Walker Lectures Flashcards
1
Q
Autotrophs
A
SELF Nutrition
Harvest light or chemical energy and store it in carbon compounds
Exist in an inorganic environment and they manufacture organic compounds
They are primary producers
Example: Maple Tree
2
Q
Heterotrophs
A
OTHER Nutrition
Orgnims must get complex nutrients from the environment
Receive nutrition by eating other organisms
Found at higher trophic levels
Example: Humans
3
Q
Fungi
A
Can be parasitic or predatory
Fungi receives nutrients from dead organic matter
Example: Bread mold
4
Q
Althete’s foot fungus
A
Extends fungal branches (hyphae) into the cells of the foot to absorb nutrients
5
Q
Dactylella dreschsleri
A
Is a fungus that has sticky knobs along the hyphae that can hold nematode worms
Then hyphae penetrate the worm’s body and digestive enzymes are released and extracellular digestion takes place
6
Q
Arthrobotrys dactyloides
A
Is a fungus that makes traps that are used to capture nematode worms
When nematodes enter the traps made by three cells, the cells swell and constrict essentially lashing the worm.
Then hyphae penetrate the worm and extracellular digestion takes place.
7
Q
Phagocytosis
A
Complicated
Tough to get the membrane to fuse
85 DIFFERENT proteins needed
Important in vertebrates (WBC)
We protect ourselves from microbes using phagocytosis
(Streptococcus and pneumonia)
8
Q
Extracellular Digestion
A
Digested food products are phagocytksed directly into the cells that line the gastrovascular cavity AND further digested intracellularly
Wastes are excreted out of the moth
NOTE: ONE opening serves as both the entry and exit sites for food!
9
Q
Digestion in hydra
A
- (Extracellular) Digestive enzymes are released from a gland cell
- Food particles are broken down by enzymes
- (Intercellular) Food particles are engulfed and digested in food vacuoles
10
Q
Cellulose
A
Found in plants
Series of glucose units turned 180
Linkages are hard to hydrolyze
Produced by some microorganisms (Bacteria + Protozoa)
11
Q
Cellulase
A
Produced by some microorganisms (Bacteria + Protozoa)
12
Q
Cecum
A
Developed during the evolution of plant eating animals
It is 15% of a horse’s digestive tract
13
Q
Rabbits
A
Improved by behaviour
Eat night feces
Leave day time faces (Dry + Powdery)
Put through TWICE
14
Q
Oral Cavity
A
Teeth and salivary glands (In humans 3 pairs of major glands and ~600 smaller ones)
SALIVA (Protein is salivary amylase)
- Digests starch
- Depending on cultural heritages you may have more or less genes that encode salivary amylase
15
Q
HCl
A
Acid with pH of 2
16
Q
Pepsin
A
Enzyme
Produced in cells lining the stomach and ONLY in LOW pH 2
Aminoterminal side of try and phe
17
Q
So why don’t the cells in the stomach lining get hydrolyzed by pepsin and damaged by HCl?
A
- Gastric glands in the chief cells lining the stomach produce pepsin in an inactive form, pepsinogen (Inactive enzymes are called Zymogens and pepsin zymogen = pepsinogen)
- Pepsinogen + HCl = Pepsin - Goblet cells that line the stomach produce a viscous mucous layer with a pH of 6
- The parietal cells that produce the HCl don’t accumulate the acid
- It forms in the stomach after secretion (signalled by this) of H+ and Cl- by a peptide hormone (Gastrin)
- H+ and Cl- ultimately are derived from the circulatory system
- HCl acid forms in the stomach lumen
- Cells lining the stomach have particularly resistant membranes
18
Q
Small Intestine
A
Contents of the stomach (Acid chyme) then passes on to the small intestine where there is a large number of digestive enzymes produced by
- Intestinal Glands
- Pancreas
- Liver
19
Q
The Intestinal glands
A
Maltose W/ (Maltase) = Glucose
Some proteases (Hydrolyzes proteins)
20
Q
Pancreas
A
Duct to small intestine
Restores pH to 7
Some proteases W/Trypsin - Hydrolyzes peptides & looks for lys and arg (Carboxyl)
Chymotrypsin = Carboxyl side
21
Q
Liver
A
Releases bile
Bile contains bile salts which aid the digestion and absorption of lipids
Bile is stored and concentrated in the gallbladder
22
Q
Small Intestine Reactions
A
Trypsinogen W/ (Enterokinease) = Trypsin
Chymotrypsinogen W/ (Trypsin) = Chymotrypsin
Proelastase W/ (Trypsin) = Elastase
23
Q
Celiac Disease
A
Gluten storage is wheat and barley
Makes the immune system attack
Pro-gln-pro-leu-pro-tyr-pro-…
- Structure is chinked
