Bio #1 Flashcards
1
Q
the human body contains ______ bacteria cells than eukaryotic cells
A
more
2
Q
endothelial vs. epithelial cells
A
Endothelial cells cover the inner surface of the blood vessel, while the epithelial cells cover the inner surface of the internal organs and the outer surface of the human body.
3
Q
protein synthesis occurs in the ______
A
rough ER and ribosomes
4
Q
proteins that will be excreted pathway:
A
rough ER-Smooth ER-Golgi
5
Q
original cell theory
A
o 1. All living things are composed of cells.
o 2. The cell is the basic functional unit of life
o 3. Cells arise from preexisting cells.
o (4.) NEW: Cells carry genetic information in the form of DNA. This genetic material is passed on from parent to daughter cell
6
Q
eukaryotic cells vs. prokaryotic cells
A
- Eukaryotic cells: nucleus enclosed in a membrane, can be unicellular or multicellular.
- Prokaryotic cells: no nucleus, always single-celled
7
Q
organelles
A
suspended in semifluid cytosol
8
Q
cytosol
A
the aqueous component of the cytoplasm of a cell, allows for diffusion of molecules throughout the cell
9
Q
nucleus
A
o Surrounded by the nuclear membrane or envelope (double membrane)
o Nuclear pores: in the nuclear membrane and allow selective two-way exchange of material between the cytoplasm and the nucleus.
o Nucleolus: where ribosomal RNA (rRNA) is synthesized. Darker spot on the nucleus.
10
Q
is the nuclear membrane double membrane?
A
yes
11
Q
nuclear pores
A
: in the nuclear membrane and allow selective two-way exchange of material between the cytoplasm and the nucleus.
12
Q
nucleolus
A
where ribosomal RNA (rRNA) is synthesized. Darker spot on the nucleus.
13
Q
mitochondria
A
power plants of the cell
o Contains an outer and inner membrane.
Outer membrane: serves as a barrier between the cytosol and the inner environment of the mitochondrion.
Inner membrane: organized into cristae, contains the molecules and enzymes of the electron transport chain.
o Intermembrane space: the space between the inner and outer membranes.
o Mitochondrial matrix: the space inside the inner membrane.
o Contain some of their own genes and replicate independently of the nucleus via binary fission.
Cytoplasmic or extranuclear inheritance: the transmission of genetic material independent of the nucleus.
o Also play a role in kick-starting apoptosis.
14
Q
outer membrane of mitochondria
A
serves as a barrier between the cytosol and the inner environment of the mitochondrion.
15
Q
inner membrane of mitochondria
A
organized into cristae, contains the molecules and enzymes of the electron transport chain.
16
Q
inter-membrane space of mitochondria
A
the space between the inner and outer membranes.
High concentration of protons
17
Q
mitochondrial matrix
A
the space inside the inner membrane.
18
Q
Cytoplasmic or extranuclear inheritance
A
mitochondria can replicate via binary fission
the transmission of genetic material independent of the nucleus
19
Q
mitochondria can replicate via ____
A
binary fission
20
Q
lysosomes
A
membrane bound structures containing hydrolytic enzymes that are capable of breaking down many different substrates including substances ingested by endocytosis and cellular waste products.
o Function in conjunction with endosomes, which transport, package, and sort cell material travelling to and from the membrane.
Endosomes are capable of transporting materials to the trans golgi, to the cell membrane, or to the lysosomal pathway for degradation.
o Hold in their hydrolytic enzymes. When they release their enzymes via autolysis, it directly leads to the degradation of cellular components.
21
Q
endosomes
A
which transport, package, and sort cell material travelling to and from the membrane.
Endosomes are capable of transporting materials to the trans golgi, to the cell membrane, or to the lysosomal pathway for degradation.
22
Q
endoplasmic reticulum
A
a series of interconnected membranes that are actually contiguous with the nuclear envelope.
o Double membrane is folded, and has a central lumen.
o Rough ER (RER): studded with ribosomes, which permit the translation of proteins destined for secretion directly into its lumen.
o Smooth ER (SER): mainly for lipid synthesis and detoxification of drugs. Transports proteins from the RER to the Golgi apparatus.
