Organelles quick questions Flashcards
chapter 7
1
Q
Which cell functions in:
cell adhesion, recognition and
communication, and…
A
Plasma Membrane
2
Q
What are the 2 main components of plasma membrane?
A
Phospholipids molecules and Protein molecules (also cholesterol)
3
Q
How long is a DNA strand?
A
2 meters long
4
Q
Difference b/w chromatin and chromosomes?
A
Chromatin: loosely arranged DNA and protein
Chromosomes: tightly packed DNA
5
Q
How many chromosomes does a human have?
A
23 pairs = 46 chromosomes
6
Q
Which organelle ensures everything that enters/leaves the cell
A
Plasma membrane
7
Q
Why would we want to separate internal and external environments with plasma membranes?
A
To regulate movement in/out of cells
8
Q
Which part of a phospholipid is hydrophilic
A
the head
9
Q
A phospholipid is what kind of molecule?
A
it’s an amphipathic molecule
head = hydrophilic
tail = hydrophobic
10
Q
Is the cell membrane selectively permeable or completely permeable?
A
selectively permeable
11
Q
How do we call the region b/w the nucleus and the plasma membrane?
A
Cytoplasm
12
Q
The fluid substance within the membrane
A
Cytosol
13
Q
Which organelle is wrapped in “double membrane”
A
nucleus
14
Q
Is the nucleolus membrane-bound?
A
no
15
Q
What makes ribosomes?
A
nucleus
16
Q
Why does the nucleus have pores?
A
to permit exchange of materials b/w nucleus and cytoplasm
17
Q
How do we call the double membrane on the nucleus?
A
nuclear envelope
18
Q
Main function of Nucleus
A
Control center of the cell
19
Q
Which organelle is continuous with the nuclear
envelope
A
ER
20
Q
What does ER stand for?
A
Endoplasmic Reticulum
21
Q
Name the 2 kinds of ER
A
RER (Rough ER)
SER (Smooth ER)
22
Q
Does RER or SER have ribosomes?
A
RER has ribosomes
23
Q
Which ER produces proteins
A
RER
24
Q
Does RER or SER distribute proteins by transport vesicules?
A
RER
25
2 main functions of RER
Synthesis and transport of proteins +
Modification of proteins
26
What does SER synthesize?
Fats: lipids, phospholipids, steroids
27
Which ER detoxifies poison? RER or SER?
Smooth ER
28
Which ER metabolizes carbohydrates and stores some minerals?
SER
29
4 main functions of SER
- synthesize and transport lipids
- detox
- metabolize
- storage of calcium
30
What is one word you think of when talking of Golgi Apparatus
Warehouse
31
Which organelle has the functions of manufacturing, sorting, shipping center for cell products?
Golgi Apparatus
32
True or False: Golgi synthesizes carbohydrates
TRUE
33
Which organelle modifies the chemicals of molecules?
Golgi
34
What are the main functions of vesicles?
Store and transport chemicals throughout the cell
35
What organelle are called membrane-enclosed sacs
vesicles
36
How many types of vesicles are there?
2 types of vesicles:
Transport (ER)
Secretory (Golgi)
37
Nuclear envelope of the nucleus is connected to which organelle?
the rough ER
38
Why are lysosomes important?
they destroy specified suubstances
39
The lysosomes are known as what?
the cell's demolition crew
40
Lysosomes are like vesicles that contain what?
that contain digestive enzymes
41
The enzymes in the lysosomes are only active within which membrane?
within the acidic membrane
42
There are 2 types of lysosomes, name them and specify their function
Phagocytosis -> digests material OUTSIDE of cell
Autophagy-> digests organelles from INSIDE of cell
43
Which organelle detoxifies alcohol and other harmful compounds?
Peroxisomes
44
Main function of mitochondria
Powerhouse of the cell
44
Which organelle turns hydrogen peroxide into water? H2O2 --> H2O
Peroxisomes
45
What do the mitochondria convert?
they convert food energy into energy cell use
46
The mitochondria convert glucose into what?
ATP (Adenosine triphosphate)
47
How many layers do mitochondria have?
2 membranes composed of 2 phospholipid bilayer
48
Which organelle is thought to derive from bacteria-like endosymbionts?
Mitochondria
49
What is located within the nucleus?
the nucleolus
50
What is the mian function of a nucleolus?
production and assembly of ribosomes
51
Does the nucleolus have a membrane sperate from the rest of the nucleus?
NO, no membrane seperates the nucleolus
52
Main function of a ribosome
Protein synthesis
53
Where can you find ribosomes? (2)
- free-floating in cytoplasm
- attached to RER
53
What do the ribosomes attached to the RER do?
they make proteins that can be stored and released when needed
54
3 smaller organelles are part of the cytoskeleton, name them
microtubules, microfilaments and intermediate filaments
55
Main function of cytoskeleton
form and internal framework to support and give shape to cells
56
TRUE or FALSE:
Cytoskeleton can extend and/or contract (allows cells to change shape)
TRUE
very dynamic (can quickly be dismantled on one part of the cell)
57
Name the organelle: part of the cytoskeleton, thickest and hollow
Microtubules
58
2 main functions of microtubules
- support cell (rigidity)
- transport
59
What do microtubules act as?
railroad tracks (involved in the movement of organelles in cell (vesicle transport))
60
Is the centrosome a membranous organelle?
no, it's a non-membranous organelle
61
Centrosomes are made up of a pair of what?
pair of centrioles (at right angles to each other)
62
Which organelle that is part of the cytoskeleton moves chromosomes during cell division?
