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Anatomy and Physiology Lecture > Chapter 3 - The Cellular Level of Organization > Flashcards

Chapter 3 - The Cellular Level of Organization Flashcards

1
Q

What are the main components that make up the Cell Theory?

A
  • Cells are the building blocks of all organisms
  • All cells come from the division of preexisting cells
  • Cells are the smallest units that perform all vital physiological functions
  • Each cell maintains homeostasis at the cellular level
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2
Q

What are the main types of Cells?

A

a. Sex cells (germ cells or reproductive cells)
- Male sperm
- Female oocytes (cells that develop into ova)
b. Somatic cells
- All body cells except sex cells

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3
Q

What are Centrosomes/Centrioles and what are the main functions?

A
  • Cytoplasms containing two centrioles at right angles (nonmembranous organelles)
  • Essential for movement of chromosomes during cell division
  • Organization of microtubules in cytoskeleton
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4
Q

What is the Cytoskeleton and what is its main function?

A
  • Proteins organized in fine filaments or slender tubes (nonmembranous organelles)
  • Functions in strength and support
  • Movement of cellular structures and materials
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5
Q

What is the Plasma Membrane?

A
  • Lipid bilayer containing phospholipids, steroids, proteins, and carbohydrates
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6
Q

What are the main functions of the Plasma Membrane?

A

a. Physical isolation
- Barrier
b. Regulation of exchange with environment
- Ions and nutrients enter
- Wastes eliminated and cellular products released
c. Sensitivity to the environment
- Extracellular fluid composition and chemical signals
d. Structural support
- Anchors cells and tissues

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7
Q

What is Microvilli and what is its main function?

A
  • Nonmembranous extensions of the plasma membrane containing microfilaments
  • Functions to increase surface area to facilitate absorption of extracellular materials
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8
Q

What are Cilia and what is its main function?

A
  • Nonmembranous long extensions of the plasma membrane containing microtubules (there are 2 types; primary and motile)
  • Primary cilium acts as a sensor
  • Motor cilia moves materials over cell surfaces
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9
Q

What are Proteasomes and what is its main function?

A
  • Nonmembranous hollow cylinders of proteolytic enzymes with regulatory proteins at their ends
  • Functions in breakdown and recycling of damaged or abnormal intracellular proteins
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10
Q

What are Ribosomes and what is its main function?

A
  • A nonmembranous combination of RNA and proteins
  • Two types
    a. Fixed ribosomes - bound to rough endoplasmic reticulum
    b. Free ribosomes - scattered in cytoplasm
  • Functions in protein synthesis
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11
Q

What is the Golgi Apparatus and what is its main function?

A
  • Membranous stacks of flattened membranes (cisternae) containing chambers
  • Functions in storage, alteration, and packaging of secretory products and lysosomal enzymes
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12
Q

What is the Mitochondria and what is its main function?

A
  • A double membrane with inner membrane folds (cristae) that enclose important metabolic enzymes
  • Functions in producing 95% of the ATP required by the cell
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13
Q

What is the Endoplasmic Reticulum and what is its main function?

A
  • A network of membranous channels extending throughout the cytoplasm
  • Functions in synthesis of secretory products, intracellular storage and transport, and detoxification of drugs or toxins
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14
Q

What are Peroxisomes and what is its main function?

A
  • Membranous vesicles containing degradative enzymes
  • Functions in catabolism of fats and other organic compounds, neutralization of toxic compounds generated in the process
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15
Q

What are Lysosomes and what is its main function?

A
  • Membranous vesicles containing digestive enzymes

- Functions in intracellular removal of damaged organelles or pathogens

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16
Q

What is the Nucleus?

A

A nucleoplasm containing nucleotides, enzymes, nucleoproteins, and chromatin, all surrounded by a double membrane (the nuclear envelope)

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17
Q

What is the main function of the Nucleus?

A
  • Control of metabolism
  • Storage and processing of genetic information
  • Control of protein synthesis
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18
Q

What is Extracellular Fluid?

A

Interstitial fluid; a watery medium that surrounds a cell

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19
Q

The Plasma Membrane (cell membrane) separates what?

A

Cytoplasm from the extracellular fluid

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20
Q

What are the components that make up the Phospholipid Bilayer?

A

a. Hydrophilic heads
- Face outward on both sides, toward watery environments
b. Hydrophobic fatty-acid tails
- Inside membrane

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21
Q

What is the main function of the Phospholipid Bilayer?

