Chapter 6&7 word list Flashcards
1
Q
focus a beam of electrons onto the surface of a specimen, providing images that look 3D
A
Scanning electron microscope
2
Q
- visible light passes through a specimen and then through glass lenses, which magnify the image
- The minimum resolution of an ____ _____ is about 200 nanometers (nm), the site of a small bacterium
- can magnify effectively to about 1,000 times the size of the actual specimen
- Various techniques enhance control and enable cell components to be stained or labeled
- Most subcellular structures, or organelles, are too small to be resolved by a LM
A
Light Microscope
3
Q
Scientists use ____ to visualize cells too small to see with the naked eye
A
microscope
4
Q
focus a beam of electrons through a specimen
A
Transmission electron microscopes
5
Q
subcellular structures
A
organelle
6
Q
- takes cells apart and separates the major organelles from one another
- Ultracentrifuges fractionate cells into their component parts
- Enables scientists to determine the functions of organelles
A
Cell fractionation
7
Q
semifluid substance called the _____ (or cytoplasm)
A
Cytosol
8
Q
What are the basic features of ALL cells
A
- Plasma membrane
- Semi Fluid substance called the cytosol (or cytoplasm)
- Chromosomes (carry genes)
- Ribosomes (Make proteins)
9
Q
- Have no nucleus
- DNA is in an unbound region called the nucleoid
- lack membrane bound organelles
A
Prokaryotic Cells
10
Q
- DNA in a nucleus that is bounded by a membranous nuclear envelope
- have membrane bound organelles
- generally much larger
- The logistics of carrying out cellular metabolism sets limits on the size of cells
A
Eukaryotic cells
11
Q
- a selective barrier that allows sufficient passage of oxygen, nutrients, and waste to service the volume of the cell.
- general structure of a biological membrane is a double layer of phospholipids
A
Plasma membrane
12
Q
- genetic library of the cell
- contains most of the DNA in a eukaryotic cell
- Ribosomes use the information from the DNA to make proteins
- contains most of the cell’s genes and is usually the most conspicuous organelle
- the nuclear envelope encloses the ____, separating it from the cytoplasm
A
Nucleus
13
Q
carry genes
A
chromosomes
14
Q
non membranous organelle involved in production of ribosomes; a nucleus had one or more nucleoli
A
nucleolus
15
Q
-carry out protein synthesis in two locations:
-in the cytosol (free ribosome)
-on the outside of the endoplasmic reticulum(ER)
or the nuclear envelope (bound ribosomes)
-are particles made of ribosomal RNA and rRNA and protein
A
Ribosome
16
Q
-regulates protein traffic and performs metabolic functions in the cell
A
Endomembrane system
17
Q
What are the components of the endomembrane system
A
- Nuclear envelope
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
- Vacuoles
- Plasma membrane
These components are either continuous or connected via transfer by vesicles
18
Q
composed of DNA and associated proteins; it carries the cell’s genetic information.
A
Chromatin
19
Q
- membrane bound sacs with varied functions
- diverse maintenance compartment
- contains materials in transport of the cell
A
Vesicles and Vacuoles (larger versions of vesicles)
20
Q
- accounts for more than half of the total membrane in many eukaryotic cells
- membrane is continuous with the nuclear envelope
A
Endoplasmic reticulum
21
Q
- biosynthetic factory
- ribosomes studding its surface
- has bound ribosomes
- Produces proteins and membranes, which are distributed by transport vesicles
- membrane factory for the cell
A
Rough ER
22
Q
- biosynthetic factory
- synthesizes lipids
- metabolizes carbohydrates
- stores calcium
- detoxifies poison
A
Smooth ER
23
Q
-shipping and receiving center
-Consists of flattened membranous sacs called cisternae
Functions: Modifies products of the ER,
Manufactures certain macromolecules, sorts and packages materials into transport vesicles
A
Golgi Apparatus
24
Q
-digestive compartments
-membranous sac of hydrolytic enzymes (=”recycling center”)
-can hydrolyze proteins, fats, polysaccharides,
and nucleic acids
-use enzymes to recycle organelles and macromolecules, a process called autophagy
A
Lysosomes
25
formed by phagocytosis
Food Vacuoles
26
found in many freshwater protists, pump excess water out of cells
Contractile Vacuoles
27
found in many mature plant cells, hold organic compounds and water
Central Vacuoles(plant cells)
28
Chemical energy conversion
- in nearly all eukaryotic cells
- have a smooth outer membrane and an inner membrane folded into cristae (crinkled cristae)
- the inner membrane creates two compartments: intermembrane space and mitochondrial matrix (Mito Middle=Matrix)
