Biology Midterm 1 Flashcards
1
Q
Anatomy
A
Studies the structure of body parts and their relationship to one another
2
Q
Physiology
A
Concerns the function of the body; how the body parts work and carry out their life-sustaining activities
3
Q
Gross (macroscopic) anatomy
A
The study of large body structures visible to the naked eye
4
Q
Regional anatomy
A
Anatomy of a particular region is studied at the same time
5
Q
Systemic anatomy
A
Anatomy of a particular system is studied at the same time
6
Q
Surface anatomy
A
The study of internal structures as they relate to the overlying skin surface
7
Q
Microscopic anatomy
A
Studies structures too small to be seen with the naked eye
8
Q
Cytology
A
Studies the cells of the body
9
Q
Histology
A
The study of tissues
10
Q
Renal physiology
A
Kidney function and urine production system
11
Q
Neurophysiology
A
Explains the workings of the nervous system
12
Q
Cardiovascular physiology
A
Examines the operation of the heart and blood vessels
13
Q
Principle of complementarity of structure and function
A
What a structure can do depends on its specific form. Function always reflects structure
14
Q
Chemical level
A
Atoms combine to form molecules
15
Q
Cellular levels
A
Molecules combine to form cellular organelles; The smallest living organisms are cells. In multi cellular organisms calls have unique functions
16
Q
Tissue level
A
Tissues are groups of similar cells that have a common function
17
Q
Organ level
A
Organs are discrete structures composed of at least two tissues; very specialized functions
18
Q
Organ system level
A
Organs that work together to accomplish a purpose in an organism
19
Q
Organismal level
A
The sum total of all structural levels working together to keep us alive
20
Q
Integumentary system
A
The very outer layer of the body providing a protective barrier for internal organs. (Synthesizes vitamin D and has pressure/pain receptors and oil/sweat glands)
21
Q
Skeletal system
A
The framework of the body supporting tissues and protecting organs. Blood cells formed with bones; bones store minerals
22
Q
Muscular system
A
Contracting muscles allows for movement; maintains body posture and produces heat
23
Q
Lymphatic system
A
Collects fluid outside of the circulatory system in order to return it to the blood stream. Houses white blood cells involved in the body’s defensive immune system
24
Q
Respiratory system
A
Oxygenates blood and removes carbon dioxide
25
Digestive system
Breaks down food in order to absorb the nutrients for body function (waste eliminated as feces)
26
Nervous system
Responds to internal and external stimuli through fast acting response
27
Endocrine system
Regulates processes including growth, reproduction, and metabolism through glands that secrete hormones
28
Cardiovascular system
System composed of the heart and blood vessels pumping blood that transports oxygen, nutrients, carbon dioxide, wastes, ect.
29
Urinary system
Eliminates waste from the body and regulates water, electrolytes, and the balance of acid and base in the body
30
Reproductive system
Functions for the production of offspring; sexual reproduction results in male sperm fertilizing the female egg resulting in an embryo that the female body develops and births as a human newborn
31
Epidermis
Composed of epithelial cells, it is the outermost layer of the body for protection of the internal layers
32
Dermis
Tough layer of connective tissue underneath the epidermis for nutrient diffusion and connection
33
Stratum Basale (Basal Layer)
Deepest epidermal layer involved in the continual renewal of cells
34
Stratum Spinosum (Prickly layer)
Several layers thic that serve to resist tension in the cell
35
Stratum Granulosum (Granular layer)
Consists of one to five cell layers in which keratinization occurs; forms keratin and reduces water loss
36
Subcutaneous tissue
Tissue that connects the skin to underlying structures
37
Mucosa
Innermost layer of the digestive system
- Secretes mucus, enzymes, and hormones
- Absorbs the end products of digestion
- Protects against disease
38
Submucosa
Just external to the mucosa; areolar connective tissue and rich supply of blood vessels
- Enables the stomach to regain its normal shape (after storing a large meal)
39
Muscularis Externa