A

Barrier to ions and water-soluble compounds

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22
Q

What are the main types of Membrane Proteins?

A

a. Integral proteins - within the membrane
b. Peripheral proteins - bound to inner or outer surface of membrane
c. Anchoring proteins (stabilizers) - attaches to inside or outside structures
d. Recognition proteins (identifiers) - label cells as normal or abnormal
e. Enzymes - catalyze reactions
f. Receptor proteins - bind and respond to ligands (ions, hormones)
g. Carrier proteins - transport specific solutes through membrane

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23
Q

What are channels?

A

What regulates water flow and solutes passing through membranes

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24
Q

What are Gated Channels?

A

Channels that open and close to regulate passage of substances

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25
Q

What are Membrane Carbohydrates and what are the main types?

A
  • Extend outside cell membranes to form sticky “sugar coat” glycocalyx
    Ex. Proteoglycans, glycoproteins, glycolipids
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26
Q

What are the main functions of the Glycocalyx?

A
  • Lubrication and protection
  • Anchoring and locomotion
  • Specificity in binding (function as receptors)
  • Recognition (immune response)
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27
Q

What is the Cytosol and what is it composed of?

A
  • Intracellular fluid
  • Contains dissolved materials (nutrients, ions, proteins, and waste products)
  • High protein and potassium levels
  • Low carbohydrate, lipid, amino acid, and sodium levels
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28
Q

What are the main types and characteristics of Nonmembranous Organelles?

A
  • No membrane
  • Direct contact with cytosol
    Ex. Cytoskeleton, centrioles, ribosomes, proteasomes, microvilli, cilia, and flagella
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29
Q

What are the main types and characteristics of Membranous Organelles?

A
  • Organelles isolated from cytosol by a plasma membrane

Ex. Endoplasmic reticulum (ER), the Golgi apparatus, lysosomes, peroxisomes, and mitochondria

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30
Q

What are Inclusions?

A

Masses of insoluble materials in cells (some consist of glycogen or lipid droplets)

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31
Q

What are the main components that make up the Cytoskeleton?

A

a. Microfilaments
b. Intermediate filaments
c. Microtubules

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32
Q

What are Microfilaments and what are its main functions?

A

Thin filaments composed of the protein actin

  • Provides mechanical strength
  • Interacts with other proteins to adjust consistency of cytosol
  • Interacts with thick filaments of myosin for muscle contraction
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33
Q

What are the main functions of Intermediate Filaments?

A
  • Durable
  • Strengthen the cell and maintain its shape
  • Stabilize position of organelles
  • Stabilize cell position
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34
Q

What are Microtubules?

A

Large, hollow tubes of tubulin proteins

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35
Q

What are the main functions of Microtubules?

A
  • Attach to centrosome
  • Strengthen cell and anchor organelles
  • Change cell shape
  • Move organelles within the cell with the help of motor proteins (kinesin and dynein)
  • Form spindle apparatus to distribute chromosomes
  • Form centrioles and cilia of organelles
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36
Q

What are the main functions of Microvilli?

A
  • Increase surface area for absorption

- Attach to cytoskeleton

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37
Q

What is the main function of Centrioles?

A

Forms spindle apparatus during cell division

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38
Q

What is the Centrosome?

A

Cytoplasm next to the nucleus that surrounds centrioles

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39
Q

What is the Cilia and what are its main functions?

A
  • Slender extensions of plasma membrane

- Functions to move fluids across the cell surface

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40
Q

What are the 2 main types of Cilia? What are its functions?

A
  1. Primary cilium
    - Nonmotile
    - Found in variety of cells
    - Senses environmental stimuli
  2. Motile cilia
    - Found on cells lining the respiratory and reproductive tracts
    - The microtubules in the cilia are anchored to a basal body
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41
Q

What are Ribosomes and what are they composed of?

A
  • Organelles that synthesize proteins
  • Composed of small and large ribosomal subunits
  • Contains ribosomal RNA (rRNA)
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42
Q

What are Free Ribosomes and what are its main functions?

A
  • Found in the cytoplasm

- Manufactures proteins that enter cytosol directly

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43
Q

What are Fixed Ribosomes and what are its main functions?

A
  • Attached to the endoplasmic reticulum

- Manufactures proteins that enter ER for packaging

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44
Q

What are Proteasomes?

A

Organelles that contain enzymes (proteases) that dissemble damaged proteins for recycling

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45
Q

What are the 5 main types of membranous organelles?

