Unit 2 Flashcards
Cell Structure and Function
1
Q
resolution
A
how clear the image on the microscope is
2
Q
scanning electron microscope
A
- scanning probe ascends an electron, it bounces off, and scanner tells where it bounced off
- only tells details about the surface of substance
- kills organism
3
Q
tunneling electron microscope
A
- shoots electrons right through surface and checks how to looks on the other side
- can see all internal mechanism
- kills organism
4
Q
cell fractionation
A
breaking up of particles to be put into a centrifuge, which spins and separates the fractions based off of size (mass)
5
Q
TYPES OF PROTEINS WITHIN A CELL’S MEMBRANE
A
6
Q
integral protein
A
within membrane
7
Q
transmembrane protein
A
across membrane
8
Q
transport protein
A
- a type of integral transmembrane protein
-create a channel for others to get in using carriers (larger organisms)
- used by ions and hydrophilic/polar molecules
- ex. aquaporins are channel proteins that let water through
9
Q
peripheral protein
A
outside of but connected to membrane
10
Q
unsaturated fatty acids within the plasma membrane
A
- the “kinks” in the hydrophobic parts of the phospholipid
- keep lipids from getting too close to each other
- make membrane less stable and more fluid
11
Q
cholesterol within animal cell membranes
A
- pulls/pushes phospholipids back together/apart so that they don’t push too far apart/together
- at low temps, lipids get closer; ___ pushes them apart
- nonpolar
12
Q
only small, _____ molecules are able to easily pass through the plasma membrane
A
hydrophobic/nonpolar
- ex. hydrocarbons, CO2, O2, etc.)
13
Q
passive transport
A
- small things get in through diffusion
- the natural movement of substances from high to low concentrations
14
Q
osmosis
A
- flow of water from areas of low solute concentration to areas of high solute concentration
- passive transport
15
Q
facilitated diffusion
A
- the use of a channel to move across a membrane
- process by which ions and hydrophilic/polar substances diffuse across the cell membrane
16
Q
hypertonic solution
A
- surrounding solution has higher concentration than the cell, so osmosis takes place, dehydrating it
- ex. cell becomes a raisin
- cell loses water to its surroundings
17
Q
hypotonic solution
A
- surrounding solution has lower concentration than the cell, so osmosis takes place, bloating it
- water enters cell faster than it leaves
18
Q
isotonic solution
A
- surrounding solution has the same concentration as the cell, so osmosis does not take place
- no net movement of water across the cell membrane
19
Q
water moves from a ____ solution to a ____ solution
A
hypotonic; hypertonic
20
Q
active transport
A
- when energy (ATP) must be used in order to bring something into a cell using a carrier protein
- movement of molecules against their gradient (low to high concentration)
21
Q
sodium-potassium pump
A
- active transport
- sodium out, potassium in
- necessary for proper nerve transmission and is a major energy consumer
22
Q
membrane potential
A
- difference in charge across a membrane expressed in voltage
- the inside of a cell is negatively charged compared to outside
- opposites attract, which drives diffusion across membrane
23
Q
voltage gradient
A
- across membrane
- attracts positively charged ions and repels negatively charged ions
24
Q
chemical force
A
ion’s concentration gradient
25
electrochemical gradient
both chemical force and voltage gradient acting on an ion
26
cotransport
where an ATP pump that transports a specific solute indirectly drives the active transport of other substances
27
bulk transport across the plasma membrane occurs by ______ and _____
exocytosis; endocytosis
28
exocytosis
vesicles from the cell’s interior fuse with the cell membrane, expelling their contents
29
endocytosis
cell forms new vesicles to take in macromolecules
30
CELL ORGANELLES
31
nuclear pores
allow communication between the outside of the cell and the nucleus
32
nucleolus
- quantum DNA that creates ribosomes
- nonmembranous structure
33
nucleoplasm
the inside of the nucleus
34
nuclear envelope
- “skin” of the nucleus that has pores
- double membrane (two phospholipid bilayers)