23
Q
rough ER
A
studded with ribosomes, which permit the translation of proteins destined for secretion directly into its lumen.
24
Q
smooth ER
A
mainly for lipid synthesis and detoxification of drugs. Transports proteins from the RER to the Golgi apparatus.
25
golgi apparatus
consists of stacked membrane bound sacs.
o Materials from the ER are transferred here in vesicles
o Make modifications (add carbohydrates, phosphates, and sulfates) and also attach signal sequences to things.
o Repackaged into vesicles and then sent to its correct location
26
peroxisomes
contain hydrogen peroxide.
o Main function is to break down very long chain fatty acids via Beta-oxidation.
o Participate in the synthesis of phospholipids and contain some of the enzymes involved in the pentose-phosphate pathway.
27
cytoskeleton
provides structure to the cell and helps it to maintain its shape.
o Also used for transport of materials around the cell
28
what are the 3 types of cytoskeleton
microfilaments
microtubules
intermediate filaments
29
microfilaments
made up of solid polymerized rods of actin.
The actin filaments are organized into bundles and networks and are resistant to compression and fracture.
Interact with myosin to generate force for movement.
Play a role in cytokinesis, forming the cleavage furrow, actin filaments contract and pinch off the connection between the two daughter cells.
30
what cytoskeletal component is involved in movement, muscle contraction
actin
31
microtubules
hollow polymers of tubulin proteins.
Provide pathways for motor proteins kinesin and dynein to carry vesicles.
Cilia and flagella are composed of MT
• Cilia: projections from a cell that are primarily involved in the movement of materials along the surface of the cells.
o Ex: movement of mucus in the respiratory tract.
• Flagella: structures involved in the movement of the cell itself
o Ex: sperm through the reproductive tract.
• The two share the same structure, 9 pairs of MT on the outer ring and 2 MT in the center: 9+2 structure
o Only seen in eukaryotic organelles of motility.
Centrioles: found in a region of the cell called the centrosome.
• The organizing centers for MT and are structured as nine triplets of MT with a hollow center.
• Migrate to opposite sides of the dividing cell during mitosis and organize the mitotic spindle.
o The MT emanate from them and attach to chromosomes via complexes called kinetochores
32
kinesin, myosin, dynein
actin: myosin
tubulin: kinesin and dynein
33
what are cilia and flagella composed of
microtubulues
34
cilia
projections from a cell that are primarily involved in the movement of materials along the surface of the cells.
o Ex: movement of mucus in the respiratory tract.
9 pairs of MT on the outer ring and 2 MT in the center: 9+2 structure
o Only seen in eukaryotic organelles of motility.
35
flagella
structures involved in the movement of the cell itself
o Ex: sperm through the reproductive tract.
9 pairs of MT on the outer ring and 2 MT in the center: 9+2 structure
o Only seen in eukaryotic organelles of motility.
36
centrioles
found in a region of the cell called the centrosome.
• The organizing centers for MT and are structured as nine triplets of MT with a hollow center.
• Migrate to opposite sides of the dividing cell during mitosis and organize the mitotic spindle.
o The MT emanate from them and attach to chromosomes via complexes called kinetochores.
37
intermediate filaments
diverse group of filamentous proteins, which includes keratin, desmin vimentin, and lamins.
Involved in cell-cell adhesion or maintenance of the integrity of the cytoskeleton.
Able to withstand a tremendous amount of tension.
38
what are the 4 different types of tissue?
epithelial, connective, muscle, and nervous
39
epithelial tissue
cover the body and line its cavities, providing a means for protection against pathogen invasion and desiccation.
Tightly joined to each other and to an underlying layer of connective tissue known as the basement membrane.
Diverse role depending on the organ.
• In most organs they constitute the parenchyma: the functional parts of the organ.
Polarized: one side faces a lumen of the organ or the outside world while the other side interacts with underlying blood vessels and structural cells.
Classified based on the number of layers and their shape:
• Simple epithelia: one layer of cells
• Stratified epithelia: have multiple layers
• Pseudostratified epithelia: appear to have multiple layers due to differences in cell height but in reality are only one layer.
