Chapter 3 Cellular Form And Function Flashcards
1
Q
Cell
A
Basic, living, structural, functional unit of the body
2
Q
Cytology
A
Study of cell structure
3
Q
Cell physiology
A
Study of cell function
4
Q
Squamous shape
A
Thin, flat, scaly
5
Q
Cuboidal shape
A
Square, cube
6
Q
Columnar shape
A
Taller than wide
7
Q
Polygonal shape
A
Irregular
8
Q
Stellate shape
A
Star-like
9
Q
Spheroid/ovoid shape
A
Round to oval
10
Q
Discoidal shape
A
Disk like
11
Q
Fusiform shape
A
Thick in middle
12
Q
Fibrous shape
A
Thread like
13
Q
Plasma membrane/ cell membrane
A
Flexible barrier that surrounds the cytoplasm of the cell, the membrane consists of a sea of lipids with proteins afloat
14
Q
Cytoplasm
A
Liquid that fills inside of cell
15
Q
Cytosol
A
Fluid portion
16
Q
Organelles
A
Internal cellular structures other than the nucleus
17
Q
Nucleus
A
Contains DNA or genetic material
18
Q
intracellular fluid (ICF)
A
The fluid within the body cells
19
Q
Extracellular fluid (ECF)
A
The fluid outside of body cells
20
Q
Interstitial fluid
A
ECF filling the narrow spaces between tissues
21
Q
Plasma
A
ECF in blood vessels
22
Q
Functions of the plasma membrane
A
-physical barrier
-Regulation of exchange of molecules and ions with the environment
-sensitivity to the environment
-structural support
23
Q
98% on membrane molecules are:
A
Lipids
24
Q
Phospholipid bilayer
A
The basic framework of the cell membrane
25
How do the phospholipids orient themselves within the bilayer?
By positioning themselves with the hydrophilic heads directed outwards and the hydrophobic tails directed inwards
26
Integral proteins
Embedded proteins in the plasma membrane that are exposed of ECF and/or ICF on one or both sides
27
Transmembrane proteins
Integral proteins that pass completely through the phospholipid bilayer
28
Peripheral proteins
Proteins loosely attached to either the inside or outside of the plasma membrane
29
Glycoproteins
Integral or peripheral proteins that have chains of sugar molecules attached to them located on the outside surface of the plasma membrane
30
Glycocalyx
Carbohydrate enriched coat formed by glycoproteins and glycolipids around the outside of the cell
31
Functions of glycocalyx
-act as signature sequence that allow cells to recognize one another
-adherence
-protection from digestion
-attracts water molecules
32
Receptor protein
Binds to chemical messengers, change inside the cell happens
33
Enzymes protein
Catalyzes reactions inside or outside of cell
34
Leakage channel protein
Allows polar molecules into cell, constantly open
35
Gated channel protein
Opens and closes
36
Cell indentity marker protein
Distinguishes body’s own cells from foreign cells
37
Cell adhesion molecule (CAM) protein
Fuses to another protein from another cell
38
Carrier protein
Moves substances across the plasma membrane by changing its shape
39
3 factors to open channels
-A chemical binding=ligand gated channel
-Electrical difference access= voltage gated channel
-mechanical deformation=mechanically gated channel
40
Selectively permeable
The plasma membrane allows some things to move across easily and not other things
41
Three types of membrane transport
Diffusion
Carrier mediated transport
Vesicular transport
42
Charge gradient
Inner surface of the cell is more negative and the outer surface is more positive
43
Chemical gradient
Concentration gradient across the cell membrane
44
Diffusion: shorter distance =
Faster diffusion
45
Diffusion: smaller substance=
Faster diffusion
46
Diffusion: higher temperature=
Faster diffusion
47
Diffusion: larger gradient =
Faster diffusion
48
The negative charge inside the membrane tend to favour:
The entry of cations
49
Diffusion: greater membrane area=
Faster diffusion
50
Simple diffusion
Small non polar and hydrophobic molecules can diffuse through the lipid bilayer. Large non polar molecules can get stuck in the membrane
51
Channel mediated diffusion
Each ion channel is specific for a particular ion
52
Osmosis
The movement (diffusion) of water through permeable barrier from an area of high concentration of water to a low concentration of water
53
Water moves through cells in two ways:
-Aquaporins; special channel proteins
-by slipping through temporary spaces between lipids caused by their movements
54
Tonicity
Relates to how the solution influences the shape of body cells
55
Isotonic
The concentrations of the solutes are the same on both sides of the membrane. Water molecules enter and exit at the same rate and cell stays a normal shape
56
Hypotonic
The concentrations of solutes is higher inside the cell and too much water moves into the cell.