- continuous with endoplasmic reticulum
35
chromatin
- between nucleolus and nuclear envelope
- material consisting of DNA and proteins
- the cell’s genetic info
- visible in a dividing cell as individual condensed chromosomes
36
rough endoplasmic reticulum (ER)
- network of membranous sacs and tubes
- active in membrane synthesis and other synthetic and other metabolic process
- ex. detoxifying toxins
- internal area called cisternal space
- covered in ribosomes
37
smooth endoplasmic reticulum (ER)
does the exact same thing as rough, just not covered in ribosomes
38
cilium
push liquid around like boat oars
39
ribosomes
responsible for protein synthesis
40
free ribosomes
float in the cytosol and generally produce proteins that are used within the cell
41
bound ribosomes
are attached to the rough ER and make proteins destined for export from the cell
42
lysosome
digest/break macromolecules down by hydrolyzing (with H2O) in its acidic environment
43
centriole
play a role in cell division
44
centrosome =
two centrioles
45
peroxisome
- filled with enzymes that replicate division, but does not contain its own genomes
- has many roles
- ex. detoxifying alcohol
46
golgi apparatus
- active in synthesis, modification, sorting, and secretion of cell products
- packages and sends things like protein to other parts of the cell
47
secretory vesicles
package and send vesicles
48
mitochondria
generates all of the ATP/energy and CO2 a cell may need
- two phospholipid bilayers
- folds in inner membrane called cristae are where cellular respiration take place
- folds increase surface area, enhancing productivity
- area within inner membrane called the mitochondrial matrix
49
chloroplast
- photosynthetic organelle
- converts sunlight to chemical energy
- bounded by two phospholipid bilayers
50
thylakoids
membrane-bound compartments within a chloroplast
51
stroma
- fluid within the chloroplast
- contains DNA and ribosomes
52
endosymbiotic theory
mitochondria and chloroplast descended from prokaryotic cells once engulfed by ancestors of eukaryotic cells, so they have their own ribosomes and DNA
53
cytoskeleton
network of protein filaments (microfilaments, intermediate filaments, and microtubules) in the cytoplasm that provides structure and support
54
microtubules
- largest fibers
- separates chromosomes during mitosis and meiosis
- structural components of cilia and flagella
55
intermediate filaments
important in maintaining shape of the cell and fixing the position of certain organelles
56
microfilaments
- composed of the protein actin
- smaller-scale support
57
microvilli
microscopic protrusions on cell membrane that increase surface area for diffusion and minimize any increase in volume
58
flagellum
hair-like appendages that help cells move
59
central vacuole
- prominent in older plants
- functions include storage, breakdown of waste products, hydrolysis of macromolecules
60
plasmodesmata
cytoplasmic channels through cell walls connect the cytoplasm’s of adjacent cells
61
cell wall
made of cellulose, other polysaccharides, and protein
62
only animal cells contain:
lysosome, microvilli, centrosome, and flagellum
63
only plant cells contain:
cell wall, central vacuole, chloroplast, and plasmodesmata
64
carbohydrates are crucial in _____
cell-cell recognition
65
prokaryotic cells
- found in the domains Bacteria and Archaea
- no membrane-bound organelles in cytosol or nucleus
- smaller than eukaryotic cells
- only one circular chromosome within nucleoid
- no true nucleus
66
eukaryotic cells
- found in the domain Eukarya
- ex. animals, plants, fungi, protists
- larger than prokaryotes
- contain linear chromosomes in membrane-enclosed nucleus
67
the surface area to volume ratio becomes less favorable as a cell ___ in size
increases
- as volume increases, surface area increases, and the SA/V ratio decreases, and becomes less favorable
- because cells acquire resources through the plasma membrane, cell size is limited
68
surface area formula of a sphere =
4πr²
69
volume formula of a sphere =
(4πr³)/3
70
the electron transport chain and ATP production are associated with protein in the inner membrane of the ____
mitochondria