• Cuboidal: cells are cube-shaped
• Columnar: cells are long and thin
• Squamous: cells are flat and scale-like.
40
basement membrane
underlying layer of connective tissue under epithelial tissue
41
simple epithelia
one layer of cells
42
stratified epithelia
have multiple layers
43
pseudo-stratified epithelia
appear to have multiple layers due to differences in cell height but in reality are only one layer.
44
cuboidal
cells are cube-shaped
45
columnar
cells are long and thin
46
squamous
cells are flat and scale-like.
47
connective tissue
supports the body and provides a framework for the epithelial cells to carry out their functions.
Contribute to the stroma or support structure of the organ.
Ex: bone, cartilage, tendons, ligaments, adipose tissue, and blood are all connective tissues.
Most cells in connective tissues produce and secrete materials such as collagen and elastin to form the extracellular matrix.
48
stroma
support system of the organ
| connective tissue
49
prokaryotes
o Include all bacteria
o Do not contain any membrane bound organelles
o Genetic material is organized into a single circular molecule of DNA concentrated into an area of the cell called the nucleoid region.
50
what are the prokaryotic domains?
archaea and bacteria
51
archaea
Single-celled organisms that are visually similar to bacteria, but contain genes and several metabolic pathways that are more similar to eukaryotes than bacteria.
Once classified as extremophiles: able to live in harsh environments
Ability to use alternative energy sources.
Live in the human body.
To eukaryotes:
• Similar: start translation with methionine, contain similar RNA polymerases, and associate DNA with histones.
• Different: single circular chromosome, divide by binary fission or budding, and have similar structure to bacteria.
52
bacteria
All contain a cell membrane and cytoplasm, and some have flagella or fimbriae (similar to cilia).
Flagella and ribosome are very different than eukaryotic and are targeted by antibiotics.
Some are mutualistic symbiotes: both humans and bacteria benefit from the relationship.
• Ex: some bacteria in the gut
Others are pathogens or parasites: they provide no advantage or benefit to the host, but rather cause disease.
• Can live inside or outside of cells.
53
extremophiles
able to live in hard environments
54
how are archaea similar and dissimilar to eukaryotes
* Similar: start translation with methionine, contain similar RNA polymerases, and associate DNA with histones.
* Different: single circular chromosome, divide by binary fission or budding, and have similar structure to bacteria.
55
bacteria and eukaryotes are different?
- Flagella and ribosome are very different than eukaryotic and are targeted by antibiotics.
56
mutualistic symbiotes
both humans and bacteria benefit from the relationship.
| • Ex: some bacteria in the gut
57
pathogens or parasites
they provide no advantage or benefit to the host, but rather cause disease.
• Can live inside or outside of cells.
58
what are the 3 shapes of bacterial cells?
cocci
bacilli
spirilli
59
cocci bacteria
spherical shape
60
bacilli bacteria
rod shaped
61
spirilli bacteria
spiral shaped (very few of these)
62
obligate aerobes
bacteria that require oxygen for metabolism
63
anaerobes
use another method other than oxygen for metabolism
Obligate anaerobes: cannot survive in an oxygen-containing environment
Facultative anaerobes: can use oxygen for aerobic metabolism when it is present and can also switch to anaerobic metabolism if it is not.
Aerotolerant anaerobes: unable to use oxygen for metabolism but are not harmed by its presence in the environment.
64
obligate anaerobes
cannot survive in an oxygen-containing environment
65
facultative anaerobes
can use oxygen for aerobic metabolism when it is present and can also switch to anaerobic metabolism if it is not.
66
aerotolerant anaerobes
unable to use oxygen for metabolism but are not harmed by its presence in the environment.
67
cell wall
prokaryotes
Cell wall (outer barrier) + cell membrane (plasma membrane) which is composed of phospholipids = envelope.
Provides structure and controls movement of solutes into and out of the bacterium.
