Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Cells > Flashcards

Cells Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What is the cell theory?

A
  1. The cell is the basic functional unit of life.
  2. All living things are made of cells.
  3. Cells come only from preexisting cells.
  4. Cells carry genetic info in the form of DNA and pass it on from parent to daughter cell.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Are viruses living organisms?

A

No. They may use RNA as their genetic info. They can only replicate by invading other organisms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the difference between prokaryotes and eukaryotes? What is the same?

A

Prokaryotes - unicellular and don’t have a nucleus or membrane-bound organelles, eukaryotes - either uni or multicellular and have a nucleus/organelles. Both have ribosomes, and double stranded DNA.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Features of nucleus

A
  • Contains DNA wound around histones and into linear strands (chromosomes).
  • Has double nuclear membrane with pores for selective permeability.
  • Nucleolus spot where rRNA is made.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Features of mitochondria

A
  • Outer membrane and inner (folded into cristae for SA maximization).
  • Location of ETC - pumping of protons from matrix to intermembrane space creates proton-motive force and makes ATP.
  • Have their own genes and reproduce thru binary fission - extranuclear inheritance.
  • Can kick off apoptosis by releasing enzymes from ETC.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Features of lysosomes

A
  • Contain hydrolytic enzymes.
  • Work with endosomes, which transport and sort cell material traveling to/from membrane.
  • Can release its enzymes for apoptosis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Features of endoplasmic reticulum

A
  • Membranes continuous with nuclear envelope.
  • Rough ER: translates proteins secreted directly into its lumen.
  • Smooth ER: lipid synthesis (such as phospholipids), detoxification of drugs/poisons, protein transport from RER to Golgi.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Features of Golgi apparatus

A
  • Receives and modifies products thru addition of chemical groups/signal sequences.
  • Sends out vesicles to product destinations.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Features of peroxisomes

A
  • Contain hydrogen peroxide.
  • Breakdown very long fatty acid chains via beta-oxidation.
  • Help synthesize phospholipids.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Features of cytoskeleton

A
  • Provides structure, shape, transport.

- Made of microfilaments, microtubules, intermediate filaments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Features of microfilaments

A
  • Made of solid actin rods in bundles.
  • Resist compression and fracture (protect).
  • Form cleavage furrow during cytokinesis.
  • Macrophage movement.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Features of microtubules

A
  • Hollow tubulin polymers.
  • Transport routes for motor proteins (kinesin and dynein).
  • Make up cilia and flagella.
  • Make up centrioles.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

9+2 structure of cilia and flagella

A
  • 9 pairs of microtubules form an outer ring.

- 2 microtubules in the center.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Features of centrioles

A
  • Found in centrosome.
  • Made of 9 triplets of microtubules with a hollow center.
  • Organize mitotic spindle during mitosis.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Features of intermediate filaments

A
  • Diverse group, includes keratin.
  • Cell-cell adhesion, integrity of skeleton, anchor organelles.
  • Can withstand a lot of tension.
  • Can withstand compression forces.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Features of epithelial tissue

A
  • Adhere to underlying basement membrane of connective tissue.
  • Make up parenchyma (functional parts of organ).
  • Polarized (lumen/outside facing vs. underlying structure facing).
  • Classified by number of layers and shape.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Features of connective tissue

A
  • Make up stroma (support) of organs.
  • Bone, cartilage, tendons, adipose, blood.
  • Produce and secrete extracellular matrix (collagen, elastin).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How is prokaryotic genetic material organized?

A

Into a single circular DNA molecule in an area called the nucleoid region.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Features of archaea

A
  • Similar to eukaryotes: start translation with Met, contain similar RNA polys, associate DNA with histones.
  • Different from eukaryotes: single circular chromosome, divide by binary fission/budding, look overall similar to bacteria.
  • Use alt sources of energy.
  • Can be extremophiles.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Features of bacteria

A
  • All have cell membrane and cytoplasm.
  • Some have flagella or fimbriae (similar to cilia).
  • Smaller ribosomes than ours.
  • Mutualistic symbiotes vs. pathogens/parasites.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Possible bacteria shapes

A
  • Cocci: spheres
  • Bacilli: rods
  • Spirilli: spirals
22
Q

4 types of metabolic bacteria

A
  • Obligate aerobes: need oxygen for metabolism.
  • Obligate anaerobes: die in presence of oxygen.
  • Facultative anaerobes: can use oxygen or be anaerobic.
  • Aerotolerant anaerobes: can’t use oxygen for metabolism, but can survive around it.
23
Q

Difference between gram-positive and gram-negative bacteria?

A
  • Gram-positive: shows up purple. Cell wall is thick layer of peptidoglycan, with lipoteichoic acid (activates human immune system).
  • Gram-negative: shows up pink. Cell wall is very thin peptidoglycan layer separated from cell membrane by periplasmic space. Have outer membranes of phospholipids and lipopolysaccharides (much stronger human immune system response).
24
Q

Structure of bacterial flagella

A
  • Used in chemotaxis.
  • Filament part made of hollow flagellin.
  • Basal body part that anchors flagella to membrane and rotates as a motor.
  • Hook part connects basal body and filament.
  • Archaea also have flagella (but are different).
25
Q

What are plasmids?

A
  • Circular DNA from external sources that can give an advantage to the prokaryote.
  • May have virulence factors - traits that increase pathogenicity.
  • Episomes - plasmids that become a part of the genome.
26
Q

Organelles in prokaryotes

A

Primitive cytoskeleton and smaller ribosomes.