A
  1. Endoplasmic reticulum (ER)
  2. Golgi apparatus
  3. Lysosomes
  4. Peroxisomes
  5. Mitochondria
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46
Q

The Endoplasmic Reticulum (ER) contains storage chambers known as…

A

Cisternae

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47
Q

What are the main functions of the Endoplasmic Reticulum?

A
  • Synthesis of proteins, carbohydrates, and lipids
  • Storage of synthesized molecules and materials
  • Transport of materials within the ER
  • Detoxification of drugs or toxins
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48
Q

The Smooth Endoplasmic Reticulum Surface _____ contain attached ribosomes.

A

Doesn’t

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49
Q

The Smooth Endoplasmic Reticulum synthesizes what?

A
  • Phospholipids and cholesterol (for membranes)
  • Steroid hormones (for reproductive system)
  • Glycerides (for storage in liver and fat cells)
  • Glycogen (for storage in muscle and liver cells)
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50
Q

The Rough Endoplasmic Reticulum surface _____ contain attached ribosomes.

A

Does

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51
Q

What are the main functions of the Rough Endoplasmic Reticulum?

A
  • Active in protein and glycoprotein synthesis
  • Folds proteins into secondary and tertiary structures
  • Encloses products in transport vesicles for delivery to golgi apparatus
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52
Q

What are the main functions of the Golgi Apparatus (complex)?

A
  • Modifies and packages secretions (such as hormones or enzymes, for release from cell)
  • Adds or removes carbohydrates to or from proteins
  • Renews or modifies the plasma membrane
  • Packages special enzymes within vesicles (lysosomes) for use in the cytoplasm
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53
Q

What are Lysosomes and what are its main functions?

A
  • Powerful enzyme-containing vesicles produced by the golgi apparatus
  • Functions to destroy bacteria, break down molecules, and recycle damaged organelles
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54
Q

What is the difference between Primary Lysosomes and Secondary Lysosomes?

A

a. Primary lysosomes
- Contain inactive enzymes
b. Secondary lysosomes
- Formed when primary lysosomes fuse with damaged organelles and enzymes are activated

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55
Q

What is the process of Autolysis? Explain the process…

A

Self destruction of damaged or inactive cells

  • Lysosome membranes break down
  • Digestive enzymes released
  • Cell is destroyed
  • Cellular materials are recycled
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56
Q

What are Peroxisomes?

A

Small, enzyme-containing vesicles produced by division of existing peroxisomes

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57
Q

What are the main functions of Peroxisomes?

A
  • Break down organic compounds such as fatty acids
  • Produce the free radical hydrogen peroxide (H2O2)
  • Catalase converts H2O2 to oxygen and water
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58
Q

The Mitochondria takes ________ energy from ______ to produce the ______ molecule _____.

A

Chemical; food (glucose); energy; ATP

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59
Q

What are the main types of Mitochondrial Energy Productions?

A

a. Glycolysis
b. Citric acid cycle
c. Electron transport chain
d. Aerobic metabolism

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60
Q

Explain the process of Glycolysis…

A
  • Converts glucose to pyruvic acid (in cytosol)

- Mitochondria absorbs pyruvate molecules

61
Q

Explain the process of the Citric Acid Cycle (Krebs Cycle)…

A
  • Occurs in mitochondrial matrix

- Breaks down pyruvate

62
Q

Explain the process of Aerobic Metabolism (Cellular Respiration)…

A
  • Mitochondria uses oxygen to break down food and produce ATP
  • Produces 95% of ATP needed to keep a cell alive
  • Glucose + oxygen + ADP –> carbon dioxide + water + ATP
63
Q

Explain Membrane Flow (Membrane Trafficking)…

A
  • A continuous exchange of membrane segments by vesicles
  • Involves all membranous organelles (except mitochondria)
  • Allows adaptation and change
64
Q

What is the Nucleus?

A
  • Largest organelle

- The cell’s control center

65
Q

What are the main components that make up the Nucleus?

A

a. Nuclear envelope - double membrane around the nucleus
b. Perinuclear space
- Space between the two layers of the nuclear envelope
c. Nuclear pores - communication passages in the nuclear envelope

66
Q

What is the Nuclear Matrix?

A

Structure that supports filaments in the nucleoplasm

67
Q

What is Nucleoli?

A

Nuclear organelles that are made of RNA, enzymes, and histones and synthesize rRNA and assemble ribosomal subunits

68
Q

What are Nucleosomes?

A

DNA coiled around histones and loosely coiled into chromatin in non-dividing cells

69
Q

What is the Genetic Code?

