Cell and Molecular Physiology Flashcards
(76 cards)
1
Q
maintenance of nearly constant conditions in the internal environment compatible with life
A
Homeostasis
2
Q
Total Body Weight
A
60% of body weight
3
Q
Intracellular Fluid (ICF)
A
40% of body weight
4
Q
Extracellular Fluid (ECF)
A
20% of body weight
5
Q
also called the internal environment of the body, or the milieu intérieur
A
Extracellular Fluid
6
Q
- large amounts of sodium, chloride, and bicarbonate ions
* nutrients for the cells, such as oxygen, glucose, fatty acids, and amino acids
A
Extracellular Fluid
7
Q
- large amounts of potassium, magnesium, and phosphate ions
- special mechanisms for transporting ions through the cell membranes maintain the ion concentration differences between ECF and ICF
A
Intracellular Fluid
8
Q
considered to be a state of disrupted homeostasis
A
Disease
9
Q
Fast; neurons; electrical impulse; external environment; for nervous coordination
A
Nervous Control
10
Q
Slow; hormones; organic message; internal environment; for chemical coordination
A
Hormonal Control
11
Q
Is separated from the cytoplasm by a nuclear membrane
A
Nucleus
12
Q
separated from the surrounding fluids by a cell membrane or plasma membrane
A
Cytoplasm
13
Q
collective term for different substances that make up the cell
A
Protoplasm
14
Q
Five basic substances of Protoplasm
A
O Water O Electrolytes O Proteins O Lipids O Carbohydrates
15
Q
25% of Extracellular Fluid (ECF)
A
Plasma
16
Q
75% of Extracellular Fluid
A
Interstitial Fluid
17
Q
- principal fluid medium of the cell
* present in most cells, except for fat cells, in a concentration of 70-85 percent
A
Water
18
Q
- inorganic chemicals for cellular reactions
* necessary for operation of some of the cellular control mechanisms
A
Electrolytes / Ions
19
Q
• constitute 10 to 20 percent of the cell mass
A
Protein
20
Q
Proteins can be divided into
A
O Structural Proteins
O Functional Proteins
21
Q
• long intracellular filaments that form microtubules and fibrillar proteins
EXAMPLES
- cytoskeleton of cellular organelles
- fibrillar proteins in collagen and elastin fibers
A
Structural Proteins
22
Q
Composed of combinations of a few molecules in tubular-globular form
EXAMPLES:
- Enzymes
A
Functional Proteins
23
Q
Substances that catalyze specific intracellular chemical reactions
A
Enzymes
24
Q
How fast can enzyme speed up chemical reactions?
A
10^6
25
Soluble in fat solvents but insoluble in water; Eg. Phospholipids and Cholesterol, Triglycerides
Lipids
26
- 2% of total cell mass
| - forms the cell membrane and membrane barriers
Phospholipids and Cholesterol
27
- in fat cells, constitutes 95% of the cell mass
- storehouse of energy-giving nutrients
- also called as neural fat
Triglycerides
28
* little structural function in the cell except as parts of glycoprotein molecule
* play a major role in cellular nutrition
Carbohydrates
29
- also called plasma membrane
- thin, pliable, elastic structure (7.5 to 10 nm)
- its basic structure is a lipid bilayer
Cell Membrane
30
Most abundant of the cell membrane lipids
Phospholipids
31
- mainly help determine the degree of permeability of the bilayer to water-soluble constituents of body fluids
- controls much of the fluidity of the membrane
Cholesterol
32
- Act as Guardian of the Cell
- Made up of a lipid bilayer (Fluid Mosaic Model)
- Divides the body into ECF and ICF compartments
Cell Membrane
33
* phosphate end of each phospholipid soluble in water (hydrophilic end)
* fatty acid end soluble only in fats (hydrophobic end)
* repelled by water but are mutually attracted to one another
* natural tendency to attach to one another in the middle of the membrane
Phospholipid Bilayer
34
Possession of both hydrophilic and hydrophobic properties make phospholipids ____ molecules
Amphipathic
35
2 Types of Cell Membrane Proteins
1. Integral Proteins
| 2. Peripheral Proteins
36
- anchored and embedded in the cell membrane through hydrophobic interactions
- may span the cell membrane (transmembrane proteins)
Integral Proteins
37
- not embedded in the cell membrane
- are not covalently bound to membrane components
- loosely attached to the cell membrane by electrostatic interactions
Peripheral Proteins
38
* loose carbohydrate coat of the cell membrane
| * carbohydrates in combination with proteins (glycoproteins) or lipids (glycolipids)
Glycocalyx
39
Are carbohydrate substances bound to small protein cores
Proteoglycans
40
Functions of the glycocalyx include:
o imparts a negative electrical charge
o attachment to glycocalyx of other cells
o receptor substances for binding hormones
o immune reactions
41