- some metabolic steps of cellular respiration are catalyzed in the _____ matrix
- Cristae present a large surface area for enzymes that synthesize ATP
Mitochondria: Chemical energy conversion
29
present a large surface area for enzymes that synthesize ATP
Cristae
30
-member of a family of organelles called plastids
-contain the green pigment chlorophyll, as well as enzymes and other molecules that function in photosynthesis
-found in leaves and other green organs of plants and algae
structure includes: Thylakoids, membranous sacs
Stroma, the internal fluid
Chloroplast: Capture of light energy
31
membranous sacs
Thylakoid
32
internal fluid
Stroma
33
- specialized metabolic compartments bounded by a single membrane
- contain the enzyme catalase to convert the hydrogen peroxide to water
Peroxisome
34
a network of fibers that organizes structures and activities in the cell
- a network of fibers extending throughout the cytoplasm
- organizes the cell's structures and activities, anchoring many organelles
- composed of three types of molecular structures:
- Microtubules
- Microfilaments
- Intermediate filaments
Cytoskeleton: Support, motility, Regulation
35
helps to support the cell and maintain its shape
- interacts with motor proteins to produce motility
- inside the cell, vesicles can travel along the "monorails" provided by the _____
- may help regulate biochemical activities
Cytoskeleton: Support, Motility, Regulation
36
Protein Subunits: Tubulin, consisting of a tubulin and b tubulin
Functions:
-Shaping the cell
-Guiding movement of organelles
-Separating chromosomes during cell division
-control the beating of cilia and flagella, locomotor appendages of some cells
Microtubule
37
Protein subunits: Actin
Main functions: Maintenance of cell shape (tension-bearing elements)
-Changes in cell shape
-Muscle contraction
-Cytoplasmic streaming
-Cell motility
-Cell division (cleavage furrow formation)
Microfilaments (Actin Filaments)
38
Protein subunits: One of several different proteins of the keratin family; depending on cell type
Main functions: Maintenance of cell shape (tension-bearing elements)
-Anchorage of nucleus and certain other organelles
-Formation of nuclear lamina
Intermediate Filaments
39
"microtubule organizing center"
1) in many cells, microtubules grow out from a ____ near the nucleus
2) In Animal cells, the ____ has a pair of ____, each with nine pairs or triplets of microtubules arranged in a ring
1) centrosome
| 2) centrosome, centrioles
40
anchors the cilium or flagellum
Basal body
41
(cellular extensions) extend and contract through the reversible assembly and contraction of actin subunits into microfilaments
Pseudopodia
42
- a circular flow of cytoplasm within cells
- This streaming speeds distribution of materials within the cell
- In plant cells, actin-myosin interactions and sol-gel transformations drive _____
Cytoplasmic streaming
43
- extracellular structure that distinguishes plant from animal cells
- protects the plant cell, maintains its shape, and prevents excessive uptake of water
- Plant cell walls are made of cellulose fibers embedded in other polysaccharides and protein
cell wall
44
relatively thin and flexible
primary cell wall
45
thin layer between primary walls of adjacent cells
Middle Lamella
46
added between the plasma membrane and the primary cell wall
Secondary cell wall
47
```
made up of glycoprotiens and other macromolecules
functions:
support
adhesion
movement
regulation
```
Extracellular matrix
48
- channels that perforate plant cell walls
| - through ______ water and small solutes (and sometimes proteins and RNA) can pass from cell to cell
Plants: Plasmodesmata
49
membranes of neighboring cells are pressed together, preventing leakages of extracellular fluid
Tight junctions
50
(anchoring junctions) fasten cells together into strong sheets
Desmosomes
51
(communicating junctions) provide cytoplasmic channels between adjacent cells
Gap Junctions
52
allowing some substances to cross it more easily than others
Selective permeability (of plasma membrane)
53
states that a membrane is a fluid structure with a "mosaic" of various proteins embedded in it
Fluid Mosaic Model
54
- penetrate the hydrophobic core and often span the membrane
- ______ that span the membrane are called transmembrane proteins
Integral Proteins
55
Membrane carbohydrates may be covalently bonded to lipids
glycolipids
56
Membrane carbohydrates may be covalently bonded to proteins
glycoproteins
57
chanel proteins called ____facilitate the passage of water
aquaporins
58