Gram positive vs. gram negative: if the envelope absorbs a crystal violet stain or not. Positive = purple negative = red
• Gram positive: cell walls consist of thick layer of peptidoglycan: a polymeric substance made from amino acids and sugars. Cell wall also contains lipoteichoic acid: might activate the human immune system
• Gram negative: thin and also contain peptidoglycan but in smaller amounts. Cell walls and cell membrane are separated by periplasmic space. Also have outer membranes containing phospholipids and lipopolysaccharides (triggers immune response in humans, much stronger than lipoteichoic).
68
prokaryotes: cell wall + cell membrane =
envelope
69
gram positive vs. gram negative prokaryotes
if the envelope absorbs a crystal violet stain or not and then a counterstain of safranin or not. Positive = purple negative = pink/red
70
prokaryotes: flagella
long, whip like structures used for propulsion. Can have more than one.
Chemotaxis: the ability of a cell to detect chemical stimuli and move toward or away from something.
Composed of a filament, a basal body, and a hook:
• Filament: hollow, helical structure composed of flagellin
• Basal Body: a complex structure that anchors the flagellum to the cytoplasmic membrane and is also the motor of the flagellum which rotates.
• Hook: connects so the filament and the basal body
Similar for both gram positive and gram-negative bacteria.
71
prokaryotes: chemotaxis
the ability of a cell to detect chemical stimuli and move toward or away from something.
72
prokaryotes: describe the structure of a flagella
Composed of a filament, a basal body, and a hook:
• Filament: hollow, helical structure composed of flagellin
• Basal Body: a complex structure that anchors the flagellum to the cytoplasmic membrane and is also the motor of the flagellum which rotates.
• Hook: connects so the filament and the basal body
73
prokaryotes: plasmids
carry DNA acquired from external sources on small circular structures.
• Not part of the genome of the bacteria but may confer an advantage such as antibiotic resistance.
carry extragenomic material that may be helpful to the bacteria’s survival.
Virulence factors: traits that increase pathogenicity, such as toxin production, projections that allow attachment to certain kinds of cells, or features that allow evasion from the host’s immune system.
Episomes: subset of plasmids that can integrate into the genome of the bacterium.
74
prokaryotes other organelles
Ribosome: different in size
No mitochondria, electron transport chain is on the cell membrane
Cytoskeleton: not as complex as eukaryote.
75
prokaryotes: binary fission
: simple form of asexual reproduction seen in prokaryotes.
o Has fewer steps so it can proceed more rapidly than mitosis.
o The chromosome replicates while the cell grows in size, until the cell wall begins to grow inward along the midline of the cell and divides it into two identical daughter cells.
76
virulence factors
traits that increase pathogenicity, such as toxin production, projections that allow attachment to certain kinds of cells, or features that allow evasion from the host’s immune system.
77
episomes
subset of plasmids that can integrate into the genome of the bacterium.
78
what are the 3 methods of prokaryotic recombination
transformation
conjugation
transduction
79
prokaryote: transformation
results from the integration of foreign genetic material into the host genome.
This occurs after a nearby bacterial cell lyses.
Lots of gram negative rods can do this
80
prokaryote: conjugation
the bacterial form of mating (sexual reproduction).
Two cells form a conjugation bridge between them that facilitates the transfer of genetic material. Made from appendixes called sex pili that are on the donor male. To form the pilis, bacteria must contain plasmids known as sex factors that have the necessary genes.
• Best studied sex factor is the fertility factor: replicated and passed along from cell to cell.
• High frequency of recombination cells (Hfr): when the F-plasmid has integrated into the chromosomal DNA via transformation.
Transfer is unidirectional from the donor male (+) to the recipient female (-)
81
prokaryote: transduction
requires a vector: a virus that carries genetic material from one bacterium to another.
Bacteriophages: viruses that infect bacteria, can accidentally incorporate a segment of host DNA during assembly.
Bacteriophage infects another cell and releases the old host’s DNA which can then be integrated into the new host genome.
82
to form pilus for conjugation:
bacteria must contain plasmids known as sex factors that contain the necessary genes.
Have this plasmid: F+ cells.
83
transduction
requires a vector: a virus that carries genetic material from one bacterium to another.
Bacteriophages: viruses that infect bacteria, can accidentally incorporate a segment of host DNA during assembly.