Centrosomes
63
Which organelle is a microtubule-organizing center?
centrosomes/centrioles
64
What are the organelles used for movement in the cell? (2)
Flagella and cilia
65
Relate each term with the correct organelle (Flagella vs Cilia):
long, short
numerous, few
Flagella -> long and few
Cilia -> short and numerous
66
Intermediate Filaments have which function in the cell?
maintenance of cell shape
67
Do Intermediate Filaments bin ATP and serve as tracks for transport?
NO
68
Microfilaments are strings of what? (2 chains)
actin
69
Where do you find actin?
in muscles
70
Microfilaments 2 main functions
- maintenance of cell shape
- movement of cell (contraction..)
71
What do we call the outer jelly-like matrix?
Extracellular matrix
72
4 main functions of the extracellular matrix
- holds cells together
- help regulate cell behavior
- cell signaling
- cell receptors
73
What is the extracellular matrix made of?
carbohydrates and fibrous proteins
74
Other eukaryotic cells (protists) have this other organelle, name it
the contractile vacuole
75
Choose the correct term ( function of Contractile Vacuole)
it exports excess water collected from (inside or outside) the cell
it exports excess water collected from INSIDE the cell
76
Why does the contractile vacuole export excess water?
to maintain cytoplasmic concentration of chemicals
77
Other Eukaryotic cells (plant cells)
they have 3 things animal cells don't have, name them:
- cell wall
- chloroplast
- central vacuole
78
What does the plant cell lack that animal cells have?
centrioles
79
Cell wall in plant cells are made of what?
cellulose
80
TRUE OR FALSE:
Cellulose in plant cell wall provides support in the cell and ultimately the plant
TRUE
81
TRUE OR FALSE:
Cellulose is soft and squishy
FALSE:
Cellulose is hard and rigid
82
2 main function of the cell wall
- rigidity
- helps prevent water loss
83
How do we call the pores in the cell wall?
Plasmodesmata
84
Through the pores of the cell wall (plasmodesmata), what does it connect?
the cytoplasm of 2 cells
85
What do the pores permit?
they permit the movement of fluids between cells (water and small solutes can pass freely from cell to cell)
86
Organelle in plant cells that take up 90% of plant cell volume:
Central vacuole
87
The main function of the central vacuole in plant cells (other than supports cells and ultimately the plant) (3)
- storing various compounds (to help defend the plant against herbivores)
- disposing of metabolic wastes
88
the central vacuole helps maintain what?
turgor
89
What is turgor in plant cells?
Pressure exerted by fluid in a cell that presses the cell membrane against the cell wall
90
What is a tonoplast?
a membrane
91
Main function of chloroplast
Site of photosynthesis
92
Where do we find chloroplasts?
in green parts of the plant
93
We compare chloroplast to which other organelle?
the mitochondria
94
What are the 2 main similarities b/w the mitochondria and chloroplasts?
both convert energy AND both have DNA and ribosomes
95
Energy-converting organelles (mitochondria and chloroplasts) name the conversion of energy
MITO: food --> ATP
CHLORO: solar energy --> FOOD (chemical energy through photosynthesis)
96
To make ATP, the mitochondria require what?
O2
97
To create glucose, chloroplasts use what?
CO2 and solar energy
98
Are mitochondria and chloroplasts double membrane organelles?
YES
99
What does it mean that the mitochondria and chloroplasts each have their own DNA and proteins?
it means they can make their own ribosomes and they can SELF-REPLICATE
100
What provides the cell's special characteristics?
the specific components of a given cell
101
What could be an example of specific components for differential gene expression?
2 cells can obtain different SUBSETS of gene products (proteins)
102
Do all cells have the same genes? what are the exceptions?
TRUE, but each cell only expresses the genes that it requires (won't express other tissue-specific genes)
103
Write the correct percentage:
A typical human cell probably expresses about __% of its genes at any given time
20%
104
TRUE or FALSE: they contain the EXACT same genes
but only neurons can express the nerve genes
only epithelial cells can express epithelial genes
TRUE TRUE TRUE
105
TRUE OR FALSE:
Viruses are host-specific
TRUE
b/c they have specific receptors where they bind (for ex. HIV -/ immune cells)
106
What does a virus do once inside the cell
the viral nucleic acids can take over the cell and direct it to make more viruses
107
Once a virus binds to a receptor it can do 2 things:
+ What happens in either case?
- enters the cell
OR
- injects its nucleic acid into the cell
=> The protein coat is released and the viral nucleic acid will replicate (using the machinery of the host cell)
108
Viral genes can take command of the host's metabolic pathways and direct it to make what?
to make new copies of the original virus
109
Once what happens that the virus is assembled and then released?
once the viral nucleic acid and protein coat are made
110
TRUE OR FALSE:
The virus doesn't kill its host cell
FALSE
the virus usually kills its host cell
111
We use antibiotics for what?
for bacteria (no ribosomes or DNA to replicate)
112
We use Vaccines for what?
viruses, bacteria, etc.