the difference in concentration of a substance from one area to another
concentration gradient
59
diffusion of a substance across a membrane with no energy investment
Passive transport
60
uses energy to move solutes against their gradients
Active transport
61
the diffusion of water across a selectively permeable membrane
Osmosis
62
solute concentration is the same as that inside the cell; no net water movement across the plasma membrane
Isotonic solution
63
solute concentration is less than that inside the cell; cell gains water
Hypotonic solution
64
solute concentration is greater than that inside the cell; cell loses water
Hypertonic solution
65
control of water balance
osmoregulation
66
transport proteins speed movement of molecules across the plasma membrane
Facilitated diffusion
67
two combined forces, collectively called the _______, drive the diffusion of ions across a membrane
Electrochemical gradient
68
the main electrogenic pump of plants, fungi, and bacteria is a ______
proton pump
69
occurs when active transport of one solute indirectly drives transport of another solute
Cotransport
70
- transport vesicles migrate to the membrane, fuse with it, and release their contents
- many secretory cells use ____ to export their products
Exocytosis
71
- the cell takes in macromolecules by forming vesicles from the plasma membrane
- is a reversal of exocytosis, involving different proteins
Endocytosis
72
some membrane proteins from junctions between adjacent cells
adhesion proteins
73
serve as docking sites for proteins of the extracellular matrix or hormones
receptor proteins
74
from pumps that use ATP to actively transport solutes across the membrane
transport proteins
75
from channels that selectively allow the passage of certain ions or molecules
channel proteins
76
some proteins, such as glycoproteins, are exposed on the extracellular surface and play a role in cell recognition and adhesion
recognition and adhesion proteins
77
attached to the surface of some proteins are
carbohydrate side chains
78
______ molecules are also found in the _______ because they help stabilize membrane fluidity in animal cells
Cholesterol; phospholipid bilayer
79
in a prokaryotic cell, Dna is in an unbound region called the ______
nucleoid
80
where rRNA is made and ribsomes are assembled
nucleolus
81
what are the components of the endomembrane system
```
nuclear envelope
endoplasmic reticulum
Golgi apparatus
Lysosomes
vacuoles
plasma membrane
```
82
what are the basic features of all cells
plasma membrane
cytosol (or cytoplasm)
chromosomes
ribosomes
83
microtubule organizing center; produce microtubules, which pull the replicated chromosomes apart and move them to opposite ends of the cell
centrioles
84
Cell wall: Yes/no
| prokaryote, plant cell,Animal cell
Yes yes no
85
Plasma membrane: prokaryote, Plant cell, Animal cell (Yes/No)
Yes, Yes, Yes
86
Organelles (Yes/no) Prokaryote, Plant cell, Animal cell
No yes yes
87
Nucleus (Yes/no) Prokaryote, Plant cell, Animal cell
No yes yes
88
centrioles (Yes/no) Prokaryote, Plant cell, Animal cell
No no yes
89
Ribosomes (Yes/No) Prokaryote, Plant cell, Animal cell
Yes Yes Yes
90
the cell takes in solids ("cell eating" cell engulfs particle in a vacuole
Phagocytosis
91
____ and _____ are threadlike structures best known for their locomotive properties in single celled organisms
Cilia and Flagella
92
one way movement of fluids brought about by pressure
Bulk flow
93
diffusion of solutes across a selectively permeable membrane
Dialysis
94
can help lipid insoluble substances get in or out
Channel proteins
95
help usher the substances across the plasma membrane, but its going to need energy
Transport protein
96
"cellular drinking" cell creates vesicle around fluid
Pinocytosis
97
Binding of ligands to receptors triggers vesicle formation
Receptor mediated endocytosis
98
A membrane separating the vacuole from the surrounding cytoplasm in a plant cell
tonoplast
99
A motor proteins in cells which converts the chemical energy contained in ATP into the mechanical energy of movement
Dynein
100
a motor protein in cells which converts the chemical energy contained in ATP into the mechanical energy of movement
Dynein
101
a membrane separating a vacuole from the surrounding cytoplasm in a plant cell
tonoplast
102
forms microfilaments
actin
103
move materials between organelles or between organelles and the plasma membrane
transport vesicle
104
a complex of proteins and DNA
Chromatin
105
A protein that converts chemical energy in the form of ATP to mechanical energy
myosin
106
some metabolic steps of cellular respiration are catalyzed in the _______
mitochondrial matrix
