Quiz 4 Flashcards
____ molecules can pass through capillary walls while _____ cannot.
1) Nonpolar (O2, CO2, lipid soluble things)
2) Plasma proteins
What is bulk flow?
Movement of water soluble substances (ions, glucose, a.as) through pores/intercellular clefts.
True or false… The lymph system carries stuff from the interstitial fluid to the venous system in either direction.
FALSE. The lymph system only moves things in one direction, towards the venous system.
True or false… The fluid that is not picked up by the venous system in a capillary bed is called lymph.
FALSE. It is interstitial fluid. It is called lymph once it is in the lymphatic system
What is the direction of the colloid osmotic pressure? What causes this force?
Plasma proteins (namely albumin) PULLS fluid from the interstitial fluid into the circulatory system. Note that osmotic pressure from the interstitial proteins also exists, however it is a nearly negligible force.
Blood velocity is ____ in arteries and ____ in capillaries.
1) Fast
2) Slow
Which direction does hydrostatic pressure go?
PUSHES out.
Where do we see the largest hydrostatic pressure drop?
In the arterioles
What is the role of a precapillary sphincter?
It’s a cuff of smooth muscle that surrounds each true capillary (right off of the metarteriole). It helps regulate blood flow. If these sphincter a close, the blood may bypass the capillary bed (vascular shunt)
True or false… The translocation of macromolecules across the capillary membranes requires ATP.
TRUE
Which are thicker, blood capillaries or lymphatic capillaries?
Lymphatic capillaries. These also have a lower pressure
Name 4 potential causes for edema
1) increased capillary blood pressure (increased plasma volume, increased venous pressure)
2) Decreased plasma colloid osmotic pressure (less albumin)
3) increased capillary permeability
4) obstruction in lymphatic system
Which layer of the GI tract contains large vessels and nerve plexuses
Submucosa
Do retroperitoneal organs have serosa or adventitia?
BOTH. They have adventitia where attached to another organ and serosa everywhere else
Smooth muscle in the GI tract has a ____ inner layer and a ____ outer layer
1) circular
2) longitudinal
What layer(s) does the pharynx lack?
Muscularis mucosa of mucosa layer and SUBMUCOSA
When the bolus passes the pharynx into the esophogus, does the trachealis muscle relax or contract?
Relax
What is the difference between serosa and adventitia?
both are connective tissue linings… However the serosa is also covered in MESOTHELIUM
The upper 1/3 of the esophogus is _____ muscle while the lower 1/3 of the esophogus is ____ muscle
1) skeletal
2) smooth
Describe the lower esophageal sphincter.
It is not anatomically distinct. It is made up of a thickening of the muscularis external. When it relaxes, it allows the passage of the bolus
What type of tissue is found in the esophagus and stomach?
Stratified squamous in esophagus. Simple columnar in stomach.
Explain the differences in the pits/glands in the different regions of the stomach.
Cardia: short pits, long glands
Body/fundus: relatively long glands
Pylorus: long pits, short glands.
Chief cells secrete…
Pepsin and lipase
Parietal cells secrete (2 things)…
HCl and intrinsic factor
Where are the stem cells located in the GI tract?
At the top of glands (at the bottom of pits)
G cells secrete ____ which functions to…
Gastrin. This functions to stimulate the parital cells to secrete acid.
Describe the differences between surface mucus cells and mucous neck cells.
Obviously the surface mucus cells are on the surface… But also…
Surface mucous cells are more columnar, secrete bicarbonate to diffuse the acid.
Mucous neck cells are rounder, less numerous, and have apical granules
What does gastric intrinsic factor do?
Aids in the absorption of vitamin B12
G cells secrete ____, ____, and _____ from the _____ part of the cell into the _____. _____
1) Gastrin/histamine
2) Ghrelin (satiation)
3) serotonin
4) basal
5) blood
6) 🤓
Explain the cephalic phase
It’s responsible for 30% of HCl secretion. Stimulated by smell, taste, conditioning.
Strictly due to vagus nerve
Describe the gastric phase
60% of HCl secretion.
Stimuli are DISTENSION, amino acids, and small peptides.
Due to vagus nerve and Gastrin and local reflexes.
True or false… Fats are absorbed into the lymphatic system instead of blood.
True
What do Microfold (M) cells do?
They are located over peyer’s patches (so they are in the ileum). They endocytose antigens and dump them into the peyer’s patches (where lymphocytes and dendritic cells reside)
What are Enterocytes?
What are Paneth Cells?
