Chapter Four: Origin and General Features of Cells Flashcards
(173 cards)
1
Q
The Cell Theory (3)
A
- Cells are the fundamental unit of life
- All organisms are composed of Cells
- All cells come from preexisting cells
2
Q
As cells increase in volume the surface area also increases, but at a ___________ rate.
A
lesser
3
Q
The cell’s ____________ determines its metabolic activity.
A
volume
4
Q
The cell’s ________ ________ determines the rate of transport into and out of the cell.
A
surface area
5
Q
As a cell grows, its ____________ ____________ increases, but at a rate faster than the increase in surface area.
A
Metabolic Activity
6
Q
Magnification makes something ___________
A
larger
7
Q
resolution makes something _____________
A
clearer
8
Q
Microscopes increase both the ____________ and _____________ of objects
A
magnification and resolution
9
Q
The ability to see two objects as two instead of one object
A
Resolution
10
Q
What kind of microscope uses light passing through the sample to observe objects?
A
Light Microscope
11
Q
200 nm (2 x 10^-4 mm) is the resolving power for what microscope?
A
Light Microscope
12
Q
What kind of microscope uses an electron beam passing through the sample to view objects?
A
Transmission Electron Microscope
13
Q
What kind of microscope’s resolving power is 0.2 nm (2 x 10^-7 mm)
A
Transmission Electron Microscope
14
Q
Cells must be killed and stained with heavy metals to block the electron beam in what microscope?
A
Transmission Electron Microscope
15
Q
What microscope coats the surface of the sample with heavy metal stains, then uses an electron beam to scan the surface and obtain more of a 3D view of the surface?
A
Scanning Electron Microscope
16
Q
What microscope’s resolution is about 10nm?
A
Scanning Electron Microscope
17
Q
Life requires an interaction between what three things?
A
- DNA
- RNA
- Protein
18
Q
What are the four proposed stages of the origin of life?
A
- production of nucleotides and amino acids
- polymerization of these monomers into polymers
- enclosing the polymers in membranes
- membrane-bound photocells acquire cellular properties
19
Q
What did Oparin and Haldane propose in the 1920s?
A
Nucleotides and Amino Acids were produced spontaneously under early earth conditions
20
Q
Oparin and Haldane suggested that monomers were produced and accumulated in what is called a “____________ __________”
A
Primordial Soup
21
Q
In the 1950s, geologists suggested the early Earth’s atmosphere was a reducing one consisting of what three molecules?
A
- Water Vapor
- Hydrogen
- Ammonia
22
Q
It is important there was no free ___________, since that would destroy any organic molecules produced.
A
Oxygen
23
Q
What did Stanley Miller produce in 1953?
A
An enclosed system which circulated reducing gases in which a spark produced an energy source and produced simple organic molecules
24
Q
Those who have suggested that Miller is wrong says that the atmosphere is composed mostly of what 5 molecules?
A
- Carbon Monoxide
- Carbon Dioxide
- Nitrogen
- Sulfur Dioxide
- Water
25
The mixture of the five atmospheric molecules gives less diversity and __________ yields of amino acids.
lower
26
UV light would destroy _____________ and _____________, preventing their accumulation in an early atmosphere.
Methane and Ammonia
27
Other scientists suggest that _____________ could have brought sufficient amounts of organic molecules to Earth.
Meteorites
28
Other scientists suggest molecules would form at the edge of ________ ______ _______ where super-heated gasses are vented.
Deep Sea Vents
29
Chemically the ________ Phosphodiester linkage is preferred over the _________ linkage.
5 prime - 2 prime
5 prime - 3 prime
30
Has Ribose been proven possible under any of the conditions expected in early Earth system?
No
31
Where does Steve Benner propose RNA is formed and how it comes to Earth?
It was formed on Mars and came to Earth on meteorites
32
Monomers attach together to form…
Polymers
33
Hydrolysis would compete with __________________ reactions (polymerization)
Condensation
34
Water promotes ________________ removal
depurination/base
35
It is unlikely that ______________ would occur in aqueous environments, but rather on solid surfaces
Polymerization
36
Many ________ bind Nucleotides and Amino Acids.
clays
37
__________ can position Nucleotides to connect the phosphate of one with the Ribose of another.
Cations
38
Cations favor the use of _________ over T and C
A and G
39
Cations favor _________ over A and G
Inosine
40
Clays promote ____________ in presence of water
decomposition
41
A normal peptide bond requires a ___________ to insure correct bond formation
Ribosome
42
Side chain of _______ ________ can bond to the side chain, amino or carboxyl of another
amino acids
43
Majority of bonds formed abiotically are NOT _________ _________.