A

Chemical language of DNA instructions (sequence of bases; A, T, C, G)

70
Q

What is a Gene?

A

DNA instructions for one protein (the functional unit of heredity)

71
Q

What is the process of Protein Synthesis?

A

Assembling of functional polypeptides in the cytoplasm

72
Q

What is the process of Gene Activation?

A

Uncoiling DNA and temporarily removing histones

73
Q

What is the process of Transcription?

A
  • Synthesis of RNA from DNA template (all RNA, including messenger RNA (mrRNA), is formed through transcription of DNA)
74
Q

What components make up the two strands of DNA?

A

a. Coding strand - specifies the sequence of amino acids in polypeptides
b. Template strand - used for mRNA production

75
Q

Explain the process of Transcription…

A
  1. RNA polymerase binding
  2. RNA polymerase nucleotide linking
    - Begins at “start” signal in promoter region
    - Reads DNA code
    - Binds nucleotides to form mRNA in three-base sequences known as codons
  3. Detachment of mRNA
    - Enzyme and mRNA strand detach from DNA at “stop” signal
76
Q

Explain the process of RNA Processing…

A
  • mRNA is “edited” before leaving nucleus
  • Noncoding sequences (introns) are removed
  • Coding segments (exons) are spliced together
77
Q

Explain the process of Translation…

A
  • After leaving nucleus, mRNA binds to ribosomal subunits in cytoplasm
  • Each mRNA codon translates to one amino acid
  • Amino acids are delivered by transfer RNA
  • A tRNA anticodon binds to complementary mRNA codon
  • Enzymes join amino acids with peptide bonds
  • At stop codon, components separate
78
Q

The plasma (cell) membrane is a barrier, but what must get in and what must get out?

A
  • Nutrients must get in

- Products and wastes must get out

79
Q

Explain what Permeability is and the different types of Permeability…

A
  • Permeability determines what moves in and out of a cell
    Impermeable - lets nothing in or out
    Freely Permeable - lets anything pass
    Selectively Permeable - restricts movement
80
Q

What type of Permeability does a Plasma Membrane have?

A
  • Selectively permeable
  • Allows dome materials to move freely
  • Restricts other materials based on their
    a. Size
    b. Electrical charge
    c. Molecular shape
    d. Lipid solubility
81
Q

Transport through plasma membrane can involve what type of processes?

A

a. Passive processes (no energy required)

b. Active processes (requiring energy)

82
Q

Identify which of these processes are active or passive:

a. Diffusion and osmosis
b. Carrier-mediated transport
c. Vesicular transport

A

a. Diffusion and osmosis (passive)
b. Carrier-mediated transport (passive OR active)
c. Vesicular transport (active)

83
Q

Explain the process of Diffusion…

A

Net movement of a substance from area of higher concentration to area of lower concentration (ions and molecules are constantly in motion; molecules in solution move randomly)

84
Q

What is a Concentration Gradient?

A

The difference between high and low concentrations of a substance

85
Q

What are the different factors influencing Diffusion?

A

a. Distance the particles have to move
b. Ion and molecule size
- Smaller = faster diffusion
c. Temperature
- More heat = faster diffusion
d. Concentration gradient
- Steeper gradient = faster diffusion
e. Electrical forces
- Opposites attract, like charges repel

86
Q

What type of substances utilize Simple Diffusion?

A
    • Lipid soluble compounds (alcohols, fatty acids, and steroids)
  • Dissolved gases (oxygen and carbon dioxide)
  • Water molecules
87
Q

What type of substances utilizes Channel-Mediated Diffusion?

A
  • Water soluble compounds and ions

* **Affected by size, charge, and interaction with channel walls

88
Q

Explain the process of Osmosis…

A
  • Diffusion of water across a selectively permeable membrane

- Water molecules diffuse across a membrane toward the solution with more solutes

89
Q

What is Osmotic Pressure?

A

The force with which pure water moves into a solution as a result of solute concentration

90
Q

What is Hydrostatic Pressure?

A

Pressure needed to block osmosis

91
Q

Explain why Osmosis occurs more rapidly than solute diffusion…

A
  • Because water can cross a membrane through abundant water channels (aquaporins)
  • Aquaporins outnumber solute channels
92
Q

Define Osmolarity (Osmotic Concentration)

A

The total solute concentration in a solution

93
Q

What is Tonicity?

A
  • Describes how a solution affects cells

- Depends on the nature of the solutes

94
Q

What is an Isotonic Solution?