Bacteriophage infects another cell and releases the old host’s DNA which can then be integrated into the new host genome.
84
vector
a virus that carries genetic material from one bacterium to another.
85
bacteriophage
viruses that infect bacteria, can accidentally incorporate a segment of host DNA during assembly.
viruses that specifically target bacteria.
o Don’t actually enter, just inject their genetic material
o Tail sheath: acts like a syringe, injecting genetic material into the bacteria
o Tail fibers: help the bacteriophage recognize and connect to the correct host cell.
86
transposons
genetic elements capable of inserting and removing themselves from the genome: eukaryotes and prokaryotes.
87
describe bacterial growth
o Lag phase: bacteria adapt to the new environment
o Exponential phase (log phase): bacteria have adapted, now show exponential growth
o Stationary phase: reduction of resources, slows bacteria reproduction.
o Death phase: the bacteria have exceeded the ability of the environment to support the number of bacteria, marks the depletion of resources.
88
viruses
• Viruses lack organelles and a nucleus and are tiny.
• Viruses are composed of genetic material, a protein coat and sometimes an envelope containing lipids.
o The genetic information may be circular or linear, single or double stranded and composed of either DNA or RNA.
89
virus: capsid
protein coat, which can also be surrounded by an envelope composed of phospholipid and virus specific proteins.
o the envelope is very sensitive.
90
difference between bacteriophage tail sheath and tail fibers
tail sheath: acts like a syringe, injecting genetic material into the bacteria
tail fibers: help the bacteriophage recognize and connect to the correct host cell.
91
viruses are obligate intracellular parasites:
cannot reproduce on their own.
| o Must infect a host cell and use its machinery to replicate and produce viral progeny, virions.
92
bacteria single stranded positive sense RNA genome
the genome may be directly translated to functional proteins by the ribosomes of the host cell.
93
bacteria single stranded negative sense RNA genome
acts as a template for synthesis of the complementary strand which can then be used for protein synthesis.
• These viruses must carry RNA replicase in the virion to make sure the useful strand gets synthesized.
94
retrovirus
enveloped, single-stranded RNA viruses.
Reverse transcriptase: synthesizes DNA from single stranded RNA.
The DNA integrates into the host cell genome where it is replicated and transcribed.
Integrates genetic material into the host cell genome and infects it indefinitely.
95
discuss the viral life cycle
infection
translation and progeny assembly
progeny release
lytic or lysogenic cycle
96
viral life cycle: infection
Some viruses fuse with the cell membrane while others just bind and inject in their genetic material. Can also be brought in by endocytosis.
Viruses can only infect a specific set of cells which depends on the receptors on the host cell.
97
viral life cycle: translation and progeny assembly
DNA or RNA viral genomes must be taken to correct location to be transcribed/translated.
Uses the ribosomes, tRNA, amino acids, and enzymes of the host cell.
Proteins that are made include proteins that make the capsid and envelope.
Must also make a new copy of the viral genome to be packaged into the capsid.
98
viral life cycle: progeny release
1. Viral invasion kills the cell and cycle starts upon viral entry
2. Cell lyses because of the large number of virions
3. Extrusion: the virus leaves by fusing with the plasma membrane. Keeps the host cell alive so that it can be used further, productive cycle.
99
viral life cycle: lytic and lysogenic cycles
Lytic cycle: maximizes the cell’s machinery and kills the cell. Viruses in the lytic phase are virulent.
Lysogenic cycle: the virus integrates into the host genome as a provirus or prophage.
• The virus will replicate as the bacterium reproduces.
Superinfection: simultaneous infection with many phages.
100
lytic cycle for virus
maximizes the cell’s machinery and kills the cell. Viruses in the lytic phase are virulent.
101
lysogenic cycle for virus
the virus integrates into the host genome as a provirus or prophage.
• The virus will replicate as the bacterium reproduces.
virus can remain dormant in the host genome.
102
extrusion
the virus leaves by fusing with the plasma membrane. Keeps the host cell alive so that it can be used further, productive cycle.
103
superinfection
simultaneous infection with many phages.
104
prions
infectious proteins and are nonliving things.