Peptide Bonds
44
________________ _________ or Phosphate group of one can attach to any of the four hydroxyl groups of Ribose
Nitrogenous Base
45
If polymers were formed, they would have to be enclosed in _____________ and develop the ability to reproduce
membranes
46
Organic molecules would need to be __________ from the external environment.
separated
47
They would eventually need _________ __________ to create new polymers and harness energy
enzymatic functions
48
If phospholipids are dissolved in water, they form __________
Liposomes
49
If Liposomes form near ______ it can be incorporated into the Liposome.
RNA
50
RNA that isn’t incorporated into the Liposome requires ___________ ______________.
protein transporters
51
_____% of all proteins function in membranes
30
52
Are membranes made from scratch?
No
53
All membranes come from ___________ _____________.
preexisting membranes
54
Favored models of the production of cells propose an “__________ world”
RNA
55
According to favored models, RNA can do what 3 things?
1. function as genetic material
2. function as enzymes
3. reproduce
56
the minimum complexity needed to maintain the processes in the simplest cells is defined as…..
Irreducible Complexity
57
Cells need a minimum of _______ genes
493
58
DNA replication in simplest prokaryotes requires _____ enzymes and _______ polypeptides
14 and 25
59
DNA cannot replicate without ________
proteins
60
proteins cannot be produced without _______ and __________
DNA and RNA
61
What are the two domains of prokaryotic cells?
Eubacteria and Archaebacteria
62
Name the three characteristics of Prokaryotic Cells:
- lack membrane-bound organelles
- are relatively simple in structure
- are generally smaller than eukaryotic cells
63
Name the structure and function of the PLASMA MEMBRANE
single membrane
regulate transport
64
Name the structure and function of a NUCLEOID
Aqueous
Heredity
65
Name the structure and function of the CYTOPLASM
Aqueous
Biochemical Reactions
66
Name the structure and function of RIBOSOMES
Solid - RNA and Proteins
Protein Synthesis
67
Name the structure and function of the CELL WALL
Peptidoglycan Membrane
Protection/Support
68
Name the structure and function of a CAPSULE
Polysaccharides
Protection/Hydration
69
Name the structure and function of the FLAGELLA
Solid - Proteins
Movement
70
Name the four domains of Eukaryotic Cells
Kingdoms Protista
Plantae
Fungi
Animalia
71
What are the three characteristics of Eukaryotic Cells?
1. possess membrane-bound organelles
2. are complex in structure with many organelles
3. are larger in size
72
The Cytoplasm is an aqueous mixture of a wide variety of __________
proteins
73
The three fibers within the cytoskeleton are constructed from _______ __________
protein monomers
74
Large, long hollow tubes of Tubulin contributing to the Cytoskeleton
Microtubules
75
_________ and ___________ _________ control microtubule growth from one point to another
Centrioles and Basal Bodies
76
Microtubules form cellular “_________” along which vesicles and chromosomes move using molecular “__________” (Kinesin)
roads
motors
77
Motor proteins are attached to either _______ (cargo) or other cytoskeleton elements
vesicles
78
Motor proteins have areas that can bind and split _____, and others that move.
ATP
79
Motor proteins either move vesicles containing various molecules, or other parts of cytoskeleton to create _________ _________ or _____________.
shape changes
movements
80
Microtubules form ________ and _________ for cellular locomotion
Cilia and Flagella
81
Microtubules form the _______ ________ for moving chromosomes during cell division
mitotic spindle
82
What is the structure of Intermediate Filaments
Thin rods of Keratin
83
________ ____________ are stable elements of the cytoskeleton that are not constantly growing and shrinking
Intermediate Filaments
84
What is the function of Intermediate Filaments?
Maintain cellular shape and provide mechanical strength to cells
85
Intermediate Filaments line the inside of the _______ _______ to anchor __________ _______
Nuclear Membrane
Nuclear Pores
86
What is the structure of microfilaments?
Thin rods of Actin proteins
87
Microfilaments can exist as ______ ___________, in bundles or in networks
single filaments
88
What are the five functions of Microfilaments?