Combo of viral infection and this protein allows the digest of gluten
People without with DO NOT digest gluten
24
Q
Endoproteases
A
(Interior of proteins)
Hydrolysis of a peptide bond with a polypeptide
Examples: Pepsin Tryspin Enterkinase Chymotrypsin Elastase
25
Exoproteases
Hydrolysis of TERMINAL peptide bonds
Examples:
Aminopeptidase
Dipeptidase
Carboxpeptidase
26
Absorption
Digested products, vitamins, minerals and water occurs in the small intestine
Assisted by the huge surface area of the small intestine contributed by the villi and microvilli (contains laterals and capillaries)
27
Trypsin
Carboxyl-side of lys and arg
28
Chymotrypsin, Elastase, and Enterkinase
Caboxyl-side
29
Digestion in Insects
Insect digestions = High pH or NO pH
They do not have pepsin because pepsin works at a low pH
Example: Sheep Blow Fly
Example: Tsete Fly
30
Sheep Blow Fly
They attack road kill OR live on sheep fleece
They digest and take protein from fish and the big flies produce protease for the young to digest
31
Excretion
Metabolic waste that are a result of digestion
32
Elimination (feces)
Undigested food
33
Urea Cycle
Is used to get rid of ammonia which is highly toxic
Urea is the product which is less toxic
34
Urea Cycle with Sharks and Rays
They are the ONLY sea animals without this cycle because they use water to get rid of ammonia/ to dilute the toxic molecule
They build urea in their tissues so they becomes isometric or tonic with sea water
35
Bony Fish
SALTWATER fish
They have less solute [con} inside than the wate
Hypotonic - In danger of dehydrating with water lost across the gills therefore they MUST drink lots of water
Excreted. ammonia is diluted with a minimum amount of water = a very concentrated urine
36
Freshwater Fish
Hypertoic compared to water
They produce large amounts of diluted urine to get rid of water
They have specialized gills to help concentrate the salt
37
Liver Cirrhosis
Caused by alcoholism, infectious disease (hepatitis), or fatty liver disease
Damaged liver cannot efficiently carry out the urea cycle SO ammonia just sits there
- Can go into our NS and destroy the electrochemical grad
- Cause neurological problems
- Change in pH
One leading cause of death n middle years of Western countries
38
Urea Cycle in Birds, Reptiles, and Insects
NO urea cycle
They need to save water
Uric acid gets rid of lots of N's with each molecule made (Nontoxic)
39
Why is uric acid the nitrogenous waste for birds?
NO ammonia or urea present because it is too toxic for baby birds
Uric acid is tired in the allantois and is left behind at hatching
Uric acid is MUCH safer for a little chick
40
Lungfish
Fleshy fins allow for movement in mud
They have lungs
They live in water and NO water during the dry season
Water = High ammonia {con}
- Which starts the urea cycle (NO water condition)
41
Salmon
IN Ocean
- Live for 5 years
- Drinking water
- {con} urine
IN Freshwater
- NO drinking
- Gill function changes
- Stops at fish farms to readjust physiology
42
Excretory Organs: Functions
1. Filtration - Acts like a filter to remove water and small solutes from body fluids or blood while leaving behind blood cells, proteins, and other large solutes
2. Reabsorption - Useful material in the filtrate recaptured and returned to blood
3. Secretion - May put additional solutes into the filtrate (Can aid in the elimination of toxins)
43
The Nephron
Functional unit of the kidney in higher vertebrates (mANY nephrons in each kidney)
Composed of:
1. Capillary network in the renal corpuscle (Bowman's capsule + glomerulus) Forms filtrate
2. A long tubule that performs secretion and reabsorption
3. A collecting duct the empties into he central cavity of the kidney
44
Water and Nephron
Water moves very quickly across the nephron membranes which is aided by water pores (Aquaporins)
- Explains why water can diffuse through kidney membrane more quickly than theoretically possible
- Aquaporin family members can also transport other small molecules
45
Aquaporin
At least 13 members of the aquaporin gene family have been cloned in humans and some are expressed in different parts of the kidney
46
P - glycoprotein Pump (permase)
Important for the transport of hydrophobic drugs out of the cell. They have ATP binding sites
Example: Anticancer drugs
47
Bile Salt Export Pump (BSEP)
ATP- dependent bile salt transporter functions in the liver.