* specialized cellular subunit found in the cytoplasm that has a specific function
* usually separately enclosed within its own lipid bilayer (membrane-bound)
* may be identified by microscopy or purified by cell fractionation
Cellular Organelles
42
The jelly-like fluid portion of the cytoplasm in which particles are dispersed
Cytosol
43
* network of tubular and flat vesicular structures in the cytoplasm
* space inside the tubules and vesicles is filled with endoplasmic matrix
* space inside the endoplasmic reticulum is connected with the space between the two membrane surfaces of the nuclear membrane
Endoplasmic Reticulum
44
* also called granular endoplasmic reticulum
| * large numbers of ribosomes are attached to the outer surfaces; function in protein synthesis
Rough Endoplasmic Reticulum
45
o Aka agranular endoplasmic reticulum
o has no attached ribosomes
o Functions: Detoxification of substances and Lipid Synthesis
Smooth Endoplasmic Reticulum
46
Protein synthesis bound for Cell membrane, lysosomes and outside of the cell
Ribosomes in Rough Endoplasmic Reticulum
47
create protein bound for the cytoplasmic membrane, mitochondria and cytoplasm
Free Floating Ribosomes
48
* closely related to the endoplasmic reticulum
* composed of four or more stacked layers of thin, flat, enclosed vesicles lying near one side of the nucleus
* functions include: packaging of proteins and molecular tagging
* prominent in secretory cells
Golgi Apparatus
49
* vesicular organelles that form by breaking off from the Golgi apparatus
* intracellular digestive system for damaged cellular structures, food particles and bacteria
* called suicide bags of cells
Lysosomes
50
Programmed cell death/cell suicide; doesn't have inflammation
Apoptosis
51
not programmed cell death; positive for inflammation
Necrosis
52
• differences with lysosomes: formed by self-replication or budding from SER; and contain oxidase and catalase enzymes
• functions include:
o oxidizes many poisonous substances
o degrades free radicals that may damage cells
Peroxisomes
53
• also called secretory granules
• formed by the ER-Golgi apparatus system
• functions include
- storage for enzymes that are not yet activated
- replenish the plasma membrane whenever it forms phagocytic or pinocytic vesicles
Secretory Vesicles
54
storage for enzymes that are not yet activated
Proenzymes
55
- Powerhouse of the cell
| - forms adenosine triphosphate (ATP) the universal energy currency
Mitochondria
56
Unique Characteristics of Mitochondria
- self-replicative
- does NOT follow genetic code
- mitochondrial DNA is purely maternally-derived
57
* fibrillar proteins synthesized by ribosomes in the cytoplasm
* function is to provide rigid physical support for certain parts of cells (intracellular scaffolding)
Cytoskeleton
58
* control center of the cell
| * contains large quantities of DNA (genes)
Nucleus
59
• also called nuclear envelope
• two separate bilayer membranes
o outer membrane is continuous with the endoplasmic reticulum of the cell cytoplasm
• penetrated by several thousand nuclear pores
o large complexes of protein molecules are attached
o allow molecules up to 44,000 molecular weight to
pass through with reasonable ease
Nuclear Membrane
60
* unlike most other organelles, does not have a limiting membrane
* accumulation of large amounts of RNA and ribosomal proteins
* becomes considerably enlarged when the cell is actively synthesizing protein
Nucleolus
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Assembly Factory
Rough Endoplasmic Reticulum
62
Mr. Clean
Smooth ER
63
Post Office
Golgi Apparatus
64
Suicide Bag
Lysosomes
65
Taxi
Secretory Vesicles
66
Powerplant
Mitochondria
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Command Center
Nucleus
68
Scaffolding
Cytoskeleton
69
- secretory vesicles fuse with the cell membrane, extruding their contents outside the cell
- Ca2+-dependent process
Exocytosis
70
- molecules are absorbed and internalized by coating with membrane phospholipids forming a vesicle that detaches from cell membrane
- Maybe Phagocytosis or Pinocytosis
Endocytosis
71
Also known as cell eating
Phagocytosis
72
Process of Phagocytosis
- contact
- invagination
- invagination pinches off from cell membrane
- formation of membrane-enclosed vacuole
73
♣ also known as cell drinking
♣ primarily for absorption of extracellular fluids
♣ involves vesicles much smaller in size
♣ requires considerable amounts of ATP
Pinocytosis
74
- “Crawling” movement; E.g. WBC
Amoeboid Movement
75
- “To-and-fro” whip-like movement; E.g. Respiratory Epithelium and Fallopian Tubes
Ciliary Movement
76
- “rotatory” movement; E.g. flagella of the sperm cell
Flagellar Movement