1. Cellular movements
2. Cytoplasmic division
3. Support Plasma Membrane
4. Anchor Proteins
5. Provide Strength and Shape to Cell
89
Name the structure and function of the NUCLEUS
Double Membrane
Stores DNA
90
Nuclear Pores _______ __________ between the Nucleus and the Cytoplasm
regulate transport
91
The Nuclear pores are surrounded by a complex of ___ large protein granules
8
92
Proteins targeted for the Nucleus have a short peptide ________ __________ __________
Nuclear Localization Signal
93
Nucleolus: consists of the gene(s) which codes for _____________ ______
Ribosomal RNA
94
rRNAs are needed for ______________ construction
Ribosome
95
The outer of the two Nuclear Membranes is in places continuous with the _________ ___________
Endoplasmic Reticulum
96
What six things are within the Endomembrane System?
1. Nuclear Envelope
2. Ensoplasmic Reticulum
3. Golgi Apparatus
4. Lysosomes
5. Plasma Membrane
6. Vesicles
97
What is the structure of the Endoplasmic Reticulum?
Single membrane surrounding a central lumen
consists of tubes and flattened sacs
98
What percent of the cell’s total volume does the ER compose?
10%
99
It’s membranes, because of the many folds, is many times __________ than the Plasma Membrane
greater
100
The Rough ER is studded with…
Ribosomes
101
Ribosomes synthesize _______ which are transported into the lumen of the _________, segregating them from the Cytoplasm
proteins
ER
102
The proteins in the ER can be ___________ _____________ to alter their functions
chemically modified
103
Proteins are also “tagged” with a short peptide signal to mark them for _________ to various organelles by vesicles
delivery
104
Some of these proteins have an oligosaccharides chain attached and form ______________
Glycoproteins
105
Rough ER _____________ glycoproteins, membrane-bound proteins, and proteins destined for various organelles
Synthesizes
106
In the Rough ER, ribosomes synthesize proteins which are transported into the lumen of the ER, segregating them from the ______________
Cytoplasm
107
What organelle lacks ribosomes and is more tubular than flattened sacs; continuous with sections of the Rough ER?
Smooth ER
108
In the Smooth ER, detoxification of various poisons taken into the body by modifying them to be more ___________ and easier to excrete from the cell
Polar
109
The Smooth ER contains ______________ needed for Glycogen and Calcium metabolism
Enzymes
110
The Smooth ER synthesizes ____________ for membranes and other lipids including steroid hormones
Phospholipids
111
What organelle is made of flattened sacs and has a single membrane surrounding central lumen?
Golgi Apparatus
112
The Golgi Apparatus adds or modifies ____________ portions of Glycoproteins
Carbohydrate
113
Proteolysis occurs in what organelle?
Golgi Apparatus
114
proteases cut proteins into smaller, functional proteins
EX: proinsulin --> insulin
Proteolysis
115
What organelle concentrates, packages and sorts proteins before being transported to cellular destinations?
Golgi Apparatus
116
transport proteins from the ER to the cis to medial to the trans regions of the Golgi Apparatus
Vesicles
117
Large vesicles containing digestive enzymes (Glycoproteins), surrounded by a single membrane
Lysosome
118
What organelle digests via Hydrolytic Reactions?
Lysosome
119
Formed by vesicles containing Hydrolytic Enzymes forming form the Golgi
Primary Lysosomes
120
Formed by the fusion of a primary lysosome and a food vacuole (phagosome)
Secondary Lysosome
121
Large and small solid subunits composed of 1-3 rRNAs and 20-30 Proteins
Ribosomes
122
Involved in protein synthesis and is free in the Cytoplasm, attached to the ER, or inside Mitochondria and Chloroplasts
Ribosomes
123
Similar to large vesicles, they store food or waste materials and maintain turgor pressure
Vacuoles
124
Freshwater protists use them to excrete excess water. Water diffuses in, then this vacuole contacts, forcing water out of a pore
Contractile Vacuoles
125
Vesicle-like and contains enzymes for specific functions
Microbodies
126
These organelles contain catalase that is used to degrade Hydrogen Peroxide (a byproduct in many reactions). They also synthesize as vesicles from the ER.
Peroxisomes
127
This is a byproduct of many reactions, but in high levels can be toxic. It is degraded by Peroxisomes.
Hydrogen Peroxide
128
These organelles are like peroxisomes, and contain enzymes for specific reactions, found primarily in plant seeds, and convert stored lipids into carbohydrates for growth
Glyoxysomes
129
Surrounds the cell and divides it from the external environment
Plasma Membrane
130
What organelle facilitates membrane transport, facilitates cell signaling, facilitates cell adhesion, and is part of the endomembrane system?
Plasma Membrane
131
What fills the role of facilitating membrane transport?
Protein transporters
132
What fills the role of facilitating cell signaling?
