Chapter 3 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

The theory of spontaneous generation

A

Life can arise from non-living matter

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

Francesco Redi’s experimental setup (1668)

A

A container, a container sealed with a cork top, and a container covered in mesh that let in air but not flies.

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

How did Louis Pasteur refute the theory of spontaneous generation?

A

Experimented using the unique swan-neck feature which allowed air to enter the flask but prevented the entry of bacterial and fungal spores.

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

What was the cell theory popularized in an 1855 essay entitled “Cellular Pathology.”

A

All cells arise from cells

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

The Endosymbiotic Theory

A

Mitochondria and chloroplasts are each derived from the uptake of bacteria. These bacteria established a symbiotic relationship with their host cell that eventually led to the bacteria evolving into mitochondria and chloroplasts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why were mothers more likely to die in hospitals than when treated by midwives?

A

Due to lack of handwashing by staff after touching infected bodies.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The Germ Theory of Disease

A

Handwashing to prevent transfer of disease between patients by physicians.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the cell theory state?

A

The cell is the fundamental unit of life.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 4 basic cell components?

A

Cytoplasm (a gel-like substance composed of water and dissolved chemicals needed for growth)
Plasma membrane/cell membrane/cytoplasmic membrane
One or more chromosomes (genetic information of the cell)
Ribosomes: the production of proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does a typical prokaryotic cell contain?

A

A cell membrane, chromosomal DNA that is concentrated in a nucleoid, ribosomes, and a cell wall.

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

What is a coccus cell shape?

A

Perfectly round

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the different arrangements of the coccus cells?

A

Coccus - single coccus
Diplococcus - pair of two cocci
Tetrad - grouping of 4 cells arranged in a square
Streptococcus - chain of cocci
Staphylococcus - cluster of cocci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a bacillus shape?

A

A straight rod

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

What are the arrangements of bacillus cells?

A

Bacillus - single bacillus
Streptobacillus - chain of rods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is a vibrio shape?

A

A curved rod.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a coccobacillus shape?

A

A short rod

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a spirillum shape?

A

A loose spiral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a spirochete shape?

A

Long, helical spiral

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

What is an isotonic solution?

A

Solute concentration is equal inside and outside of the cell. No net movement of water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a hypotonic solution?

A

Higher solute concentration inside the cell. Net water movement into the cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a hypertonic solution?

A

Lower solute concentration inside the cell. Net water movement out of the cell. Causes crenation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Crenation versus plasmolysis

A

Crenation - animal cells
Plasmolysis - plant cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the nucleoid?

A

Condensed area of DNA found within prokaryotic cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How are prokaryotic chromosomes described?

A

Circular, haploid (unpaired), and not bound by a complex nuclear membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the number for ribosomes in prokaryotic cells?

A

70S (30S & 50S)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is sporulation?

A

The process by which vegetative cells transform into endospores.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

When does sporulation occur?

A

When nutrients become depleted or environmental conditions become otherwise unfavorable.

28
Q

What is germination?

A

The reentering into a vegetative state from an endospore.

29
Q

What are 4 qualities of vegetative cells?

A
  • Sensitive to extreme temperatures and radiation
  • Gram-positive
  • Normal water content and enzymatic activity
  • Capable of active growth and metabolism
30
Q

What are 4 qualities of endospores?

A
  • Resistant to extreme temperatures and radiation
  • Do not absorb gram stain only special endospore stains
  • Dehydrated; no metabolic activity
  • Dormant; no growth or metabolic activity
31
Q

Transmembrane proteins versus peripheral proteins

A

Transmembrane go all the way through the plasma membrane.
Peripheral proteins are only on one side of the membrane.

32
Q

What is passive transport?

A

Simple diffusion down a concentration gradient directly across the membrane.

33
Q

What is facilitated diffusion?

A

Travel down a concentration gradient through a membrane protein.

34
Q

What is active transport?

A

Transport against a concentration gradient via a membrane pump that requires energy.

35
Q

What is the purpose of chlorophylls?

A

Photosynthesis

36
Q

Gram-positive versus gram-negative cell wall?

A
  • Gram-positive cell walls are structurally simple, containing a thick layer of peptidoglycan with embedded teichoic acid external to the plasma membrane.
  • Gram-negative cell walls are structurally more complex, containing a thin layer of peptidoglycan and an outer membrane containing lipopolysaccharides.
37
Q

What does acid staining do?

A

Detects the presence of cell walls that are rich in mycolic acid.
Red in color.

38
Q

What is the difference between fimbriae and pili?

A

Fimbriae are typically more numerous and shorter.
Pili are longer and less numerous per cell.
Both enable cells to attach to surfaces and to other cells. F pilus = sex pilus→ DNA transfer

39
Q

What are flagella?

A

Structures used by cells to move in aqueous environments (like propellers).

40
Q

What are the 3 basic structure elements?

