1.3 The Cell Flashcards
(97 cards)
1
Q
What is cell theory?
A
cells are the basic units of life (the basic living units of organization), all cells come from other cells, cells function in all organisms
2
Q
What German scientists established cell theory?
A
Schleidan, Virchow, and Schwann
3
Q
what is a light microscope?
A
a device that passes light through a thin sample of the cell and then through a magnifying lens to be seen by the human eye
4
Q
cells can be as big as?
A
1 millimeter
5
Q
organelles can be used for what?
A
- energy conversion
2. for synthesis of needed compounds
6
Q
cells MUST…?
A
take in necessary materials, as well as excrete or expel waste
7
Q
plasma membrane surrounds
A
all cells and contains specialized gates and pumps to allow materials to enter and exit the cell
8
Q
SA to Volume
A
as a cell grows, the ratio of surface area to volume changes
9
Q
Cells need to remain small
A
- as the volume decreases, the SA increases
2. larger SA allows for metabolic processes to occur much faster
10
Q
Two basic types of cells
A
prokaryotic and eukaryotic
11
Q
Prokaryotic cells
A
- smaller than eukaryotic cells
- DNA is not enclosed in nuclear membrane
- do not contain many of the membrane bound organelles
12
Q
prokaryotic cells DO contain
A
- plasma membranes
2. ribosomes
13
Q
ribosomes
A
- composed of ribonucleic acid (RNA)
- synthesize proteins
- are not surrounded by a membrane
14
Q
what do membranes provide a location for?
A
metabolic processed to occur
15
Q
prokaryotes LACK
A
organelles with membranes, so the plasma membrane is often folded inward to create numerous folds for metabolic processes to occur
16
Q
Prokaryotes:diagram
A
- capsule (outer most layer)
- cell wall (second layer)
- plasma membrane (inner most layer)
- flagellum (singular tail attached)
- nucleoid (DNA)
- pili (hairlike structures)
- plasmid (mini coiled structures)
- ribosomes- floating circles
- cytoplasm- fluid inside cell
17
Q
Botulism
A
a type of food poisoning that can lead to paralysis and sometimes death
18
Q
Clostridium Botulinum
A
can form a dormant, durable cell called an endospore which is released by the bacterium under adverse conditions
19
Q
what happens during the canning process for food?
A
food is heated to boiling for about 3-4 mins to kill any highly heat resistant endospores
20
Q
Plants, animals, and humans all possess what type of cells?
A
eukaryotic cells
21
Q
Eukaryotic cells are
A
- larger- 10-100 x larger than prokaryotic cells
- have a nuclear membrane
- contain many membrane bound organelles
22
Q
why are membranes important to a complex cell?
A
- form compartments w/i organelles where reactants are more likely to come into contact
- keep certain compounds away from one another
- form a work surface where many enzymes can come together to complete a complex reactions
23
Q
eukaryotic cell: diagram
A
- nucleus (central)
- nucleous (center/inside of nucleus)
- nuclear envelope- surrounds nucleus
- mitochondria- bean like organelles
- peroxisome- circular purple
- lysosomes- circular orange
- ribosomes (small dots attached to ER)
- cytoplasm (fluid inside cell)
- ER- Blue tubular system attached to nucleus
- Golgi Apparatus- flattend sacs to side of ER
24
Q
Nucleus
A
surrounded by a nuclear membrane (envelope)
25
Nucleus is the most prominent organelle and contains what?
DNA
26
DNA is composed of what?
sequences of nucleotides
27
chromosomes are the packaged form of?
DNA
28
what are genes?
portions of the chromosomes
29
Genes determine what?
what proteins are synthesized in ribosomes
30
Information from DNA is transferred to...
ribosomes by mrna (messenger RNA)
31
What is rRNA
ribosomal ribonucleic acid (found in the ribosomes)
32
rRna is synthesized where?
in a region of the nucleus called the nucleolus
33
what do ribosomes do?
assemble proteins
34
what do ribosomes contain?
ribosomal RNA plus enzymes that are necessary to form the peptide bonds between AA
35
Each type of cell produces a unique combination of
proteins
36
the unique sequence of DNA in a cell serves as a code which specifies
the order in which AA are assembled
37
what are ribosomes often located?
on the ER
38
What is the ER
Endoplasmic reticulum- tightly packed/flattened sac-like structures that form interconnected compartments w/i the cytoplasm
39
rough ER
When ribosomes are located on the ER (RER)
40
After proteins are assembled by the ribosomes what happens?
they are modified and transported by the ER
41
Smooth ER
1. has no attached ribosomes
| 2. responsible for the synthesis of lipids
42
Both types of ER possess what?
a large variety of enzymes which catalyze (speed up) chemical reactions
43
cytoplasm (cytosol)
included the fluid portion of the cell and all the organelles outside of the nucleus
44
what is the Golgi complex (apparatus) named for?
the scientist who discovered it
45
The Golgi complex
is an organelle made up of stack of many flattened discs called cisternae
46
golgi complex is connected however
most form separate compartments
47
what is the golgi complex responsible for?