Can cause hemolysis
57
Hypertonic
The concentrations of the solutes are lower inside the cell and not enough water moves in. Can cause crenation
58
Specificity
Each carrier protein binds and transports only certain substances
59
Saturation limits
The rate of substance transport is limited by the availability of carrier proteins
60
Regulation
The cell can control the activity of carrier proteins
61
Facilitated diffusion
Substances move down their concentration gradient so that no energy is required. Molecule binds to a carrier protein and alters the shape of the protein
62
Active transport
Energy requiring process in which carrier proteins move solutes regardless of the concentration gradient
63
Primary active transport
Energy from the hydrolysis of ATP changes the shape of a transport protein
64
The Na+/K+ pump
Maintains concentration gradients of Na+ and K+ across the membrane. 3 Na’s go out as 2 K’s go in through carrier protein.
65
How much of our body’s energy is spent making the sodium potassium pump run
40%
66
Secondary active transport
As Na+ leaks into the cell other substances can be transported into the same direction or the opposite direction (getting a free ride)
67
Vesicular transport
Molecules too large to be moved across membrane by passive or active transport cross in vesicles. Molecules in vesicles get pinched off and go across or through the membrane in the vesicle
68
Exocytosis
Movement of substances out of the cell. Vesicles are brought to the plasma membrane then fuses to the membrane releasing its cargo
69
Endocytosis
Movement of substances into a cell
70
3 types of endocytosis:
1. Phagocytosis- enzymes in the cells lysosomes eat the large particles
2. Pinocytosis- lysosomes drink the fluid surrounding the cell
3. Receptor mediated endocytosis- cells take up specific ligands
71
Transcytosis
Method by which substances can cross the cell
72
Cytosol
Fluid portion of the cytoplasm that surrounds the organelles
73
Organelles
Specialized structures that have characteristic shapes and perform functions in cellular metabolism
74
Cytoskeleton
Network of protein filaments and cylinders. Determines cell shape, supports structure, directs movement. Composed of: microfilaments, intermediate fibers, microtubules
75
Ribosomes
Small granules of protein and RNA
found in the nucleoli, Cytosol, outer surfaces of rough ER and nuclear envelope.
Read coded genetic messages and assemble amino acids into proteins
76
Endoplasmic reticulum
System of channels enclosed by membrane
77
Rough ER
Parallel flattened sacs covered with ribosomes.
Produces phospholipids and proteins
Synthesizes proteins that are packaged in other organelles
Often the largest organelle
78
Smooth ER
Lack ribosomes
Synthesizes steroids and other lipids
Calcium storage
Detoxifies alcohol and drugs
79
Golgi complex
System of cisterns that synthesizes carbohydrates and puts finishing touches on protein synthesis
80
Lysosomes
Package of enzymes bound by a membrane
Shape: mostly round
Functions: digestion of substances
81
Autophagy
Digestion of cells surplus organelles
82
Autolysis
Cell suicide, digestion of a surplus cell by itself
83
Peroxisomes
Resemble lysosomes but contain different enzymes and are produced by ER
Functions: produces hydrogen peroxide
Catalase breaks down excess H2O2
neutralize free radicals= detoxify drugs alcohol and other blood toxins
84
Mitochondria
Organelles specialized for synthesizing ATP
Powerhouse of the cell
85
Cilia
Function to move fluid and material along the cells surface
86
Flagella
Generate forward motion (sperm cells only)
87
Nucleus
Has its own membrane
Has genes
88
Nuclear envelope
Membrane surrounding nucleus similar to plasma membrane
89
Genes
The cells hereditary units consisting of DNA
90
How many chromosomes do human somatic cells have?
46 chromosomes arranged in 23 pairs and are diploid
91
How many chromosomes do human reproductive cells have?
23 chromosomes and are haploid
92
Stem cells
Continuously divide and give rise to more daughter cells
93
Apoptosis
Cell suicide, enzymes kill the cell
