actin but thinner than microtubules
81
what are intermediate filaments composed of
several strands of polymerized subunits that are made of monomers
82
other functions of intermediate filaments
maintain position of the nucleus, form the nuclear lamina, anchor cells together in animal tissues
83
What are microtubules composed of
tubular dimers
84
what do microtubules do
form hollow tubes that are used as girders within the cytoskeleton,
85
what does endosymbiotic theory state
mitochondria originally arose through and endosymbiotic event in which bacterium capable of aerobic cellular respiration was taken up by phagocytosis into a host and remains as a vital component.
86
what are mitochondria composed of
two lipid membrane
87
what does the outermembrane of mitochondria do
it is a remnant of the original hosts cell membrane structure
88
what does the inner mitochondrial membrane come from
derived from the bacterial plasma bembrane
89
what is the mitochondrial matrix
location of metabolic enzymes, contains mitochondrial dna and 70s ribosomes ,
90
what cells contain chloroplasts
plant cells and algae
91
what are chloroplasts
organelles in which photosynthesis occurs
92
what are the membranes of chloroplasts
outer
inner
thylakoid
93
where is the chloroplast stroma
between the inner and outer membrane
94
what is the stroma
a gel-like fluid that makes up much of a chloroplasts volume and where the thylakoid system floats
95
what is the thylakoid system
a dynamic collection of folded membrane sacks where chlorophyll is found and photosynthesis occurs
96
what organelles are similar to mitochondria
hydrogenosomes
kinetoplasts
97
what do hydrogenosomes do
serve as the location of anaerobic hydrogen production , lack their own dna and ribosomes
98
what are kinetoplasts
a variation of mitochondria in some eukaryotic pathogens, there is a long branched mitochondrion where kinetoplast dna is found in one pole of the cell
99
how is the plasma membrane in eukaryotic cells different than prokaryotes
it contains sterols such as cholesterol that alter membrane fluidity, contain some specialized lipids including sphingolipids
100
what is endocytosis
uptake of matter through plasma membrane invagination and vacuole formation
101
what happens in phagocytosis
particles or other cells are enclosed in a pocket within the membrane which pieces off from the membrane to form a vacuole that completey surrounds the particle
102
what happens in pinocytosis
small dissolved materials and liquids are taken into the cell through small vesicles
103
what is receptor mediated endocytosis
endocytosis that is initiated by specific molecules called ligands when they bind to cel surface receptors on the embrane (how hormones, viruses and bacteria enter cells)
104
What is exocytosis
process where secretory vesicles release their contents to the cell exterior
105
What does the extracellular matrix help with
helps maintain shape and structural stability of cells without a cell wall.
106
how does the extra cellular matrix work
secretes a stick mass of carbs and proteins in between adjacent cells
107
how is eukaryotic flagella different than prokaryptic
it is flexible like a whip and has nine parallel pairs of microtubules surrounding a central pair of microtubules
108
what causes eukaryotic flagellum to bend
dynein motor proteins
109