A
  • Same tension solution

- Does not cause osmotic flow

95
Q

What is a Hypotonic Solution?

A
  • Below tension solution

- Lower solute concentration than the cell

96
Q

What is a Hypertonic Solution?

A
  • Above tension solution

- Higher solute concentration than the cell

97
Q

What happens to a cell in an Isotonic Solution?

A

Stays the same size and shape

98
Q

What happens to a cell in a Hypotonic Solution?

A
  • Gains water

- May rupture (hemolysis)

99
Q

What happens to a cell in a Hypertonic Solution?

A

Loses water and shrinks (crenation)

100
Q

What is Carrier-Mediated Transport?

A

Proteins transport ions or organic substrates across plasma membrane

101
Q

Explain Carrier-Mediated Transport specificity…

A

One transport protein, one set of substrates

102
Q

The saturation limits of Carrier-Mediated Transport depends on…

A

Availability of transport proteins and substrates

103
Q

What is Symport Carrier-Mediated Transport?

A

When two substances move in the same direction at the same time

104
Q

What is Antiport Carrier-Mediated Transport?

A

When one substance moves in while another moves out

105
Q

Explain the process of Facilitated Diffusion…

A
  • Passive transport
  • Carrier proteins transport molecules too large to fit through channel proteins (ex. glucose, amino acids)
  • Molecule binds to receptor site on carrier protein
  • Protein changes shape, molecule passes through
  • Receptor site is specific to certain molecules
106
Q

Explain the process of Active Transport…

A
  • Active transport proteins move substrates against concentration gradients
  • Requires energy, such as ATP
107
Q

What do Ion Pumps move?

A

Move ions (ex. Na+, K+, Ca2+, Mg2+)

108
Q

What do Exchange Pumps move?

A

Two ions in opposite directions at the same time

109
Q

Explain the process of Primary Active Transport…

A

Pumping solutes against a concentration gradient using ATP

110
Q

What do Sodium-Potassium Exchange Pumps move?

A

One ATP powers the movement of three sodium ions (Na+) out and two potassium ions (K+) in

111
Q

Explain the process of Secondary Active Transport…

A
  • ATP is required to establish a concentration gradient of one substance in order to passively transport another
    Ex. Na+ concentration gradient drives glucose transport into cells; ATP is used to pump Na+ back out
112
Q

What is Vesicular Transport?

A

Bulk transport; when materials move into or out of a cell in vesicles

113
Q

What is Endocytosis?

A

The importation of extracellular materials packaged within vesicles, which requires ATP

114
Q

What are the main types of Endocytosis?

A
  1. Receptor-mediated endocytosis
  2. Pinocytosis
  3. Phagocytosis
115
Q

Explain the process of Receptor-Mediated Endocytosis…

A
  • Receptors (glycoproteins) bind target molecules (ligands)
  • Receptors and their ligands migrate to clathrin-coated pits of plasma membrane to enter cell
  • Some receptors are associated with membrane lipids and small indentations called caveolae
116
Q

What is Exocytosis?

A

Granules or droplets are released from the cell as a vesicle fuses to plasma membrane

117
Q

What is a Potential Difference?

A

When positive and negative charges are separated, a potential difference is created

118
Q

What is a Membrane Potential?

A

Unequal charge across the plasma membrane

119
Q

Resting Membrane Potential ranges from…

A

-10 mV to -100 mV depending on cell type

120
Q

What is the process of Cell Division?

A
  • A form of cellular reproduction
  • A single cell divides to produce two daughter cells
  • At the end of a cell’s life span, it undergoes genetically controlled death called apoptosis
121
Q

What is Interphase of the cell life cycle?

A
  • Nondividing period in which somatic cells spend the majority of their lives (performs normal functions and if necessary prepares for cell division)
  • Divided into different phases…
    a. G0
    b. G1
    c. S
    d. G2
122
Q

Explain what occurs during the G1 stage of Interphase…

A
  • Cell makes enough mitochondria, cytoskeletal elements, endoplasmic reticulum, ribosomes, golgi apparatus membranes and cytosol for 2 functional cells
  • Centriole replication begins and commonly cont, until G2
  • Preparation for mitosis occurs as cells perform their normal functions
123
Q

Explain what occurs during the S stage of Interphase…

A
  • When activities of G1 have completed, cell enters S phase
  • Cell duplicates its chromosomes
  • This involves DNA replication and synthesis of histones and other proteins in nucleus
124
Q

Explain what occurs during the G2 stage of Interphase…

A
124
Q

Explain what occurs during the G2 stage of Interphase…

A
  • Once DNA replication has ended

- G2 phase devoted to last minute protein synthesis and to the completion of centriole replication

125
Q

Explain what occurs during the G0 stage of Interphase…

A
  • Cell is not preparing for division
  • Performing all other functions appropriate for that particular cell type
  • Some mature cells (ex. skeletal muscle cells and most neurons) remain in G0 indefinitely and never divide
  • In contrast, stem cells, which divide repeatedly with very brief interphase periods, never enter G0
126
Q

What is the function of DNA Polymerase?