Mutations in this gene can lead to cholestasis characterized by poor fat metabolism, dark urine, severe itching, jaundice, liver failure, and death
48
Cystic fibrosis Transmembrane Conductance Regulator Protein (CFTR)
This pump is a chloride transporter found in the lungs, sweat glands, and some cells of the digestive tract.
It has two ATP binding sites and is an active transporter
49
From cells to whole organisms
1. Here WBC moves toward bacteria in preparation for phagocytosis
2. Vertebrates move using skeletal muscles that act on the skeleton
50
Actin
α actin filament or THIN filament
Actin monomers (small circles) polymerized together to make chain
51
Myosin
Myosin filament or THICK filament
Unusual looking protein with a long tail and TWO heads
Heads = Highly active ATP and ADP+Pi
52
α actinic (Minor Proteins)
Anchor of actin filament
53
Capping Protein (Minor Proteins)
Stops from more growth
54
Tropomyosin (Minor Proteins)
Thin dimer
55
Troponin Complex (Minor Proteins)
Has 3 subunits:
1. Binds to Ca+
2. Binds to tropomyosin
3. Binds to actin
56
Other Proteins (Minor Proteins)
Dystrophin - Structural support to muscles
DISEASE: Muscular dystrophin which causes damage to muscle fibres when dystrophin is NOT present
57
Skeletal Muscle Structure (Big Picture)
A muscle is a grouping of cells (muscle fibres) bound together by connective tissue
Tendons link bones to skeletal muscle
Skeletal muscle fibres increase in size during growth but NO new fibres are formed
58
Ouabain
Is a poison that comes from the seeds of an African plant
It binds to the outside of the Sodium Potassium Pump and shits it down
Ouabain treatment on a cell causes for the cell to explode. More Ca+ in and Na+ out
59
Endurance Training
Increases the number of blood vessels in a muscle
Increases the number of mitochondria in the muscle fibres (ATP)
Thus increasing the ability to sustain muscle contraction over a long period
60
Disuse Atrophy
Decrease in the number of myofilaments (Lost protein) in each muscle fibre
61
Myostatin
Is a protein harmed that is activated by protease
Only active when short
It works via signal transduction pathways
IT INHIBITS differentiation to muscle cells so you can get double muscles
62
3 Major Types of Muscle Fibres
Slow-oxidative fibres
Fast-oxidative fibers
Fast-glycolytic fibers
63
Slow-oxidative fibres
Contain a type of myosin with relatively low ATPase activity but with numerous mitochondria - for prolonged, regular activity
1/4 ATP -- ADP+Pi
64
Fast-oxidative fibers
Contain a type of myosin with high ATPase activity and numerous mitochondria - for rapid actions
65
Fast-glycolytic fibers
Use glycolysis
notions a myosin with high ATPase activity but there are few mitochondria, and relatively little available myoglobin (resulting in pale colour = white muscles) for rapid, intense action BUT the sculls fatigues quickly
66
Nervous System: Consists of
Brain, Spinal cord, Sense organs, and Nerves
67
Neurons
Cells in the NS that send and receive electrical and chemical signals to and from other neutrons throughout the body
68
Nerve
Has hundreds of euros with associated glial cells
69
Glia Cells
Are cells that produce the connective tissue and organize the zones around the neutrons, producing myelin for certain nerves
70
Nerve Tract
Is a bundle of axons
71
Ganglion
Is a collection of neurone cell bodies
72
Myelin Sheath
Is formed by glial cells and acts as an insulating material
73
Sensory Neurons
Gets info from the outside world
74
Motor Neuron
Sends signals away from sensory neurons for a response
75
Interneuron
Make interconnections with other neurons
1000 to 10 000 interactions
76
Action Potential
Is generated when the neuron is stimulated over a threshold
77
How fast does a signal go?