Consists of smooth muscle cells; responsible for segmentation and peristalsis, controls food passage. Made up of 2 layers:
* Inner circular layer
* Outer longitudal layer
40
Serosa
Outermost layer of intraperitoneal organs formed of connective tissue for structural support and connection
41
Mucous
Found on the epithelial cells facing the lumen and protects digestive organs from enzymes
42
Superior
Higher
43
Inferior
Lower
44
Anterior
Front
45
Posterior
Back
46
Medial
Toward the middle
47
Lateral
Away from the middle
48
Proximal
Closer
49
Distal
farther
50
Superficial
On the surface
51
Deep
Under the surface
52
Dorsal
Above (usually in an animal context)
53
Ventral
Below (usually in an animal context)
54
Parietal
Outer layer
55
Visceral
Inner layer
56
Abdominal
Stomach area
57
Pelvic
Underbelly
58
Coxal
Hip
59
Pubic
Genital
60
Otic
Ear
61
Frontal
Forehead
62
Orbital
Eye
63
Nasal
Nose
64
Cervical
Neck
65
Thoracic
Chest
66
Lumbar
Lower back
67
Sacral
Lower back in between the two hips
68
Axillary
Side of chest
69
Popliteal
Back of knee
70
Femoral
Thigh
71
Plantar
Bottom of foot
72
Sagittal plane
Vertical plane that divides the body into right/left
73
Midsagittal (median) plane
Sagittal plane that lies directly in the middle of the body
74
Frontal (coronal) plane
Vertical plane that divides the body into anterior and posterior parts
75
Transverse (cross) plane
Horizontal plane dividing the body into superior and inferior parts
76
Oblique plane
Cuts made diagonally between horizontal and vertical planes
77
Thoracic cavity
Houses the heart and lungs; surrounded by ribs and muscles
78
Abdominopelvic cavity
Includes abdominal and pelvic cavities
79
Cranial cavity
Houses the brain
80
Pleural cavity
Houses one lung each
81
Pericardial cavity
Houses just the heart
82
Mediastinum
Cavity around the pericardial cavity, and the remaining thoracic organs (esophagus, trachea, and others)
83
Abdominopelvic cavity
Has two parts; The abdominal cavity and the pelvic cavity
84
Abdominal cavity
Contains the stomach
85
Dorsal body cavity
Protects the fragile nervous system organs and is made up of the cranial cavity and the spinal (vertebral) cavity
86
Spinal (vertebral) cavity
Runs within the bony vertebral column and encloses the delicate spinal cord.
87
Ventral body cavity
More anterior and larger of the closed body cavities
Major subdivisions: Thoracic cavity and abdominopelvic cavity
Houses internal organs (viscera)
88
Viscera
Organs in the body cavity
89
Pelvic cavity
Lies in the pelvis and contains the urinary bladder, some reproductive organs, and the rectum
90
Serosa (serous membrane)
Thin, double-layered membrane covering the walls of the ventral body cavity and outer surfaces of the organs
91
Perietal serosa
The part of the membrane lining the cavity walls
92
Visceral serosa
Membrane that folds in on itself covering the organs in the cavity
93
Serous fluid
Thin layer of lubricating fluid secreted by the serosal membranes
Allows organs to slide without friction across the cavity walls as they carry out their routine functions
94
Right upper quadrant (RUQ)
Right upper quadrant of the abdominopelvic cavity from the subject's point of view (top left when viewed by observer)
95
Right lower quadrant (RLQ)
Right lower quadrant of the abdominopelvic cavity from the subject's point of view (bottom left when viewed by observer)
96
Left upper quadrant (LUQ)
Left upper quadrant of the abdominopelvic cavity from the subject's point of view (top right when viewed by observer)
97
Left lower quadrant (LLQ)
Left lower quadrant of the abdominopelvic cavity from the subject's point of view (bottom right when viewed by observer)
98
Umbilical region
Centermost region deep to and surrounding the umbilicus (navel)
99
Epistatic region
Located superior to the umbilical region (upper belly)
100
Pubic (hypogastric) region
Located inferior to the umbillical region (lower belly)
101
Right and left inguinal (iliac) regions
Located lateral to the hypogastric region (superior part of the hip bone)
102
Right and left lateral (lumbar) regions
Lie lateral to the umbilical region (loin)
103
Right and left hypochondriac regions
Lie lateral to the epigastric region and deep to the rips (cartilage)
104
Oral cavity
The mouth: contains teeth and tongue
105
Digestive cavity
Continuous with oral cavity
| Opens to the body exterior at the anus
106
Nasal cavity
Located within and posterior to the nose
| Part of the respiratory system passageways
107
Orbital cavities
Cavities in the skull that house the eyes and present them in an anterior position
108
Middle ear cavities
Lie just medial to the eardrums
| Contain tiny bones that transmit sound vibrations to the hearing receptors in the inner ears
109
Synovial cavities
Joint cavities
Enclosed within fibrous capsules that surround freely movable joints of the body (elbow and knee)
Membranes lining these cavities secrete lubricating fluid to reduce friction
110
Matter
Anything that occupies space and mass
111
Energy
The capacity to do work
112
Kinetic energy
Energy in action
113
Potential energy
Stored energy that is inactive but has potential to do work
114
Chemical energy
Form of energy stored in the bonds of chemical substances
115
Electrical energy
Results from the movement of charged particles
116
Mechanical energy
Energy directly involved in moving matter
117
Radiant energy (electromagnetic radiation)
Energy that travels in waves
118
Elements
Unique substances that cannot be broken down into simpler substances by ordinary chemical methods
119
Periodic table
List of known elements and helps to explain the properties of each element
120
Atoms
Building blocks of elements
121
Atomic symbol
One or two letter chemical shorthand for an element
122
Nucleus
Contains protons and neutrons tightly bound together
123
Protons (p+)
Subatomic particles that bear a positive electrical charge
124
Neutrons (n0)
Neutral subatomic particle
125
1 atomic mass unit (amu)
The mass of protons/neutrons
126
Electrons (e-)
Subatomic particles that bear a negative charge equal to the positive charge of the proton
1/2000 the mass of a proton
127
Planetary model of the atom
Simplified model of atomic structure (electrons moving around nucleus in fixed, circular orbits)
128
Orbitals
Regions around the nucleus in which a given electron or electron pair is likely to be found most of the time
129
Orbital model
Uses orbitals to model the atom (more useful for predicting chemical behaviour of atoms)
130
Atomic number
Equal to the number of protons in its nucleus
131
Mass number
Sum of the masses in an atom's protons and neutrons
132
Isotopes
Structural variations of elements - Differ in the number of neutrons
133
Atomic weight
An average of the weights of all the isotopes of an element taking into account their relative abundance in nature
134
Radioisotopes
Heavier isotopes of elements that are unstable so their atoms may decompose spontaneously into more stable forms; this process of atomic decay is radioactivity
135
Compound
When two or more different kinds of atoms bind
136
Molecule
A combination of two or more atoms held together by chemical bonds
137
Mixtures
Substances composed of two or more components physically intermixed (solutions, colloids, and suspensions)
138
Solutions
Homogeneous mixtures of components that may be gases, liquids, or solids
139
Molarity
Moles per liter (M)
| Concentration measurement
140
Percent
Parts per 100 parts
141
Mole
The atomic or molecular weight of any molecule in grams
142
Molecular weight
Sum of the atomic weights in a molecule
143
Avogadro's number
One mole of any substance always contains 6.02 x 10^23 solute particles
144
Colloids
Emulsions; heterogeneous mixtures (composition is dissimilar in different areas of the mixture
145
Sol-gel transformations
To change reversibly from a fluid (sol) state to a more solid (gel) state. Some colloids do this (gelatin)
146
Suspensions
Heterogeneous mixtures with large, often visible solutes that tend to settles out
147
Chemical bonds
An energy relationship between the electrons of the reacting atoms (made or broken in less than a trillionth of a second)
148
Electron shell
Regions of space that consecutively surround the atomic nucleus
149
Energy level
Same as electron shells; Different electron shells represent different energy levels (electrons are particles with a certain amount of potential energy)
150
Valence shell
An atom's outermost energy level or that portion of it containing the electrons that are chemically reactive
151
Octet rule
Rule of eights
Except for shell 1, which is full when it has 2 electrons, atoms tend to interact in such a way they end up having 8 electrons in their valence shell
152
Ions
When electrons are transferred from one atom to another and the precise balance of + and - charges is lost resulting in charged particles
153
Ionic bond
A chemical bond between atoms formed by the transfer of one or more electrons from one atom to the other
154
Anion
An atom with a net negative charge
155
Cation
An atom with a net positive charge
156
Crystals
Large arrays of cations and anions held together by ionic bonds
157
Covalent bond
Molecules in which electrons are shared where the shared electrons occupy a single orbital common to both atoms
158
Nonpolar molecules
Molecules that are covalently bonded and electrically balanced
159
Polar molecules
Molecules that have an unequal electron pair sharing resulting in poles of opposite charges
160
Electronegativity
Atoms with 6 or 7 valence shell electrons that are electron-hungry and attract electrons very strongly
161
Electropositive
Electron-attracting ability of an atom is so low that they usually lose their valence shell electrons to other atoms
162
Dipole
A molecule with two poles of charge (polar molecule)
163
Hydrogen bonds
Weak bonds - more like attractions
When a hydrogen atom (covalently bonded to an electronegative atom eg nitrogen/oxygen) is attracted to another electron-hungry atom so that a 'bridge' forms between them
164
Chemical reaction
When chemical bonds are formed, rearranged, or broken
165
Reactants
The number and kinds of interacting substances
166
Products
The chemical composition of the result of the reaction
167
Molecular formula
The way molecules are represented by its atomic symbol and number of atoms making up the molecule
168
Synthesis (Combination reaction)
When atoms or molecules combine to form a larger, more complex molecule
169
Decomposition reaction
When a molecule is broken down into smaller molecules or its constituent atoms
170
Catabolic
Degradative processes in body cells
171
Exchange reactions (displacement)
Involve both synthesis and decomposition
| Bonds are both made and broken; parts of the reactant molecules change partners producing different product molecules
172
Oxidation-reduction reactions (redox)
Decomposition reactions where food fuels are broken down for energy (electrons are exchanged between reactants)
173
Oxidized
The electron donor in an oxidation reduction reaction is oxidized
174
Reduced
The reactant taking up the transferred electrons is reduced
175
Exergonic reactions
Reactions that release energy
176
Endergonic reactions
Reactions that contain more potential energy in their chemical bonds than did the reactants
177
Chemical equilibrium
For each molecule of product (AB) formed, one product molecule breaks down, releasing the reactants A and B
178
Catalysts
Substances that increase the rate of chemical reactions without themselves becoming chemically changed or part of the product
179
Universal solvent
water
180
Biochemistry
The study of chemical composition and reactions of living matter
181
Organic compounds
Compounds containing carbon and are made by living things (covalently bonded often large)
182
Inorganic compounds
Compounds that lack carbon
183
Hydration layers
Layers of water molecules around large charged molecules such as proteins sheilding them from the effects of other charged substances
184
Salt
An ionic compound containing cations other than H+ and anions other than the hydroxyl ion (OH-)
185
Electrolytes
Substances that conduct an electrical current in solution
186
Acids
Substances that releases hydrogen ions (H+) in detectable amounts
Also sour and reactive
187
Proton donors
When dissolved in water acids release hydrogen ions (protons) and anions
A hydrogen ion is just a hydrogen nucleus which is a single proton
188
Bases
Substances that take up hydrogen ions (H+) in detectable amounts
Also bitter and slippery
189
(OH-)
Hydroxyl ions
190
(H+)
Hydrogen ions
191
(HCO3-)
Bicarbonate ion
192
(NH3)
Ammonia
193
pH units
Concentration of acidity measurement
194
Buffers
Resist abrupt and large swings in the pH of body fluids by releasing hydrogen ions (acting as acids) when the pH begins to rise and by binding hydrogen ions (acting as bases) when the pH drops
195
Strong acids
Acids that dissociate completely and irreversibly
196
Weak acids
Acids do not dissociate completely
197
Strong bases
Bases that dissociate easily in water and quickly tie up (H+)
198
Weak bases
Bases that ionize incompletely and reversibly accepeting relatively few protons
199
Bicarbonate buffer system
In this buffer system the weak acid (carbonic acid (H2CO3) dissociates reversibly, releasing its corresponding weak base, bicarbonate ions (HCO3-) and protons (H+)
200
Electroneutral
Never loses or gains electrons (carbon)
201
Macromolecules
Large complex molecules containing thousands of atoms
202
Polymers
Chainlike molecules made of many smaller, identical or similar subunits
203
Monomers
Small subunits of polymers
204
Dehydration synthesis
Monomers are joined by removal of OH from one monomer and removal of H from the other at the site of bond formation resulting in the release of a water molecule as a covalent bond forms
205
Hydrolysis
A water molecule is added to each bond that is broken thereby releasing its building blocks
Monomers are released by the addition of a water molecule, adding OH to one monomer and H to the other
206
Carbohydrates
A group of molecules that includes sugars and starches (represent 1-2% of cell mass)
Contain carbon, hydrogen, and oxygen (hydrogen atoms generally occur in the same 2:1 ratio of water; hydrated carbon)
207
Monosaccharides
'Simple sugars'
| Single-chain or single-ring structures containing from three to seven carbon atoms
208
Isomers
Have the same molecular formula but atoms are arranged differently giving different chemical properties
209
Polysaccharides
Polymers of simple sugars linked together by dehydration synthesis
210
Lipids
Insoluble in water but dissolve readily in other lipids and other organic solvents
211
Triglycerides
Commonly known as fats or oils
Large molecules (often consisting of hundreds of atoms) providing the body's most efficient and compact form of stored energy; when oxidized they yield large amounts of energy
Made up of fatty acids and glycerol in a 3:1 ratio
212
Fatty acids
Linear chains of carbon and hydrogen atoms (hydrocarbon chains) with an organic acid group (COOH) at one end
213
Glycerol
A modified simple sugar (a sugar alcohol)
214
Saturated fats
Fatty acid chains with only single covalent bonds between carbon atoms
215
Unsaturated fats (monounsaturated/polyunsaturated)
Fatty acids that contain one or more double bonds between carbon atoms
216
Trans fats
Oils that have been solidified by addition of H atoms at sites of carbon double bonds (margarine)
217
Phospholipids
Modified triglycerides; they have two, rather than three, fatty acid chains. The third chain is replaced by a phosphate group (PO4) with an attached nitrogen0contianing group
218
Hydrophobic
Water fearing
| Hydrophobic molecules only interact with other nonpolar molecules
219
Hydrophilic
Water loving
220
Steroids
Flat molecules made of four interlocking hydrocarbon rings
| Fat soluble and contain little oxygen
221
Cholesterol
Basis for all steroids formed in the body. Found in cell membranes and is the raw material for synthesis of vitamin D, steroid hormones, and bile salts
222
Protein
Basic structural material of the body
223
Amino acids
The building blocks of proteins
224
Peptide bond
Bond between proteins joined together by dehydration synthesis with the acid end of one amino acid linked to the amine end of the next
225
Polypeptide
Ten or more united amino acids
226
Alpha helix
A secondary protein structure in which the primary protein chain coils
227
Beta sheet
Primary polypeptide chains do not coild, but are linked side by side by hydrogen bonds to form a pleated ribbonlike structure
228
Fibrous (structural) proteins
Form long strands and exhibit at least secondary structure but often third and quaternary structure
Insoluble in water and very stable
229
Globular (functional) proteins
Compact, spherical proteins that have at least tertiary structure
Water soluble chemically active molecules
230
Denatured
When hydrogen bonds begin to break (pH drop or temperature rise) and the proteins unfold and lose their specific three-dimensional shape
231
Enzymes
Globular proteins that act as biological catalysts
232
Active sites
Presence of specific arrangements of atoms where catalytic activity occurs
233
Apoenzyme
Protein portion of a functional enzyme (holoenzyme)
234
Cofactor
Other part of functional enzyme (holoenzyme)
| May be an ion out of a metal element or an organic molecule
235
Coenzyme
A cofactor derived from vitamins (especially B-complex)
236
Substrate
A substance on which an enzyme acts
237
Activation energy
Energy required to be absorbed to prime a reaction
238
Nucleic acids
Composed of carbon, oxygen, hydrogen, nitrogen, and phosphorus, are the largest molecules in the body
239
Deoxyribonucleic acid
DNA - Genetic material
Found in the nucleus
- Replicates
- Provides basic instructions for building every protein in the body
240
Ribonucleic acid
RNA - Located chiefly outside the nucleus
| Carries out orders for protein synthesis issued by DNA
241
Adenine / Guanine
Purine nitrogen bases that are large and two-ring
242
Cytosine / Thymine / Uracil
Pyrimidine nitrogen bases that are small and single-ring
243
Double helix
DNA structure - Coiled molecule of two strands
244
Adenosine triphosphate (ATP)
Primary energy-transferring molecule in cells and provides a form of energy that is immediately usable by all body cells
245
Cells
Structural units of all living things
246
Cell theory
Cell is the smallest unit of life
All organisms are made of one or more cells
Cells only arise from other cells
247
Extracellular materials
Substances contributing to body mass that are found outside the cells
248
Extracellular fluid (ECF)
Includes interstitial fluid, blood plasma, and cerebrospinal fluid
Dissolves and transports substances in the body
249
Interstitial fluid
Fluid in tissues that bathes all of our cells
250
Extracellular matrix
The most abundant extracellular material
251
Plasma membrane
Separates two of the body's major fluid compartments - the intracellular fluid inside the cells and the extracellular fluid outside the cells
252
Intracellular fluid
Fluid within the cells
253
Fluid mosaic model
Depicts the plasma membrane as an exceedingly thin (7-10 nm) structure composed of a double layer, or bilayer, of lipid molecules with protein molecules 'plugged into' or dispersed in it
254
Integral proteins
Firmly inserted into the lipid bilayer
255
Peripheral proteins
Not embedded in the lipid bilayer
256
Glycolipids
Lipids with sugars attached
257
Glycoproteins
Proteins with sugars attached
258
Glycocalyx
"Sugar covering" consists of the fuzzy, sticky, carbohydrate-rich area at the cell surface created by the sugars of glycoproteins and glycolipids
259
Tight cell junction
A series of integral protein molecules in the plasma membranes of adjacent cells fuse together
260
Desmosomes
Anchoring junctions - mechanical couplings scattered like rivets along the sides of adjacent cells to prevent their separation
261
Gap junction
Communicating junction between adjacent cells
Adjacent plasma membranes are very close and the cells are connected by hollow cylinders composed of different transmembrane proteins
262
Passive processes
Substances that cross the membrane without any energy input from the cell
263
Active processes
The cell provides metabolic energy (usually ATP) needed to move substances across the membrane
264
Diffusion
The movement of molecules or ions from an area where they are in higher concentration to an area where they are in lower concentration
265
Concentration gradient
Movement from high to low concentration
266
Simple diffusion
Substances that diffuse directly through the lipid bilayer
267
Facilitated diffusion
A passive process in which the transported substance either binds to carrier proteins in the membrane and is ferried across or moves through water filled channel proteins
268
Channels
Transmembrane proteins that transport substances, usually ions or water, through aqueous channels from one side of the membrane to the other
269
Osmosis
The diffusion of a solvent, such as water, through a selectively permeable membrane
270
Aquaporins (AQPs)
Transmembrane proteins that construct water-specific channels that allow single-file diffusion of water molecules
271
Osmolarity
The total concentration of all solute particles in a solution
272
Hydrostatic pressure
The back pressure exerted by water against the cell wall
273
Osmotic pressure
The tendency of water to move into the cell by osmosis
274
Tonicity
The ability of a solution to change the shape (or plasma membrane tension) of cells by altering the cells' internal water volume
275
Isotonic solutions