A
  • Promotes bonding between the nitrogenous bases of the DNA strand and complementary DNA nucleotides dissolved in the nucleoplasm
  • Links the nucleotides by covalent bonds
127
Q

What are the stages that make up the M Phase?

A
  • Mitosis

- Cytokinesis

128
Q

Explain what occurs during the Mitosis Stage of the M Phase…

A
  • Duplication of chromosomes in the nucleus and their separation into two identical sets
  • A continuous process consisting of several stages: prophase, metaphase, anaphase, and telophase
129
Q

Explain what occurs during the Cytokinesis Stage of the M Phase…

A
  • Division of the cytoplasm

- Produces two daughter cells

130
Q

Explain what occurs during the Early Prophase Stage…

A
  • Begins when chromatin condenses and chromosomes become visible as single structures
  • Array of microtubules (spindle fibers) extend between centriole pairs
  • Smaller microtubules (astral rays) radiate into cytoplasm
131
Q

Explain what occurs during the Late Prophase Stage…

A
  • Resulting from DNA replication during S phase, 2 copies of each chromosome now exist
  • Each copy (chromatid) is connected to its duplicated copy at single point (centromere)
  • Kinetochores are the protein bound areas of the centromere; they attach to spindle fibers forming chromosomal microtubules
132
Q

Explain what occurs during the Metaphase Stage…

A
  • Begins as chromatids move to narrow central zone called metaphase plate
  • Ends when all chromatids are aligned in plane of metaphase plate
133
Q

Explain what occurs during the Anaphase Stage…

A
  • Begins when centromere of each chromatid pair splits and chromatids separate
  • The 2 daughter chromosomes are pulled toward opposite ends of cell along the chromosomal microtubules
134
Q

Explain what occurs during the Telophase Stage…

A
  • Each new cell prepares to return to interphase state
  • Nuclear membranes re-form, nuclei enlarge, and chromosomes gradually uncoil
  • This stage marks end of mitosis
135
Q

Explain what occurs during the Cytokinesis Stage…

A
  • Division of the cytoplasm into 2 daughter cells
  • Usually begins with the formation of cleavage furrow and continues throughout telophase
  • Completion of cytokinesis marks the end of cell division
136
Q

Explain what Mitotic Rate is…

A
  • Rate of cell division

- Slower mitotic rate means LONGER cell life

137
Q

Cell Division _____ require energy (ATP).

A

Does

138
Q

Cell Division can be stimulated by…

A

a. Internal factors
- M-phase promoting factor
- MPF
b. Extracellular chemical factors
- Growth factors

139
Q

Cell Division can be inhibited by…

A

a. Repressor genes
- Faulty repressors cause cancers
b. Worn out telomeres
- Terminal DNA segments

140
Q

What is a Tumor (Neoplasm)?

A

A mass produced by abnormal cell growth and division

141
Q

What is the difference between a benign tumor and a malignant tumor?

A

a. Benign tumor
- Contained; not life threatening unless enlarges
b. Malignant tumor
- Spreads into surrounding tissues (invasion)

142
Q

Cancer results from what?

A
  • Abnormal proliferation of cells

- Caused by mutations in genes involved with cell growth

143
Q

Modified genes are called…

A

Oncogenes

144
Q

What are Mutagens?

A

Agents that cause mutations

145
Q

What are Carcinogens?

A

Cancer causing agents (includes many mutagens)

146
Q

What is Metastasis?

A

The spread of cancer to other areas (begins with invasion of tissues surrounding tumor)

147
Q

T/F All cells contain the same chromosomes and genes

A

True

148
Q

How do cells undergo cellular differentiation and why?

A
  • Undergo cellular differentiation by turning off genes not needed by that cell
  • Allows for formation of different types of cells like liver cells, fat cells, and neurons

Anatomy and Physiology Lecture (12 decks)

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