It depends on axon diameter AND myelination
78
Axon Diameter
Broader axons provide less resistance and action potential moves faster
Example: Squids have broader axons so they can escape predators quickly
79
Myelination
Myelinated neurones are faster then unmyelinated
Note: Myelin sheath is not continuous, there are gaps at nodes of Rannvier where action potential forms the current "jumping" through to the next node
80
Synapses
Junction where neutron meets another neutron or muscle cell
There is a presynaptic cell (sends signal), synaptic cleft and postsynpatic cell (receives signal)
2 Types: Electrical AND Chemical
81
Electrical Synapses
A charge flows through gap junctions from cell to cell
82
Chemical Synapses
A neurotransmitter acts as signal from presynaptic to postsynaptic cell
83
Chemical neural transmission across synapses
When an action potential reaches the end of the neutron (synaptic terminal) the neutron responds by releasing chemical messages (neurotransmitters)
Neurotransmitters diffuse across the gap (synaptic cleft) between the neutron and a target cell (postsynaptic cell)
Neurotransmitters binder receptors in the postsynaptic cell membrane, and open ion channels
84
Acetylcholine
Neurotransmitter
Released at neuromuscular junctions
Excitatory in brain and skeletal muscles but inhibitory in cardiac muscles
85
Biogenic amines
Neurotransmitter
Derived from amino acids
Abnormally high or low levels associated with a variety of disorders (schizophrenia, depression, etc.)
Examples: Dopamine and Histamine
86
Amino Acids (Neurotransmitter)
Glutamate is the most widespread excitatory neurotransmitter
GABA most common inhibitory neurotransmitter in the brain
87
Neuropeptides
Called NEUROMODULATORS can alter response of postsynaptic neutron to other neurotransmitters
Short amino acids 2 to 15 in a row
Examples: Opiate, peptides, and oxytocin
88
Gaseous Neurotransmitters
Produced locally as needed and are short acting, influencing cells after diffusion across the membrane
Several drugs for male sexual dysfunction enhance or mimic the action of NO by relaxing the smooth muscles and allowing increased blood flow
CO (VERY low levels) may play a role in brain function
CO2 may play a role in mammalian brain function BUT better studied in fish
Really short actin
89
Insecticides
Organophosphates (OPs) inhibit insect acetylcholinesterase (ACE); DDT acts on voltage gated sodium channel
ACE - Targets enzymes so they can hydrolyze and so ACE stays on receptors and muscles canNOT relax
DDT - Keeps the voltage gated sodium channel open so the insect becomes paralyzed from the spray
Mutants in Insects cause a increase in the gene copy number (esterase) SO OPs don't work because insects becomes resistant to insecticides
90
Myasthenia graves
Reduces the number of functional acetylcholine
Autoimmune
Body mistakes OWN antigens as forge in SO reduces the number of functioning receptors
Symptoms: Blockage of antibodies binding causes difficulty in chewing, respiratory problems, and weak muscles
91
Multiple sclerosis
The myelin is destroyed
Myelin is recognized wrong so it is attacked causes demyelinating the axons
Symptoms: People have trouble walking and speaking
92
Other potions
(Local anaesthetics similar function)
Bungarotxoin - Inhibits the acetylcholine receptor IN SNAKES - After bitten = Paralyzed
Tetrodotoxin - Binds to voltage-sensitive Na+ channel IN PUFFER FISH toxic
93
Hot Pepper Receptor (Heat receptor)
SO much rushes in it takes a long time to be pumped out again so you can't feel heat for sometime
Use milk so heat goes into the fat
- Capsaicin = Hydrophobic
94
Opioid "Crisis"
Fall into coma because NO more Ca+
Binging of opioid = Inhibition of Ca+
If Narcan is administered before it is too late THEN opioids will move off the receptors and Ca+ will come in
95
Star Fish (Echinoderms)
A nerve ring around mouth connected to larger radial nerves extending to arms
96
Nerve Net
Is a simple NS found in cnidarians (Jellyfish, hydras, anemones)
The neurons connect each other in a network
97
Planaria (Flat worm)
Nerve cords extend length of animal connected by transverse nerves and a collection of neurons in head form a ganglia that performs and integration fucntion
98
Annelids (Ringed worm)
These have more neurons and ventral nerve cords that have ganglia in each segment
99
Simple mollusks (Squid, slug, snail)
Similar to annelids with a pair of anterior ganglia and paired nerve cords
100
Cephalization (Evolutionary Trend)
Increasingly complex brain in the head
Flies have a centralized brain with several subdivisions with separate functions
Advanced mollusks have brains with well developed subdivisions
101
Spirometry
Most common and important pulmonary function test
Can be used to help diagnosis and monitor Chronic Obstructive Pulmonary Disease (COPD), asthma, cystic fibrosis, etc
102
Lungs
Oxygen diffuses across the membrane of the alveoli and is picked up by the hemoglobin
Any CO2 on the hemoglobin is released because the partial pressure of carbon dioxide is low in the lungs
103
Blanketing
Silence Expression
Blanketing the genes with chromatin proteins prevents transcription = Epigenetics
104
Sickle Cell Anemia
Blood Disease
Caused by a mutation
The mutant beta-hemoglobin aggregates at a low PO2 which damages the erythrocyte membrane
- Hb causes the membrane to be sickle where it tangles in the capillaries
Causes:
- Kidney Damage
- Joint Damage
- Etc.