1. receiving lipids and proteins synthesized by the ER,
2. altering their structures and shipping them to other parts of the cell
3. making lysosomes
48
As portions pinch off from the Golgi membrane forming enclosed sacs called vesicles,
they and their contents can be transported to other organelles within the cell or exported out of the cell through the cell membrane
49
This is accomplished through what?
fusion of the vesicles with the plasma membrane of the cell or other membrane-bound organelles
50
fusion can occur b/c all membranes w/i the cell are structured
similarly
51
digestive enzymes produced by the Golgi complex are called what?
lysosomes
52
lysosomes are digestive enzymes that break down
biomacromolecules
53
lysosomes can also fuse with other vesicles containing what?
harmful bacteria (which allows for bacteria to be degraded into its components
54
tay sachs
a genetic disease, when one of the normally present digestive enzymes inside lysosomes is lacking
55
in tay sachs the toxic lipid in the brain cells
cannot be broken down which results in lipid buildup causing intellectual disability and death
56
mitochondria
responsible for converting the chemical energy found in food into ATP
57
what does ATP stand for?
adenosine triphosphate
58
what is ATP
A high energy molecule that provides energy to the cell a process called aerobic cellular respiration
59
what happens during aerobic cellular respiration?
oxygen is required to break down food. Carbon dioxide, water, and atp are produced
60
each mitochondria of a cell is bound by
a double membrane
61
intermembrane space
the space between the inner and outer membranes
62
the inner mitochondrial membrane possess numerous folds that
increase the surface area, allowing chemical reactions and enzymes required to transfer the chemical energy in food into ATP
63
eukaryotic cells contain
a cytoskeleton
64
eukaryotic cells contain
a cytoskeleton
65
the cytoskeleton consists of a network
of protein fibers that provide structural support and movement w/i a cell
66
what are the two types of protein fibers that compose the cytoskeleton?
1. microtubules
| 2. microfilaments
67
what are hollow cylinders like a tube that are involved in the movement of chromosomes during cell division
microtubules
68
what are in the strucutre of cilia and flagella?
microtubulues
69
where do cilia and flagella project from?
the surface of some cells
70
what is usually a long, whip-like structure that propels or pulls a single celled organism through a watery medium?
flagellum
71
where else is flagellum also found?
sperm cells
72
what are shorter and found in greater number on a cell?
cilia
73
in humans, where are cililated cells found?
along the respiratory passageways for trapping and moving debris
74
what is the name of the anchoring regions for microtubules?
MTOC's (microtubule- organizing centers)
75
during cell division, microtubules grow outward
from the MTOC assisting in the movement of chromosomes into two new cells
76
centrioles
made up of nine sets of three attached tubules arranged to form a follow cylinder
77
inside the MTOC of animal cells how many centrioles are there usually?
two
78
Similar structures called basal bodies anchor
cilia and flagella.
79
Both centrioles and basal bodies play
a role in microtubule assembly.
80
what are microfilaments?
flexible, solid fibers made up of two intertwined polymer chains of actin molecules
81
actin fiber cannot contract, BUT they can generate movement by
rapidly assembling and disassembling
82
during cell division what happens?
a ring of actin, associated with another protein, myosin, causes the constriction of the cell to form two daughter cells.
83
In muscle cells, actin and myosin slide past one another, shortening the muscle fiber and causing
muscle contraction
84
most eukaryotic cells are surrounded by
a cell coat
85
what is a cell coat made up of ?
polysaccharide side chains (carb), which project out from the proteins (glycoproteins), and lipids (glycolipds), which comprise the cell membrane
86
what do these side chains allow cells to do?
recognize one another, make contact/adhere to one another (groups of cells that perform a common function are tissues)
87
many eukaryotic cells secrete?
extracellular matrix- which contains tough protein fibers called collagen
88
animal cells and humans cells DO NOT
possess a cell wall
89
most plans and bacteria DO
possess a cell wall
90
thick cell walls in plants contain
multiple layers of cellulose fibers
91
these layers provide
strength and support for the stem, roots, and leaves
92
in bacteria, cell walls do not contain cellulose but contain
peptidoglycan- a 3D mesh like structure coposed of sugars and AA
93
bacteria possessing a thick peptidoglycan absorb/retain a violet stain called
gram-positive
94
bacteria possessing a thin peptidoglycan absorb retain a pink/red stain called
gram-negative
95
cell walls act as protection
for bacteria
96
antibiotic penicillin interferes with
the cell wall structure of gram positive bacteria resulting in a fragile cell wall that cannot protect the cell
97
animals and humans DO NOT require cells walls as they are often equipped with some form of supportive and or protective
skeleton