27
Q

What is binary fission?

A
  • Asexual reproduction in prokaryotes.
  • Circular chromosome replicates, cell grows, splits in two.
  • Creates two identical cells.
  • Can be very fast.
28
Q

Three types of bacterial genetic recombination?

A

Transformation, conjugation, transduction

29
Q

Transformation

A
  • Bacterial genetic recomb.
  • Integration of foreign genetic material into host genome.
  • Often done by gram-negative bacteria.
30
Q

Conjugation

A
  • Bacterial genetic recomb.
  • Sexual reproduction - two cells form conjugation bridge to transfer genetic info.
  • Bridge is made from sex pili appendages found on donor male (+).
  • Only those that have sex factor plasmids have the genes for sex pili (for example, F factor - F+ have it, F- don’t).
  • F+ cell will replicate its F factor and give it to the F- cell, creating another F+ - rapid spread.
  • Hfr (high frequency of recomb) cells - sex factor has become a part of host genome thru transformation, and entire genome replicates now, but usually the bridge breaks before the full DNA can be moved.
31
Q

Transduction

A

-Requires a vector - bacteriophages (virus) that accidentally takes a segment of host DNA and spreads it to new hosts.

32
Q

What is a transposon?

A

Genetic elements that can insert or remove themselves from the genome in both proks and euks.

33
Q

Phases of bacterial growth

A
  • Lag phase: bacteria first adapt to new environment (not much growth).
  • Exponential/log phase: intense growth.
  • Stationary phase: reduction of resources slows reproduction (nearly horizontal).
  • Death phase: depletion of resources, so they die.
34
Q

Structure of a virus

A
  • Genetic material: DNA or RNA, circular or linear, single or double stranded.
  • Capsid: protein coat
  • May have envelope of phospholipids and proteins, very sensitive.
35
Q

Structure of a bacteriophage

A
  • Nucleic acid in a capsid.
  • Tail sheath acts as syringe to inject genetic material into bacteria.
  • Tail fibers help virus find and attach to host.
36
Q

Positive vs. negative sense viruses

A
  • Single stranded RNA viruses
  • Positive sense: genome directly translated to proteins by host’s ribosomes.
  • Negative sense: virus’s RNA is a template for synthesis of a complementary strand, which is used for protein synthesis. Must contain RNA replicase in virion.
37
Q

What are retroviruses?

A
  • Enveloped, single stranded RNA viruses
  • Contain reverse transcriptase, which creates DNA from the single stranded RNA
  • This DNA integrates into host cell genome
  • Only way to remove virus is to kill cell
  • HIV
38
Q

Steps of a virus life cycle

A
  1. Infection
  2. Translation and Progeny Assembly
  3. Progeny Release
39
Q

Infection stage of virus life cycle

A
  • Virus binds to correct receptors on host cell
  • Envelopes can fuse with plasma membrane
  • Cell may mistake virus and bring it in
  • Bacteriophages inject their genome
  • Some use enzymes to get past cell membrane
  • Depending on virus, different portions of virion will be sent in
40
Q

Translation/progeny assembly stage of virus life cycle

A
  • DNA viruses must enter nucleus –> transcribed into mRNA –> translated into proteins
  • Pos RNA viruses send RNA to cytoplasm, where is directly translated
  • Neg RNA and retroviruses need complementary RNA strand or DNA strand (DNA will go to nucleus and get integrated)
  • Many of the proteins formed are capsid proteins, virions will assemble and be released
  • Viral genome must be returned to its original form in progeny
41
Q

Progeny release stage of virus life cycle

A
  • May initiate cell death, so progeny spills out
  • Host cell may lyse (disadvantage to virus)
  • Extrusion - virus can fuse with cell’s plasma membrane - keeps host alive (virus in productive cycle)
42
Q

What is a lytic cycle?

A
  • Life cycle of bacteriophage
  • Little regard for survival of host cell - cell will lyse
  • Viruses called virulent in this cycle
43
Q

What is a lysogenic cycle?

A
  • Life cycle of bacteriophage
  • Virus can integrate into host genome as a prophage/provirus
  • Can leave host genome any time due to environmental factors
  • Can actually benefit bacteria - makes bacteria less susceptible to superinfection (simultaneous infection)
  • Viruses have a dormant phase
44
Q

What is a prion?

A
  • Infectious proteins that can trigger misfolding of other proteins (convert alpha-helicals to beta-pleated sheets)
  • This reduces protein solubility and degradation, leading to aggregates
  • Ex: mad cow, fatal insomnia
45
Q

What is a viroid?

A
  • Pathogen with short circular single strand of RNA that can silence genes in plant genomes
  • Some human ones: Hepatitis D (with Hep B)
46
Q

What did Schleiden and Schwann find?

A

That all living things are made of cells

47
Q

What did Louis Pasteur’s neck flask experiment disprove?

A

Spontaneous generation

48
Q

Which of the following transcriptional control features are found in both prokaryotes and eukaryotes?

A

Promotor repressors - molecules that can bind to DNA at promoter sites and regulate transcription.

49
Q

Difference in prokaryote and eukaryote DNA replication

A

Prokaryotic polymerases work at a faster rate than eukaryotic ones

50
Q

A feature of microfilaments of a WBC?

A

Used to phagocytose a pathogen.

51
Q

Where does energy production take place in bacteria that can aerobically respirate?

A

Plasma membrane (no mitochondria, and need to establish concentration gradient)

Biology (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions