Biology Section Flashcards
1
Q
tight junctions: function
A
act as a permeability barrier – preventing transport of protein molecules from lumenal side of cell to basolateral side of cell also act to hold neighboring cells together
2
Q
desmosomes: function
A
hold cells together
3
Q
Gap Junctions: function
A
provides a mean for water–soluble molecules to pass from the cytoplasm of one cell to the cytoplasm of another cell
4
Q
type of cells in epidermal region of skin
A
stratified epilthelial cells
5
Q
Cells that secrete many of the proteins that make up structural connective tissue
A
fibroblasts
6
Q
Structural proteins secreted by fibroblasts
A
collagen, elastin, reticulin
7
Q
collagen: features and function
A
–triple stranded, insoluble, fibrous protein –highly cross–linked –quite strong and flexible
8
Q
reticulin: features and function
A
–thin fiber –not as highly coiled as collagen –found in spleen and lymph nodes
9
Q
elastin: features and function
A
–highly cross–linked protein –associated with organs that require elasticity (lungs, skin, blood vessels, etc.)
10
Q
Cartilage: –type of tissue –cell type –where found
A
–connective tissue –special type of fibroblast = chondrocyte –fond in places where stress is put on bodies
11
Q
bone: –made up of
A
–1/3 organic materials (such as collagen) –2/3 inorganic materials (calcium carbonate, calcium phosphate, etc.)
12
Q
bone: –what secretes collagen in the bone matrix
A
–Specialized fibroblast cells called osteoblasts
13
Q
_______ lend(s) flexibility to bones, while ________ lend(s) rigidity
A
–Collagen for flexibility –inorganic cystals for rigidity
14
Q
Mast Cells
A
–Release histamines in response to an allergic reaction, infection, or injury
15
Q
Effect of histamines
A
Cause an increase in blood flow to blood vessels in the affected region
16
Q
Where are mast cells found
A
Respiratory tract, GI tract, etc.
17
Q
Two types of cells that make up nervous system
A
(1) Nerve cells (neurons) (2) Support cells (glial cells)
18
Q
Major anatomical features of a neuron
A
(1) Cell Body = integrates info (2) Dendrites = Receive info + Transmit info towards cell body (3) Axon = conducts info away from the cell body
19
Q
End of a neuron = ______
A
synaptic bulb
20
Q
Concentration of Na+ and K+ inside vs outside cell
A
IN CELL: small Na+ LARGE K+ OUTSIDE OF CELL: LARGE Na+ small K+
21
Q
Concentration of Cl– and HCO3– inside vs. outside of cells
A
Cl– = lower inside cell HCO3– = usually lower inside cell also
22
Q
Typically voltage inside cell (compared to outside). Explain
A
Typically ~ –80mV –negative because of leaky K+ channels – so K+ diffuses outside of cell (down its gradient)
23
Q
What is the ATPase Pump
A
Pumps Na+ out of the cell and K+ into the cell (against both of their gradients)
24
Q
Nernst Equation
A
Vio = 2/3 (RT)/(ZF) x log([K+]o/[K+]i)
25
Steps to generation of an action potential:
(1) Stimulus: causes a transient increase in membrane permeability to Na+ (2) Depolarization: caused by Na+ influx (3) Flood of Na+ into cell: will occur if cell is depolarized enough (4) Action Potential: generated by the flood of Na+
26
High level steps pre and post action potential
(1) Stimulus (2) Depolarization –\> Action Potential (3) Repolarization: K+ channels open and K+ exits the cell (4) Hyperpolarization: Massive amounts of K+ exit the cell (5) Refractory Period: Na+ channels are temporarily inactive (neuron can't generate another action potential
27
The generation of an action potential is an ________ phenomenon, and will always have \_\_\_\_\_\_\_
All–or–nothing Will always have the same magnitude
28
Two factors leading to faster and further action potentials
(1) Myelenation (2) Larger neuronal cross sectional area
29
Glial cells myelenate ________ (part of neuron)
Axons
30
Area on axons where there is no myelin
Nodes of Ranvier
31
Type of glial cell that myelenates the CNS
Oligodendrocytes
32
Type of glial cell that myelenates the PNS
Schwann Cells
33
Nerve impulse in myelenated neurons
Referred to as saltatory conduction "Jumps" from node to node along the axons – ions can only enter at the Nodes of Ranvier
34
How does an action potential spread through neuromuscular junction
(1) Action potential reaches synaptic terminal (2) Triggers Ca2+ channels to open – Ca2+ flows into synaptic terminal region (3) Synaptic vesicles fuse with presynaptic membrane – causing release of neurotransmitter (often ACh) into synaptic cleft (4) Neurotransmitter diffuses through the cleft – binding to the postsynaptic membrane receptors (5) Causing receptors to change conformation to a channel – allowing Na+ to flow in (6) Na+ flux in leads to depolarization and action potential
35
Excitatory vs. Inhibitory Post Synaptic Potentials
If lets in Na+ === excitatory If lets in Cl– or K+ ==== inhibitory
36
How is ACh (Acetylcholine) broken down
the enzyme acetylcholinesterase, which is bound to the postsynaptic membrane, hydrolyzes ACh into acetate and choline –Acetate and choline are transported back into the presynaptic terminal where they are used in the synthesis of Ach
37
Attach bone to muscle
tendon
38
attach bone to bone
ligaments
39
Muscles are made up of multinucleated \_\_\_\_\_\_\_, which are made up of \_\_\_\_\_\_\_\_, which are made up of \_\_\_\_\_\_\_\_.
Multinucleated Muscle Cells (aka Muscle Fibers) –––\> Myofibrils ––––\> Sarcomeres
40
The _______ contain the contractile units of the muscle
Myofibrils
41
the contractile units of the muscle = \_\_\_\_\_
sarcomeres
42
Sarcomeres are bound by the \_\_\_\_\_\_\_\_.
Z–line
43
Where there is only actin
I–band
44
the ______ contains all of the myosin
A–Band
45
the ______ is the region in the center of the A–Band, and it only contains myosin.
H Zone
46
Thin contractile protein of sarcomeres = _____ Thick contractile protein = \_\_\_\_\_\_\_
thin = actin thick = myosin
47
\_\_\_\_\_ are arranged towards the center of the sarcomere (and not attached to the Z–Line)
Myosin
48
Where are myosin heads located
In the terminal regions of myosin
49
Actin filament is composed of a protein subunit called _______ (because the shape is \_\_\_\_\_).
G Actin (G for globular because the shape is roughly spherical)
50
How can actin filaments grow
by the addition of G actin to the ends of already existing filament
51
Each actin is composed of \_\_\_\_\_\_\_\_\_\_
2 rows of G actin monomers wound around each other to form a helix
52
High level summary of muscle contraction steps
(1) ATP is bound to myosin head (so myosin and actin aren't bound) = relaxed state (2) ATP is hydorlyzed to ADP + Pi ––– myosin undergoes conformational change (3) High energy Myosin–ADP–Pi complex binds to actin (4) Causes release of ADP + Pi from myosin heads –– causing another conformation change of myosin ––––\> Actin moves relative to myosin Called the POWER STROKE (5) ATP binds myosin – causing myosin to release actin
53
What causes myosin to be able to bind actin
Tropomyosin is on actin, and covers the myosin binding sites Ca2+ binds to troponin – which is attached to troponin, and causes a conformational change in tropomyosin, uncovering the myosin binding sites on actin
54
Relationship between action potentials and muscle contraction
Action potential travels down T–Tubules, causing release of Ca2+ from sarcoplasmic reticulum into the cytosol (where it can bind to troponin, allowing myosin to bind to actin, allowing for the power stroke)
55
How Ca2+ in cytosol returns to sarcoplasmic reticulum
through Ca2+ –ATPase Pump
56
Eqn for generation of ATP in aerobic conditions (from glucose)
Glucose –––––\> CO2 + H20 + 36ATP (slower)
57
Eqn for generation of ATP in anaerobic conditions (from glucose)
Glucose ––––––\> Lactate + 2ATP (faster)
58
During anaerobic conditions, [lactate] begins to \_\_\_\_\_\_, which will case the ph to \_\_\_\_\_\_\_. Effects of this.
[lactate] increases, and pH decreases –some enzymes can no longer function outside of pH range – halting glycolysis and ATP yield
59
a grouping of nerve cells = a \_\_\_\_\_\_\_
ganglian
60
CNS = ______ PNS = \_\_\_\_\_\_
CNS = brain + spinal cord PNS = all nerves extending from the spinal cord
61
3 divisions of the vertebrate brain
(1) Forebrain (2) Midbrain (3) Hindbrain
62
3 Main subdivisions of the forebrain
(1) Cerebrum (2) Thalamus (3) Hypothalamus
63
The _______ has 2 hemispheres (right and left) which are joined by the \_\_\_\_\_\_.
Cerebrum (of the Forebrain); joined by the corpus callosum
64
The Lobes of the cerebrum (and what they are associated with)
(1) Frontal = movement and personality (2) Parietal = touch and stretch sensation (3) Temporal = Hearing (4) Occipital = Vision
65
Outermost layer of the cerebrum = the \_\_\_\_\_\_
cerebral cortex
66
The cerebral cortex consists of _______ and \_\_\_\_\_\_. Locations of both
–gray matter = nerve cell bodies + their dendrites–white matter = myelinated axons of nerve cells White matter is central, gray is on outside"
67
Location: White and Gray matter in Cerebrum and Spinal cord
in Cerebrum: White = Central; Gray = Outside in Spinal Cord: White = Outside; Gray = Central
68
3 important landmarks in cerebral cortex
(1) Central Sulcus = groove; separates frontal + parietal lobes (2) Motor Cortex = Controls movement of individual muscles (3) Sensory Cortex = Detects sensations in various parts of the body
69
Sensory Homonucleus
Schematic model of human being mapped out on the sensory cortex – showing which neurons register sensations from different body parts
70
Thalamus: function
relay station for visual and audio info
71
hypothalamus: function
concerned with visceral activities of the body
72
pituitary gland: function
master endocrine gland –receives info from hypothalamus and sends out info to regulate the body
73
brainstem: different features
\*detects movement and can direct the head and eyes towards it –Midbrain: also senses pleasure + pain –Cerebellum: Resposible for the bulk of regulation + coordination of muscular activity –Pons and Medulla: coordinate visceral activities –Reticular Formation: brainstem core; alerts the brain + inhibits motor and sensory impulses that can induce sleep
74
Muscle that elicits extension (when it contracts) = ______ Muscle that elicits bending/flexing = \_\_\_\_\_"
Extensor Flexor
75
the nerve pathway involved in a reflex action including at its simplest a sensory nerve and a motor nerve with a synapse between = \_\_\_\_\_\_\_. Can be mono or poly–synaptic"
Reflex Arc –monosynaptic or polysnaptic reflex arcs –can include interneurons (transmit impulses between other neurons)"
76
efferent vs afferent divisions of the PNS
Efferent (AWAY from CNS): Carry nerve impulses: CNS –––––\> Muscle Afferent (TO CNS): Carry nerve impulses: Sensory stimuli ––––\> CNS
77
The Autonomic Nervous system is part of the ______ division of the PNS
Efferent
78
One part of the _________ Nervous System is the ___________ Nervous System, which can be divided into the _________ and _________ Systems.
Peripheral –––\> Autonomic ––––\> Sympathetic + Parasympathetic
79
Where do nerve fibers leave from in the Autonomic Nervous System?
Sacral portion of spinal cord; and midbrain and medulla
80
Key functions of Parasympathetic vs Sympathetic Nervous Systems
Parasympathetic = rest and digest Sympathetic = fight or flight
81
The preganglionic nerve fibers vs. the postganglionic nerve fibers. When long and short.
In parasympathetic system: pre = long post = short In sympathetic system: pre = short post = long
82
What neurotransmitters do different nerve fibers of the parasympathetic and sympathetic systems release?
Parasympathetic System: Pre = ACh Pos = ACh Sympathetic System: Pre = ACh Post = Norepinephrine
83
Cholingeric Nerve Fibers
Release ACh (Acetylcholine)
84
Most prominent nerve in parasympathetic division
Vagus Nerve ~75% of all neurons in the parasympathetic division are found in the vagus nerve –innervates many organs
85
Sympathetic Division has nerve fibers branching off from
Thoracic and Lumbar regions of the spinal cord
86
How adrenal medulla functions
(1) Preganglionic nerve fibers from thoracic region of spinal cord (sympathetic division) synapse directly with nerve fibers on the adrenal medulla (i.e., there are no postganglionic nerve fibers) (2) Adrenal medulla is stimulated and releases norepinephrine and epinephrine directly into the bloodstream (thus are hormones) –––\> thus it is an endocrine gland \*causes increase in HR and pupils to dilate
87
somatic nervous system
Part of the PNS related to voluntary movements
88
How somatic nervous system functions
(1) Nerve fibers leave CNS and don't synapse until they reach their effector organ (2) ACh is released (3) Innervating Skeletal Muscle (4) Can be excitatory or inhibitory
89
Some types of sensory receptors (and what they sense)
(1) Mechanoreceptors: Pressure; hearing; balance; blood pressure (2) Nocireceptors: Pain (3) Thermoreceptors: cold and warmth (4) Chemoreceptors: Taste, smell, O2, CO2, glucose levels, etc. (5) Photoreceptors (of retina): Photons
90
How sensory receptors receive, transduce, transmit, info
(1) receptor receives sensory info (2) Stimulus received changes membrane potential of receptor (transduction) (3) If potential changes enough, an action potential results
91
Adaptation of Sensory Neurons (and which cells adapt a lot and which don't)
Over time, frequency of action potentials diminishes, so can no longer feel the sensation –Pressure Receptors adapt a lot, and pain do not
92
Receptive Field
Axonal branches of a single neuron and the many receptors that the branches end at
93
Three Neurons involved in sensory pathways
(1) First Order Neurons: Recetive field –––\> Spinal cord. Synapses with – (2) Second Order Neurons: Ascend spinal cord to thalamus. (3) Third Order Neurons: Reach specific region of somatosensory cortex
94
Receptor found on postganglionic parasympathetic neuron targets (aka effector organ neurons)
Muscarinic Receptors
95
Receptor found on preganglionic parasympathetic neuron targets (aka the postganglionic nerurons)
Nicotinic Cholingeric Receptors
96
Receptor found on postganglionic sympathetic neuron targets (aka effector organ neurons)
Adrenergic Receptors
97
Receptor found on preganglionic sympathetic neuron targets (aka the postganglionic nerurons)
Nicotinic Cholingeric Receptors
98
Nerve Fibers that release norephinephrine (or epenephrine = adrenaline)
Adrenergic nerve fibers
99
Receptor found on cells of the adrenal medulla
Nicotinic Cholingeric Receptors
100
receptor found on endplates of motor neurons
nicotinic cholingeric receptors
101
How to number Carbons
Carbon of the Carboxyl Group (COO) = #1
102
autosomal dominant genetic defect
if you inherit the gene from one parent you can get the disease
103
Vocab: attenuate" = \_\_\_\_\_"
to reduce
104
Essential Amino Acids in Humans (and mnemonic device)
Valine Methionine Histidine Leucine Phenylalanine Threonine Isoleucine Lycine Tryptophan = Very Many Happy Little Pigs Take Iced Lemon Tea
105
What does it mean for a circulatory system to be closed?
Blood doesn't freely mix with body flood
106
High level summary: blood flow starting after returning from tissues
"(1) Right Atrium (2) Right Ventricle (3) Pulmonary Artery (4) Pulmonary Veins (5) Left Atrium (6) Left Ventricle (7) Aorta ––\> Arteries ––\> Arterioles ––\> Capillaries\*(where nutrient exchange occurs) (8) Venules ––\> Veins ––\> Superior + Inferior Vena Cava \*\*and then back to right atrium"
107
Arteries = _________ heart Veins = ___________ heart (direction)
Arteries = AWAY from heart Veins = TO heart
108
Blood pressure measurement steps
(1) Inflate cuff so pressure \> Arterial systolic pressure ---\> artery collapses (stops blood flow) (2) When cuff pressure \< Arterial systolic pressure, blood will flow again = "systolic pressure" -will be turbulant flow (b/c high pressure + narrow opening) (3) As relax cuff, turbulant flow will eventually disappear - instead will have laminar (smooth) flow -this is the "diastolic pressure"
109
Arteries are composed of what tissue types? Why?
Thick walls composed of smooth muscle and connective tissue (with elastin and collagen) –helps maintain pressure (and not be too high or low)
110
Endothelial cells
Blood Vessel Epithelial cells
111
Damage to endothelial cells = ________ Lots of damage results in \_\_\_\_\_\_\_\_\_\_
damage = atherosclerosis lots of damage = get hardening of arteries = arteriosclerosis
112
Arteries are important because they represent a major area of _______ in the cardiovascular system.
RESISTANCE (thus the strong walls)
113
Sphincter at the entrance to capillary bed; what it is composed of and what it does
Precapillary Sphincter –composed of smooth muscle which helps to regulate blood flow to the area
114
What allows blood to flow in only one direction in a vein?
Specialized Valves in veins = prevent backflow
115
Varicose beins
valve problem in veins; get backflow which increases vein pressure
116
Valve between right atrium and right ventricle
Right Atroventricular Valve aka Tricuspid Valve
117
Valve between Right Ventricle and Pulmonary Artery
Pulmonary Valve
118
Valve between left atrium and left ventricle
Left Atroventricular Valve aka Mitral Valve
119
Valve between left ventricle and aorta
Aortic Valve
120
What happens once ventricles are filled with blood
–they contract and the AV valves close (preventing backflow) = "lub"
121
What happens as blood flows out of the pulmonary artery and aorta
Pulmonary and Aortic Valves close = "dub"
122
What causes the "lub" and "dub" heart noises?"
"lub" = AV valves closing "dub" = Pulmonary and Aortic valves closing
123
Why don't the AV valves invert
b/c of tendinous cords = chordae tendinae which hold them in place
124
What is the major pacemaker of the heart
Sinoatrial Node (SA Node)
125
What happens if the SA node is damaged
AV node will take over and slow the heart rate to ~40bpm
126
Where impulse travels from SA Node
SA Node ––\> Atroventricular Node (AV Node) ––\> Bundle of His, which causes ventricles to contract and eject blood
127
Negative Feedback loop when blood pressure is too low
Stimulus: Decrease in arteriol pressure –which means less stretch on arteries––\> ––baroreceptors sense this and send impulses to medulla and brainstem––\> –––medulla activates sympathetic nervous system––\> ––––Impulses sent (via sympathetic system) cause norepinephrine (or epinephrine) release at SA Node––\> –––––SA Node increases heart rate ––––––Increasing heart contractions –––––––Increasing Blood pressure
128
Cardiac Output
=Blood Pumped Per Minute –by each of the ventricles in Liters/Min Cardiac Output = (Stroke Volume)\*(Heart Rate) liters/min = (liters/beat)\*(beat/min)
129
Eqn for Poiseuille's Law
Flow = ΔPπ(R^4)/(8ηL) = (P1–P2)\*π(R^4)/(8ηL) where η = viscosity ΔP = Pressure drop from 2 ends of tube R = Radius of tube L = length of tube
130
4 key takeaways from Poiseuille's Law
(1) Flow is proportional to R^4 –––\> VERY dependent on radius! (2) Flow is proportional to the inverse of L –––\> short tubes = faster flow (3) Flow is proportional to the inverse of η –––\> High viscosity = slower flow (4) ΔP is what drives blood flow in the cardiovascular system
131
How does temperature affect diffusion
Increase Temp ––\> Increased Energy ––\> Increased Diffusion
132
Fick's Law Eqn
J = –(D)(A)(ΔC/Δx) = –DA(Cout – Cin)/Δx Where J = net rate of diffusion (usually mol/s) ΔC/Δx = concentration gradient
133
Concentration of pure water
55.5 mol/L
134
What happens to the concentration of water when you add solutes? Why?
It will decrease (from 55.5 mol/L) because solute is taking up space water was taking up
135
How does the concentration of water change when adding one mol of glucose vs one mol of NaCl. Why?
One mol of NaCl will displace twice as much water – because it will ionize to Na+ and Cl– meaning that it will take up twice as much space, and decrease water's concentration by twice as much
136
What is an osmol
1 mol that doesn't ionize
137
1 M NaCl soln = ______ osmol/L
2 osmol/L
138
Osmolarity
The total solute concentration of a solution
139
What is osmotic pressure (aka πosm) –and explain in terms of the semipermeable membrane experiment
The amount of pressure that stops osmosis –osmosis will occur until the added pressure (on the side of the tank with the added protein, due to the added volume) offsets the change in concentration (since water molecules will flow to the side with the higher osmolarity – the right side, through the semipermeable membrane)
140
Hydrostatic Pressure
the difference in H2O levels from one side of the semipermeable membrane to the other, Δh, which is a direct measurement of the osmotic pressure
141
Purpose of the lymphatic system
Collects excess fluid that leaks into the interstitial space from capillaries and returns it back to the circulatory system via the vena cava
142
Purpose of lymph nodes
filter out foreign particles that could cause disease
143
What happens if a lymph node is blocked? –How does this occur after heart surgery?
Edema results = increase in interstitial fluid –after heart surgery: heart can't pump blood fast enough –\> backup in veins –\> backup in lymphatic system ––– as a result, edema occurs – particularly in swollen ankles and legs (fluid pools there due to gravity)
144
Hydrostatic pressure in the capillaries forces fluid from \_\_\_\_\_\_\_\_––\> _________ ––\> \_\_\_\_\_\_\_\_\_
Capillaries –––\> Interstitial Space –––\> Lymphatic Capillaries
145
Blood clotting occurs via a ______ which allows for \_\_\_\_\_\_\_.
Cascade Process allows for amplification
146
The two different pathways in blood clotting
Intrinsic Route - due to contact with some abnormal surface (e.g., "internal" damage to the blood vessel) Extrinsic Route - due to trauma of the tissue (e.g., blood vessel breaks and goes outside of the blood vessel or "external")
147
Many of the factors involved in blood clotting are called \_\_\_\_\_\_\_\_\_
serine proteases
148
Staring with Factor Xa, describe the high level cascade leading to blood clotting
(1) In presence of Factor Xa (as well as Va, an auxiliary factor); prothrombin (which ws converted from preprothrombin –––\> thrombin (2) Thrombin converts: fibrinogen –––\> fibrin (3) Fibrin forms the blood clot (needs transglutimase in order to be converted to crossed–linked fibrin clot in order to do the clotting)
149
How is preprothrombonin converted to prothrombin
A Carboxylase enzyme (carboxylates Glu residues) –the enzyme requires Vitamin K+ and HCO3–
150
Why is preprothrombin converted to prothrombin?
B/c Prothrombin is a good chelating agent = it has a high affinity for Ca2+ (which is essential for blood clotting)
151
How do blood platelets bind the factor necessary in the blood clotting?
The negative charge on phospholipid heads on blood platelets allows γ–carboxyglutamate residues on prothrombin to bind via Ca2+ –Factor Xa also has γ–carboxyglutamate residues and also binds. Xa then cuts prothrombin releasing thrombin
152
Why fibrinogen must be converted to fibrin
fibrinogen is large and soluble with a large negative charge (which will cause repulsion) –must release some of the negative charges (as fibrinopeptides) to get to insoluble fibrin, which has a +5 central charge (in addition to still negative charged ends) –––\> now can have aggregation of fibrin monomers with one another (leading to fibrin clot)
153
Soft clot vs Hard clot (in blood clotting)
Soft Clot = initial fibrin clot Hard Clot = there is a cross–linking via the enzyme transglutaminase (to get cross–linked fibrin clot)
154
Once a damaged area has been repaired via blood clotting, what happens
Plasmin (a serine protease) hydrolyzes regions in fibrin clot to dissolve it into smaller fragments (removing clot) –Tissue Plasminogen Activator (TPA) converts plasminogen to plasmin
155
What is dicoumarol
Vitamin K antagonist – causes abnormal prothrombin that doesn't bind to Ca2+
156
What is warafarin
Vitamin K antagonist – causes hemorrhaging in rats and mice
157
High Level summary of how air passes down respiratory tract
(1) Oral cavity (2) Pharynx (3) Larynx (4) Trachea (5) 2 Bronchi (one to each lunch) ––– \> Lungs: (6) Many bronchioles (7) MANY MANY alveoli
158
respiration
process by which oxygen is brought to the cells of tissues and CO2 is removed as a waste product
159
Composition of an alveolus 2 factors leading to fast diffusion
Each alveolus consists of a single layer of epithelial cells juxtaposed to a very thin basement membrane 2 factors of fast diffusion –epithelial layer and endothelial layer of capillaries are barely separated –have millions of alveoli (large surface area)
160
Atmospheric Pressure at sea level = \_\_\_\_\_\_
760 atm
161
Rough makeup of Atmospheric Pressure (by molecule)
78% N2 21% O2 0.3% CO2 0.7% H2O
162
How to calculate partial pressures
Multiple the % of the pressure a molecule/gas makes up by the total pressure (partial pressures are INDEPENDENT of one another)
163
Why does the Partial Pressure of O2 decrease at altitude?
TOTAL pressure decreases (but O2 is still 21% of the total)
164
What does it mean if a gas is at equilibrium with a liquid
The # molecules dissolving into the liquid is the same as the # of molecules leaving the liquid ––\> the partial pressure of the molecule/gas is the same in the gas phase as in the liquid
165
Total pressure of any gas is proportional to \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.
Its concentration of molecules in the air.
166
What is the total pressure of air acting on membranes of epithelial cells in the alveoli of the lungs equal to?
The sum of the total partial pressures of all gases in the air
167
Structure of respiratory tract – how foreign objects leave the tract
Epithelial cells line lumen of passageways to bronchioles and have cilia which beat upwards. –also have mucus secreating glands. \*\*cilia beat moving mucus and foreign objects trapped in mucus upward to oral cavity where its swallowed by reflex.
168
How does smoking affect respiratory system
–it decreases cilia activity while also decreasing the body's defense against lung infections by bacteria
169
Type of tissue that lines upper and lower respiratory tract (and how that impacts function)
Upper passageways = maintain openings by cartilage rings Lower down (bronchioles, for ex) = smooth muscle instead
170
diaphragm –type of tissue –location
Skeletal muscle separating thoracic cavity and abdomen
171
Pleural membranes involved in breathing What is in between them
Visceral Pleura = covers lungs Parietal Pleura = adheres to diaphagm in between = intrapleural space = contains watery fluid
172
How does breathing occur (beginning with muscle contraction)
Rib Cage muscles contract and pull rib cage up+out while diaphragm muscles pull the diaphragm downward –––\> thus enlarging thoracic cavity ––\> causes pleural membranes to move via suction – expanding lungs, creating subatomic pressure in alveoli ––\> allowing for inspiration –when stop contracting, tissue returns to normal length and air in alveoli is forced out = expiration"
173
What would happen to the lungs without connection to visceral pleura?
lungs would collapse
174
What allows for diffusion of Oxygen to capillaries and CO2 to alveoli?
Pressure differences between capillaries and alveoli
175
The greater the pressure differences, the more diffusion there is of O2 from ________ –\> __________ CO2 from _________ –\> \_\_\_\_\_\_\_\_\_
O2: blood in capillaries –\> tissue cells CO2: tissue cells –\> blood in capillaries
176
How is oxygen carried in the blood
Mostly through hemoglobin; a little through diffusion
177
hemoglobin
transport protein in red blood cells – transports O2
178
Structure of hemoglobin
quaternary structure –has 4 polypeptide subunits ––each has a heme group with a Fe2+ in the center ––in total can bind 4 O2
179
What happens to O2 solubility in blood due to hemoglobin?
When hemoglobin takes up O2, more O2 can leave gas phase in alveoli and enter the blood – thus increasing O2 solubility in blood
180
How saturated is hemoglobin in the capillaries? –How much of this O2 does hemoglobin give up to tissues?
98% saturated with O2 in capillaries –only gives up ~25% to tissues
181
what happens to the O2 dissociation curve of hemoglobin when pH is decreased? –one example of when this cold occur
Curve shifts down and right –ex: exercise
182
–what happens to the O2 dissociation curve of hemoglobin when 2,3–BPG (a byproduct of glycolysis) binds to hemoglobin? –one example of when this cold occur
Curve shifts down and right –ex: O2 deprivation
183
What happens when hemoglobin O2 dissociation curve shifts?
Shifts down and right = causes hemoglobin to release more O2 to tissues at the same PO2
184
How is CO2 carried in the blood?
(1) 70% – in HCO3– form (2) 20% – on hemoglobin (3) 10% – dissociated in plasma and red blood cells
185
How does CO2/HCO3– conversion occur in tissues
(1) CO2 diffuses into RBC where it is converted to H2CO3 via carbonic anhydrase (2) H2CO3 ionizes to H+ and HCO3– (3) HCO3– diffuses into blood plasma and is carried to capillaries of lungs by circulatory system
186
How does CO2/HCO3– conversion occur in the lungs?
(1) HCO3– diffuses into RBC where it combines with H+ and becomes H2CO3 (2) H2CO3 is converted to CO2 via carbonic anhydrase (3) CO2 diffuses into blood plasma and then diffuses into capillaries and then to the alveoli
187
What part of the brain coordinates breathing
Brainstem – particularly medulla and pons
188
How do medulla and pons coordinate breathing
Δ[H+] and Δ[CO2] –––\> affect chemosensitive areas of medulla and Δ[O2] is sensed by chemoreceptors of cartoid arteries and aorta arch–––\> –transmit signals to brainstem \*nerve impulses from medulla and pons cause respiratory muscles to contract
189
bronchioles are innervated by ___________ nerves
Parasympathetic
190
What is asthma
hypersensitivity to airborne antigens –––\> spasm and constrict smooth muscles of bronchioles
191
The total cross sectional area of ________ is the largest of all types of vessels in the cardiovascular system
all the capillaries
192
\_\_\_\_\_\_\_ regulate the flow of blood throughout the body
areterioles
193
Blood pressure has the highest velocity and the highest pressure when \_\_\_\_\_\_\_\_\_\_
After exiting the left ventricle
194
\_\_\_\_\_\_\_\_\_\_\_\_\_\_ measures turbulant flow.
Reynold's Number. Usually turbulant when Re \> 2000
195
Reynold's Number Equation
Re = vdp / n where v = velocity d = vessel diameter p = density n = viscosity
196
Which walls are stronger: arterial walls or vein walls Which are more distensible
ARTERIAL walls are stronger thus VEIN walls are more distensible
197
Which walls are less distensible – systemic artery walls or pulmonary artery walls? Why?
Systemic Artery Walls B/c they are under more pressure and thus less distensible
198
what is the effect of blood centrifugation?
Separates plasma and Red Blood Cells –with a buffy coat in between (made up of WBC and platelets)
199
What is the ames test?
Ames test for mutagens: Mix suspected mutagen (a chemical) with bacteria (as well as, for example, liver extract), incubate, and see if many mutated colonies appear. If they do, the suspected mutagen is in fact a mutagen.
200
How many rings do purines and pyrimidines have?
Purines have 2 rings Pyrimidines have 1 ring
201
What about the SA node allows for it to be a pacemaker
Gradual depolarization – called pacemaker potential – which brings the membrane potential to threshold, when an action potential can occur
202
Alkane and alkene chemical formulas
Alkane = CnH2n+2 Alkene = CnH2n
203
Phosphorylation = the addition of \_\_\_\_\_\_\_
Phosphate: PO4 3–
204
Acetylation = the addition of
Acetate: C2H3O2–
205
Carboxyl Group (chemical formula)
COOH
206
The heart rate is controlled by \_\_\_\_
Medulla Oblongata