A

Basal body, hook, and filament (the basal body composition and arrangement differ between gram-positive and
gram-negative bacteria).

41
Q

Look at image of gram-negative versus gram-positive bacteria.

A
42
Q

What are the 4 different arrangements of flagella?

A

Monotrichous - one flagella
Amphitrichous - one flagella out of each end of the bacteria
Lophotrichous - multiple flagella out of one end of the bacteria
Peritrichous - flagella coming from all over the body.

43
Q

Counterclockwise rotation versus clockwise.

A

Counterclockwise = run
Clockwise = tumbles

44
Q

Chemotaxis

A

Chemical gradient of an attractant → the length of runs is extended, while the length of tumbles is decreased.

45
Q

What are some unique characteristics eukaryotic cells?

A
  • The presence of a nucleus surrounded by a complex nuclear membrane.
  • Membrane-bound organelles in the cytoplasm.
  • Organelles are held in place by the cytoskeleton (supports transport of intracellular components and helps maintain cell shape).
46
Q

What is the role of the nucleus?

A
  • Eukaryotic cells have a well-defined nucleus surrounded by a nuclear membrane.
  • The DNA within the nucleus is highly organized and condensed to fit inside the nucleus (the DNA is wrapped around proteins called histones).
  • It controls all activities of the cell and serves an essential role in reproduction and heredity.
47
Q

What are coenocytes?

A

Cells whose nuclei divide, but whose cytoplasm does not.

48
Q

Know Mitosis versus Meiosis

A
49
Q

What is the nucleolus and what occurs there?

A

The nucleolus is the dark, dense area within the nucleus. It is the site of rRNA synthesis and pre-ribosomal assembly.

50
Q

What is the number for ribosomes in eukaryotic cells?

A

80S (30S + 50S)?

51
Q

What are membrane bound ribosomes?

A

They are attached to the rough endoplasmic reticulum and make proteins for insertion into the cell membrane or proteins destined for export from the cytoplasm.

52
Q

What are free ribosomes?

A

They are found in the cytoplasm and serve to synthesize water soluble proteins.

53
Q

What happens in the rough endoplasmic reticulum (RER)?

A

Ribosomes are bounded on the cytoplasmic side of the membrane.
Proteins are synthesized destined for the plasma membrane.
Transport vesicles → to the Golgi apparatus for further processing, directly to the plasma membrane, to the membrane of another organelle, or out of the cell.

54
Q

What happens in the smooth endoplasmic reticulum?

A

SER does not have ribosomes and, therefore, appears “smooth.”
It is involved in the biosynthesis of lipids, carbohydrate metabolism, and detoxification of toxic compounds within the cell.

55
Q

What is the Golgi apparatus?

A

Cup-shaped, stacked disks and several transport vesicles that modify lipids and proteins, producing glycolipids and glycoproteins → inserted into the plasma membrane.

56
Q

What is exocytosis?

A
57
Q

What are lysosomes?

A

Lysosomes are membrane-bound organelles of the endomembrane system that contain digestive enzymes.
They break down various particles, such as food, damaged organelles or cellular debris, microorganisms, or immune complexes.

58
Q

What is lysis?

A

Lysis is often associated with the process of destroying or breaking down.

59
Q

What is the cytoskeleton?

A

The cytoskeleton is a network of microfilaments, intermediate filaments, and microtubules found throughout the cytoplasm of a eukaryotic cell. It provides structural support as well as a network over which materials can be transported within the cell and on which organelles can be anchored.

60
Q

What is a microfilament?

A

A microfilament is composed of a pair of actin filaments. Each actin filament is a string of polymerized actin monomers. Allows microfilaments to be involved in a variety of cellular processes.

61
Q

What are intermediate filaments?

A

Intermediate filaments are composed of multiple strands of polymerized subunits. They form much of the nuclear lamina. Intermediate filaments form the desmosomes between cells in some animal tissues.

62
Q

What are microtubules?

A

Microtubules are hollow structures composed of polymerized tubulin dimers. They are involved in several cellular processes, including the movement of organelles throughout the cytoplasm.

63
Q

What is the mitochondrion?

A

It is surrounded by two membranes, the inner of which is extensively folded into cristae and is the site of the intermembrane space. The mitochondrial matrix contains the mitochondrial DNA, ribosomes, and metabolic enzymes. Aerobic cellular respiration occurs in eukaryotic → mitochondria.

64
Q

What is the eukaryotic plasma membrane composed of?

A

The eukaryotic plasma membrane is composed of a lipid bilayer with many
embedded or associated proteins (as prokaryotic plasma membrane). However, it contains sterols (cholesterol) and sphingolipids for the maintenance of membrane.

65
Q

What is an extracellular matrix?

A

Cells of animals and some protozoans do not have cell walls → extracellular matrix.
It is composed of protein and carbohydrates (Proteoglycans).
It protects cells from physical stresses and transmits signals arriving at the outside edges of the tissue to cells deeper within the tissue.