Have the same concentrations of nonpenetrating solutes as those found in cells
276
Hypertonic solutions
Have a higher concentration of nonpenetrating solutes than seen in the cell
277
Hypotonic solutions
More dilute than concentration that what is in the cell
278
Active transport
Require transport proteins that combine specifically and reversibly with the transported protein
279
Pumps
Transport proteins that uses energy to do work
280
Cotransport protein
Moves more than one substance at a time in a secondary active transport system
281
Primary active transport
Hydrolysis of ATP results in the phosphorylation of the pump (the transport protein is energized by the transfer of a phosphate group of ATP)
282
Sodium-potassium pump
Drives three Na+ out of the cell and pumps two K+ back in
283
Electrochemical gradients
The negatively and positively charged faces of the plasma membrane can help or hinder diffusion of ions driven by a concentration gradient
284
Secondary active transport (cotransport)
Uses a cotransport protein to couple the "downhill" (down the concentration gradient) movement of another solute
285
Symport system
Two transported substances move in the same direction
286
Antiport system
The transported substances "wave to each other" as they cross the membrane in opposite directions
287
Vesicular transport
Fluids containing large particles and macromolecules are transported across cellular membranes inside bubble-like, membranous sacs called vesicles
288
Transcytosis
Moves substances into, across, and out of the cell
289
Vesicular trafficking
Moves substances from one area (or membranous organelle) in the cell to another
290
Endocytosis
Bringing substances into cell
291
Phagocytosis
Cell engulfs another material by surrounding it in cytoplasmic extensions
292
Phagosome
Endocycotic vesicle
293
Amoeboid motion
Cytoplasm flows into temporary extensions that allow them to creep along
294
Pinocytosis
Bit of infolding plasma membrane surrounds a very small volume of extracellular fluid containing dissolved molecules
295
Receptor-mediated endocytosis
Allows cells to concentrate material that is present only in small amounts in the extracellular fluid
296
Exocytosis
Cesicular transport processes that eject substances from the cell interior into the extracellular fluid
297
Membrane potential
Voltage of a membrane able to generate an action potential
298
Resting membrane potential
Ranges from -50 to -90 mV when the cell is at rest (not generating AP)
299
Electrically polarized
Difference of charge on opposite sides of the cell membrane resulting in a charged membrane
300
Cell adhesion molecules (CAMs)
Sticky glycoproteins that anchor themselves to molecules in the extracellular space, 'arms' that migrating cells use to haul themselves past one another, SOS signals attracting white blood cells to an infected area, and mechanical sensors that transmit information about changes in the extracellular matrix
301
Ligand
Chemical messenger
302
G protein-coupled receptors
Exert their effect indirectly through a G protein - regulatory molecule that acts as a middle man to relay to activate (or inactivate) a membrane-ound enzyme or ion channel
303
Second messengers
Intracellular chemical signals which connect plasma membrane events to the internal metabolic machinery of the cell
304
Cyclic AMP
Important second messenger
305
Cytoplasm
The cellular material between the plasma membrane and the nucleus - site of most cellular activities
306
Cytosol
The viscous, semitransparent fluid in which other cytoplasmic elements are suspended
307
Inclusions
Chemical substances that may or may not be present, depending on cell type
308
Organelles
Metabolic machinery of the cell
309
Mitochondria
Power plants of the cell, providing most of the ATP supply
310
Cristae
Protrude into the mitochondria matrix
311
Ribosomes
Sites of protein synthesis
312
Endoplasmic reticulum
An extensive system of interconnected tubes and parallel sacs called cisterns (filled with fluid)
Continuous with outer nuclear membrane
313
Rough ER
Studded with ribosomes
| Proteins assembled on these ribosomes thread their way into the fluid-filled interior of the ER cisterns
314
Smooth ER
Continuous with the rough ER and consists of tubules arranged in a looping network (play no role in protein synthesis), enzymes catalyze reactions involved in metabolizing lipids, synthesizing steroid based hormones, detoxifying drugs, breaking down glycogen, store calcium ions