CAN result in Anemia
Symptoms: Fatigue, paleness, weakness, dizziness
105
Thalassemias
Blood Disease for those who live by the sea
eduction in the synthesis of Alph and beta globes
CAN result in Anemia
Symptoms: Fatigue, paleness, weakness, dizziness
106
Anemia
Too few abc and reduce the delivery of oxygen to tissues
Can result from many causes:
- Hemolytic anemia (fragile cells such as sickle cell anemia or reduced cell number as in thalassemias)
- Pernicious anemia (folic acid deficiency)
- Iron deficiency
- Malaria and other parasites that destroy abc
- Aplastic anemia (bone marrow destruction)
- Blood loss
107
Humoral Response
Fluid
Mediated by lymphocytes that mature in the bond mirror called B cells
- They mature to form plasma cells (mature B cells) that synthesize and secrete antibodies
Cells mature in bone marrow
108
Antigen
(antibody generating)
Normally a foreign protein, glycoprotein, polysaccharide
109
Antibody
Proteins that bind to antigen
Anchored to membrane
- Immunoglobulin protein family
- Each composed of 4 polypeptides
(two short (light) polypeptide chains) AND (two long (heavy) polypeptide chains)
Connect the adaptive immunity with the innate response. Thus they link invading microbes and viruses to phagocytes, complement proteins, or natural kill (NK) cells
110
B cells
All are different
When an antigen first appears only a few B cells can bind
When an antigen binds to a receptor it allows for division
Population of B cells with same specificity - Clonal selection
TWO types: Plasma and Memory
111
Plasma B ells
Secrete antibodies
112
Memory B cells
Stay in the body for a long time
113
Agglutination
Antibodies and antigens can clump together
114
After agglutination:
1. Phagocytes (dendritic cells) can easily engulf the clump
2. Natural killer (NK) lymphocytes) destroy the cells marked with antibodies
3. Activation of complement (A cascade reaction involving ~20 proteins that builds a hole in the invaders membrane)
115
Gene assembly increases diversity
Coding regions for antigen binding sites are assembled to generate genes that can be transcribed
The enzymes for the assembly are expressed only in developing lymphocytes
116
Novel Joints
Joining of cut domains is not always precise, resulting in different amino acid sequences
Overlap = Missing
Or extra
117
Hypermutation
Result of a point mutation during DNA replication, which in turn changes the amino acid sequence
118
T cells
Have a T receptor
This is a dimer with an a-and b- chain (variable and constant regions)
- Constant regions have a transmembrane domain
Amino acid sequence in the variable regions differ in different clones of T cells
Each variable region is encoded by various variable, diversity and join "gene pieces" and is assembled to the constant region
119
T cell receptor
They cannot bind to an antigen unless they also bind to MHC (major histocompatilibilty complex)
120
Major Histocompatibility Complex (MHC)
Cellular "identity tags" that are genetic markers of self
MHC l found on most cells in the body (an exception is the erythrocytes and most platelets)
- Binding is stabilized by CD8 (on kill T cells - cytotoxic T cells)
MHC ll found on antigen-presenting cells such as macrophages (or presentation cells), B cells and a few other immune system cells
- Binding is stabilized by CD4 (on helper T cells)
121
4 functions of the helper T cells
1. The helper T cell binds to an macrophage (APC - antigen presenting cell)
- Binding releases a chemical signal which stimulates mitotic division of the helper T cell (sometimes called T4 cell)
2. The helper T cell binds to B cells bearing a B cell receptor and bound antigen
- When bound IL is released which stimulates the B cells (virgin B or memory B) to divide and produce a clonal population of B cells resulting in more plasma B cells
- Humorial response to secrete antibodies
- Peptide hormones induce to grow and divide
3. Helper T cells produces cytokines which stipulate killer T cells (=cytotoxic T cells) to attack "infected" cells
- Killer T cells attack cells with specific antigen and MHC l with the interaction stabilized by CD8
- They kill by releasing perforin (makes channels or perforations in membranes of cells)
4. The helper T cell stimulates the killer T cells (cytotoxic T cells) by the production of cytokines (Its) to produce a clonal population of killer T cells and memory killer T cells
- Stimulation also produces populations of killer T cells
- Population of killer T cells (including memory killer T cells) with the same specificity after proliferation
122
Immune Tolerance
Body distinguishes between self and non self components
Huge diversity of lymphocyte receptors also generates receptors binding to self
Mechanisms prevent an immune response to "self antigens"
- Clonal deletion of lymphocytes during early development: self recognizing T cells in the thymus are destroyed by apoptosis (= cell death)
- Clonal inactivation outside of they thymus: potential self reactions T cells become non-responsive
- B cells undergo similar processes
123
Autoimmune disease
The immune system attacks the body's own tissue and cells
- Multiple sclerosis = myelin attacked
- Myasthenia graves = acetylcholine receptors on skeletal muscle cells attacked
- Rheumatoid arthritis = joints attacked
- Type 1 diabetes mellitus = insulin producing cells destroyed
- Hashimoto's dienares = thyroid attained (bacterial infection)
Treatment: Drugs like cyclosporin or hormones like glucocorticoids that inhibit the production of cytokines
124
No functional B cells
No agglutination response
125
Absence of functional T cells
Happens if the thymus doesn't develop normally
Example: DiGeorge Syndrome - Small selection of chromosome 22
Treatment: Includes transplants of bone marrow and or thymus
126
Cancer Cells
Are:
Immortalized = To continue to divide indefinitely
Transformed = Grow without formal growth constraints
May undergo metastasis = Has cell leaving so it goes from benign to malignant
127
Causes of Cancer
1. Inherited mutation (from family)
2. Environmental causes (smoking, radiation, dyes, and asbestos)
3. Genome alterations (example: rearrangements of DNA, increases in gene copy number, jumping gene or alterations in chromosome associated proteins such as histones)
- Blanket = Prevent
- Jumping gene = Genome alterations
- Oncogenic (= cancer causing) viruses (DNA or RNA virus)
128
Retrovirus
RNA virus that can integrate into the host DNA
129
How do retroviruses cause cancer?
1. Integration of the provirus near a gene important for cell growth and division (slow going cancer = Example: Leukemias)
- When these viruses integrate into host DNA it can result in DNA repeats at the site of the insertion
- Cell is transformed and targets RNA polymerase
2. Retroviruses can carry a gene for cell growth and division as a passenger in their genome
- Transforming virus and can go to next cell
- CAN lead to fast growing cancer - We have extra copy
130
HIV
Preferentially enters helper T cells, using (HIV looks for) CD4 proteins as receptors
Once gp120 binds CD4 , a conformational change allows gp120 to interact with chemokine co-receptors or co-stimulant proteins (CCR5)
Thus stabilized, gp 41 interacts with the host cell and the two membranes (viral and host cell) fuse.
HIV also enters other cells such as the antigen presenting cells, cells lining the digestive tract, and microglial cells
131
After HIV
The patient makes antibodies to HIV gp120s and is nov considered HIV+
HIV provirus can hide in target cells including memory T cells
Helper T cells are destroyed by
- HIV virulent (lytic stage)
- Natural killer cells
- Killer T cells
- Syncytium formation
Helper T population can decline to ~5% of normal values
132
Tested Therapies for HIV
- Use gp120 as a vaccine
- Reverse transcriptase inhibitors (Examples: AZT, DDI, and others)
When reverse transcriptase allows AZT to be incorporated, DNA synthesis cannot continue
- Protease inhibitors (Prevents the proper processing of the viral proteins)
- Interleukin injections
- CD4 therapy (Proteins that act as receptors - Doesn't work neutralizes HIV because gp120s are covered with CD4 because HIV has a higher affinity for CD4 when its on helper T cells)
- Other (Integrate) (CCR5 change in concentration CCR5 inhibitor may discourage HIV $100/day and side effects: rash and liver)
- Cocktail $20K
- Lifetime $300K
133
HIV: Evasion of the Immune System
- Reverse transcriptase (RT = no editing capability) = A HIGH mutation mutation rate (Cannot detect mistake)
- More mutations may be generated by Rt sting between the 2 template RNAs (Generate more mutations)
- Challenges for antibody production with the icing carbohydrates on the gp120s
- Free gp120s can circulate (Helper T has gp120 antibodies and therefore more unaffected T cells get killed by killer T cells)
- The provirus hides out in cells during the latent stage
- An HIV protein (Nef) directs MHC l to the lysosomes so they don't get to the Golgi and the membrane
- Many of HIVs proteins are covered by the host cell membrane (Cannot see rest of it so HIV is clocked in the host membrane)
134
Body respond to HIV
- HUGE output of visions ~1000000000 per day
- Billions of viruses and infected cells re destroyed per day with production of ~100000000 helper T cells per day
- The proviral integration into the chromosomes can cause cancers
- HIV protein crosses the blood-brain barrier (microglial cells) and a its as a toxin to giveAIDS-associated dementia
- The immune system is exhausted and when another infection comes along there is nothing left to fight = Death :(
135
HIV Mutation Rate
HIGH mutation rate
Example: Trypanosomes (spread by tsetse flies and causes a type of sleeping sickness
Gonorrhea (bacteria that causes a venereal disease have different pills genes) 60 million cases in the world per year
136
HIV Interfere with MHC l presentation
Foot and mouth disease (An RNA virus that infects cattle, pigs and other cloven-hoofed animals)
The number of HMC l molecules getting to the surface is reduced to 50% because of disruption of the secretory pathway by viral proteins
137
HIV hide out in host cells
Example: Parasite Plasmodium which causes malaria multiples within red blood cells
138
Amines
Water soluble
Derived from tyrosine or tryptophan
Example: Dopamine (Neurotranmitter in brain that reduces mobility of gastrotinestinal tract)
139
Peptide Hormones
Water soluble
Example: Prolactin but can also include larger proteins
Cytokines as peptide hormones since it was easy to group here
140
Steroids
Lipid soluble
Cholesterol derivates, less soluble in water
141
Other
Water and Lipid soluble
Example: Juvenile hormone
Example: Prostaglandins - derived from lipids but too bulky to cross membrane = cell receptors
(NOTE: One prostaglandin causes platelets to aggregate
142
Hormone Receptors
Only cells with the appropriate receptors can respond to a particular hormone
Receptors bind non-covalently and reversibly with hormone
Subtypes or isoforms of receptors (result from alternative splicing as well as different gene products and different combinations of polypeptides) allow the same hormone to perform more than one action
Hormone concentration can also dictate the effect on a particular hormone
143
Hormones and cheating in athletic performance
Example: Testosterone - Considered an androgenic steroid because it enhances male secondary reproductive characteristics AND an anabolic steroid because it stimulates muscle cell uncle to produce more mRNAs for muscle cell proteins (myosin, actin, etc)
Example: Blood doping - erythrocyte transfusions
- erythropoietin (a glycoprotein)
144
Hormones and behaviour - Fish physiology
- Sensory receptors in salmon can detect different salinities in water as they initially migrate to the sea and back to fresh water for spawning
- Peptide hormones produced by the NS (brain) and heart (natriuretic peptides) as well as cortisol (steroid a "stress hormone") mediated these changes
- These "seawater-adapting hormone" (or natruretic peptides because they result in the excretion of large amounts of sodium in the urine) are important for getting rid of excess salt at the gills and regulating drinking-coupled salt uptake
- Natriuretic hormones stimulate the sodium potassium pump to pump out excess Na+ and the cystic fibrosis transmembrane transductase regulator to pump out excess C-
- Receptors for natriuretic peptides are found in the gills, kidney, and intestine
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Hormones and Circulatory system: Humans
In humans, natriuretic hormones are involved in osmoregulation as well as cardiovascular function
Increased amounts of natriuretic hormone are made in response to stretching the cardiac cells = results in the kidneys decreasing the absorption of Na+ therefore osmotic potential of the urine increases = Water then rushes into the collecting ducts and the volume of the plasma decreases resulting in an overall decrease in blood pressure