Cause disease by triggering misfolding of other proteins proteins become harder to degrade, build up.
Converts a protein from an alpha-helical structure to a Beta-pleated sheet structure.
105
viroids
small pathogens consisting of a very short circular single-stranded RNA that infect plants.
Can bind to RNA sequences and silence genes in the plant genome. leads to metabolic and structural changes.
Also some in humans (Example HepD).
106
prions and viroids
small subviral particles that can cause disease.
107
The nuclear envelope allows for ________
compartmentalization: separates where transcription and translation occur.
108
Nuclear pores
in the nuclear membrane and allow selective two-way exchange of material between the cytoplasm and the nucleus.
109
Nucleolus
where ribosomal RNA (rRNA) is synthesized. Darker spot on the nucleus.
110
histones
proteins that help to organize DNA by having linear DNA wound around them.
111
what is special about the way cristae are structured
they have numerous infoldings which allows for greater surface area (electron transport chain).
112
Releasing enzymes from the ______ can kick start _____ or _______
mitochondria
apoptosis
programmed cell death
113
autolysis
releasing enzymes from lysosomes. Leads to apoptosis through direct degradation of cellular components.
114
smooth ER vs rough ER
rough ER is studded with ribosomes. This permits the translation of proteins destined for secretion into its lumen.
the smooth ER does not have ribosomes and is primarily used for lipid synthesis (such as phospholipids) and the detoxification of certain drugs and poisons.
115
How do materials get from the ER to the Golgi
vesicles
116
kinesin and dynein are ____ while myosin is used to ____
motor proteins
| generate force for movement
117
the microtubules from the centrioles attach to _____ on chromosomes during mitosis.
kinetochores
118
which has a hollow center: microfilaments or microtubules?
microtubules
119
Which is 9+2 structure and which is 9 and explain difference
Flagella and cilia are 9+2: 9 doublet ring and 2 on inside
| Centrioles: 9 triplet ring and hollow in the middle.
120
parenchyma
oftentimes made up of epithelial cells and is the functional part of the organ
121
Name some examples of connective tissue
bone, cartilage, tendons, ligaments, adipose tissue, and blood are all connective tissues.
122
compared to eukaryotes, prokaryotes lack a ____ and _____
nucleus and membrane bound organelles
123
list all of the organelles
nucleus, mitochondria, lysosomes, endoplasmic reticulum, golgi apparatus, and peroxisomes
124
list all of the organelles
nucleus, mitochondria, lysosomes, endoplasmic reticulum, golgi apparatus, and peroxisomes
125
bacterial cells have no _____ so the electron transport chain is located on the ______
mitochondria
| plasma membrane
126
gram positive cell walls consist of a thick layer of ____
peptidoglycan and lipoteichoic acid
127
gram negative cell walls consist of a thin layer of _____. They also contain _____ instead of lipoteichoic acid
peptidoglycan
| lipopolysaccharides
128
is gram positive or gram negative cell wall more triggering to host immune system?
gram negative
129
periplasmic space
The periplasm is a concentrated gel-like matrix in the space between the inner cytoplasmic membrane and the bacterial outer membrane called the periplasmic space in gram-negative bacteria.
there is still even a cell wall outside of this double membrane.
130
flagella: the _____ connects the ___ to the _____
hook
| filament to the basal body
131
gram positive bacteria contain no ______
outer membrane
132
virion
viral progeny
133
what is RNA replicase used for
RNA replicase is used when a virus uses negative sense strand RNA to reproduce. It produces the complementary strand so that it can then be translated properly to form the viral particles necessary.
134
process by which a virion leaves the host cell but the host cell stays intact ____. This state is called ___.
extrusion
| productive cycle
135
Name some types of connective tissue
bones, tendons, cartilage, ligaments, adipose tissue, and blood.
136
mitochondrial DNA is _____, _____, and _____
single, circular, and double stranded DNA that can replicate by binary fission.
137
Are ribosomes surrounded by a single or double membrane?
neither: they are found in prokaryotes so they must not be membrane bound
138
what is the name of viruses that contain tail fibers and a sheath
bacteriophages, which only infect bacteria.