315
Golgi apparatus
Consists of stacked and flattened membranous sacs
Principal "traffic director" for cellular proteins
Modifies, concentrates, and packages the proteins and lipids made at the rough ER and destined for export from the cell
316
Peroxisomes
Spherical membranous sacs containing a variety of powerful enzymes (oxidases and catalases)
Oxidases detoxify harmful substances
Neutralizes free radicals
317
Free radicals
Highly reactive chemicals with unpaired electrons that scramble the structure of biological molecules
318
Lysosomes
Spherical membranous organelles containing activated hydrolytic (digestive) enzymes
Large, and abundant in phagocytes - can digest almost all kinds of molecules
319
Endomembrane system
A system of organelles that work together mainly to produce, degrade, store, and export biological molecules as well as degrade potentially harmful substances
320
Cytoskeleton
Elaborate network of rods running through the cytosol that acts as the cell's structure (bones)
321
Microfilaments
Semiflexible strands of the protein actin involved in cell motility and changes in cell shape
322
Intermediate filaments
Tough, insoluble protein fibers that resemble woven ropes
Most stable and permanent of cytoskeletal elements and strongly resist tension
Internal cables that resist pulling forces exerted on the cell
323
Microtubules
Hollow tubes made of spherical protein subunits called tubulin
Determine the overal shape of the cell and distribution of cellular organelles
324
Centrosome
Cell center
| Acts as a microtubule organizing center
325
Centrioles
Small, barrel-shaped organelles oriented at right angles to each other
Form the basis for cilia and flagella
326
Centrosome matrix
Made up of centrioles and centrosomes known for generating microtubules and organizing the mitotic spindle in cell division
327
Cilia
Whiplike, motile cellular extensions - moves substances in one direction across cell surfaces
328
Flagella
Cellular extensions susbtantially longer than cilia and propels the cell itself - sperm
329
Basal bodies
Centrioles forming the bases of cilium or flagellum
330
Microvilli
Tiny, finger-like extensions of the plasma membrane that project from an exposed cell surface
Increase plasma membrane surface area tremendously
331
Nucleus
Control center of cells containing genetic material
332
Multinucleate
Cells that have multiple nuclei
333
Anucleate
Cells that cannot reproduce and therefor live in the bloodstream for only three to four months (have no nucleus - blood)
334
Nuclear envelope
Double membrane barrier separated by a fluid filled space
335
Nuclear pores
Form aqueous transport channels regulating entry and exit of molecules in and out of the nucleus
336
Nucleoli
Where ribosomal subunits are assembled - not membrane bound
337
Chromatin
A system of bumpy threads weaving through the nucleoplasm composed of DNA, globular histone proteins (package and regulate DNA), and RNA
338
Nucleosomes
Consist of flattened disc-shaped cores or clusters of eight histone proteins connected
339
Histones
Provide a physical means for packing the very long DNA molecules in a compact, orderly way
340
Chromosomes
Short barlike bodies of chromatin threads
341
Interphase
The period from cell formation to cell division
342
G1 - Gap 1 subphase
Cell is metabolically active, synthesizing proteins rapidly and growing vigorously
343
G0
Cells that permanently stop dividing
344
S phase
DNA is replciated ensuring that the two future cells being created will receive identical copies of the genetic material
345
G2 - GGap 2 subphase
Brief inal phase of interphase as enzymes and other proteins needed for division are synthesized and moved to their proper sites; centriole replication is complete
346
Prophase
Chromatin condenses resulting in visible chromatids
347
Metaphase
Chromosomes align at equatorial plate
348
Anaphase
Centromeres of chromosomes split simultaneously and chromosomes are pulled to opposite ends of the cell by motor proteins of kinetichores
349
Telophase
Chromosomes uncoil to form chromatin
Nuclear membranes form
Nucleoli reappears
Spindle fibers dissapear
350
Cytokinesis
Splitting of the cell membrane by pinching in the middle