Hormones
133
What fills the role of facilitating cell adhesion?
Different types of proteins
134
This organelle produces and stores various carotenoid pigments producing red, yellow and orange colors in flowers and fruit
Chromoplasts
135
What type of organelles are both Mitochondria and Chloroplasts?
Semiautonomous Organelles
136
What organelle's responsibility is cellular respiration?
Mitochondria
137
What organelle's responsibility is photosynthesis?
Chloroplasts
138
What two organelles can divide independently of the cell due to containing their own DNA and Ribosomes?
Mitochondria and Chloroplasts
139
What organelle is double membraned and converts energy in organic molecules to ATP?
Mitochondria
140
Cellular respiration begins in the Cytoplasm with _________________
Glycolysis
141
After Glycolysis, cellular respiration continues in the Mitochondria with the _____________ __________ and Electron Transport
Krebs Cycle
142
What is the end product of Cellular Respiration?
ATP
143
A modified nucleotide with a high energy content
ATP
144
If the inner mitochondrial membrane has special pores for protons, the Electron Transport generates _________ instead of ATP
heat
145
These organelles are chloroplasts and have three membranes
Plastids
146
Chloroplasts contain the photosynthetic pigments, embedded within internal stacks of membranes called.....
Thylakoids
147
The fluid surrounding the Thylakoids is the ___________
Stroma
148
Only 10% of the Thylakoid Membrane is ______________
Phospholipids
149
These organelles store food (starch and fats)
Leucoplasts
150
This organelle is a thin mat of cellulose fibers that supports the cell. It limits the volumes of the cell to help maintain Turgor Pressure and forms a barrier to prevent infection by Fungi and Bacteria
Cell Wall
151
What is the starting point of the Endosymbiont Theory?
Prokaryotic cells - some had Aerobic Respiration and others had Photosynthesis
152
What is the Engulfment stage in Endosymbiont Theory?
Large Prokaryotic cells engulf smaller ones but do not digest them
153
According to Endosymbiont Theory, over time these engulfed cells become what two double membrane organelles?
Mitochondria and Chloroplasts
154
Interwoven mat of Collagen and a matrix of Glycoproteins (Proteoglycans)
Extracellular Matrix
155
Proteins that link other proteins together into a continuous unit and helps connect adjacent cells together are major roles of the....
Extracellular Matrix
156
In Eukaryotic cells, each organelle has its own set of ___________ which carry out most of the functions of that organelle
Proteins
157
Most proteins are synthesized on Ribosomes in the ___________
Cytoplasm
158
If proteins are not destined for an organelle, then they will stay in the _______________
Cytoplasm
159
Many proteins take the first step in sorting them to organelles as they are ____________
Translated
160
The first 12-20 amino acids in Cotranslational Sortingare ____________ and form an ER Sorting Signal
Non-polar
161
A special protein, ________________, finds and binds the signal (Hydrophobic amino acids)
Signal Recognition Protein (SRP)
162
SRP drags the Ribosome to the _________ and attaches to the SRP Receptor
ER
163
When SRP docks with the Receptor, the protein chain is threaded through the ______________________
Channel Protein
164
The protein that is threaded through the channel protein is then threaded through the ER so it will end up in the _____________ of the ER. The SRP is now finished and leaves
Lumen
165
After the proteins are translated, they are packaged into ___________ for transport to the destination organelle
Vesicles
166
The vesicles destined for an organelle have specific _________ embedded in the membrane to help concentrate the proteins being carried and to help the vesicle fuse with the proper target organelle
Proteins
167
Proteins that are destined for the Nucleus, Microbodies, Mitochondria and Chloroplast are synthesized on ______________ in the Cytoplasm are sorted after they are made
Ribosomes
168
The first 12-20 amino acids in post-translational sorting on these proteins are special sequences which act as a ______________ ___________
Sorting Signal
169
The Transit Sequence is bound and transported to a receptor protein on the outer _______________ membrane
Mitochondrial
170
______________ proteins keep the protein in an unfolded condition so it can be threaded through the channel protein more easily
Chaperone
171
The protein is threaded through a channel protein where it is delivered to the ____________ and its signal sequence is removed. The Chaperone protein detaches and assumes its active shape ti become active in the duties of the ___________________
Matrix
Mitochondria
172
___________ proteins are unique in that their signal or transit sequences are not removed
Nuclear
173
The position of the _________ keeps changing with each cell division and Nuclear proteins must be gathered and delivered to the new _____________
(same word in both blanks)
Nucleus