What are Enteroendocrine Cells?
1) columnar cells that absorb water
2) secrete anti microbial molecules (lysozyme, defining, phospholipase A) (also are progenitor cells) located at the bottom of crypts
3) Local and systemic signals relating to digestion
In the stomach, the chemical digestion of what begins?
Lipids (by lipases)
Proteins (by pepsin)
Although carbohydrate digestion occurs, carb digestion begins in mouth
Explain the absorption of lipids
1) Bile EMULSIFIES lipids into micelles.
2) gastric lipase digests the lipids into FAs and glycerol
3) diffuse into cells
4) resynthesized in the SER
5) pass through the RER to the Golgi where they are packaged into CHYLOMICRONS
6) enter the lymphatic circulation, thus bypassing the liver
How are amino acids and carbohydrates absorbed?
Through active co-transport with sodium. (Fructose freely diffuses.. For whatever reason)
What things do the Enteroendocrine cells secrete and what do they do? (4 things)
Secretin: stimulates bicarbonate and water secretion of pancreas and bile ducts, inhibits secretion of H+ by parietal cells of stomach. (This neurualizes pH in duodenum
Cholecystokinin: signals immediate satiety to brain. Also causes contraction of gall bladder.
Gastri inhibitory peptide: stimulates insulin secretion by B cells in pancreas
Peptide YY: signals long term satiety.
What is the myenteric plexus?
Collection of symp. And parasympathetic nerves that regulate GI function and sense distension
Describe the mucosa of the large intestine
No Villi
Tubular columnar intestinal glands (so no pits?)
Goblet and absorptive cells
Name the five types of common biochemical reactions. Which is the way electrons are transferred in a biological system?
1) making/breaking carbon bonds
2) molecular re-arrangements
3) free radical reactions
4) group transfers
5) REDOX reactions
Redox is most common in bio systems
Name 5 common group transfers and the enzymes that accomplish them.
Phosphorylation - Kinase Ubiquitination- ubiquitin ligase Acetylation - acetyltransferase Methylation - methyltransferase Hydroxylation- hydroxylase
ATP can provide free energy via two different methods. What are these methods?
Group transfer and hydrolysis of itself (magnesium stabilizes this and allows it to occur)
As the concentration of ATP increases, the amount of energy released per ATP increases. True or false?
True
Oxidation involves the ____ of electrons from a molecule. Does this release energy or require it?
1) removal
2) this releases energy
Name four ways to transfer electrons.
1) direct electron transfer
2) hydride ions
3) hydrogen atom transfer
4) combination with oxygen
Reduced carbon chains are energy poor. True or false?
False, they are energy rich.
Do double bonds in a fatty acid decrease or increase the amount of potential energy? Why?
It lowers the amount of energy because there is less hydrogen to store electrons… Basically
The cervix contains glands that secrete mucus… What is the function of this?
The mucus serves to block sperm entry except for the mid cycle
Where are the ovarian vessels located?
Within the suspensory ligament
The ovarian ligament is a remnant of the ___
Gubernaculum
True or false… The Infundibulum is responsible for creating currents to move the oocyte into the uterine tube.
False. The fimbrae is responsible for this
The broad ligament is similar to mesentary in that it forms a double layer. What layer of peritoneum forms the broad ligament?
Parietal peritoneum
Name the arterial supply of the following… Ovary, uterus, vagina
Ovary: ovarian arteries (from aorta)
Uterus: uterine arteries (from internal iliac artery)
Vagina: vaginal arteries (from internal iliac artery).
Note that the ovarian arteries and uterine arteries can anastomose
Name the muscles of the perineum (6)
Ischiocavernousus
Bulbospongiosus
Superficial trans perineal
External anal sphincter
Deep trans perineal
Levator and
The greater vestibular glands are homologous to the _____ gland in males
Bulbourethral
The inferior portion of the vagina is innervated by the ___ nerve while the superior portion is ____
1) pudendal nerve (somatic)
2) visceral
The pudendal nerve arises from ventral rami of…
S2-S4
Pelvic splanchnic nerves (parasympathetic) arise from where?
S2-S4
Explain clitoris INNERVATION
Somatic sensation - pudendal nerve
Parasympathetics are responsible for erection of clitoris
Pudendal nerve is responsible for orgasm (motor)
Since parasympathetics preganglionic neurons meet their postganglionic neuron in intramural ganglia.. Where do the parasympathetics of S2-S4 meet?
Uterovaginal plexus
An indirect hernia in a male occurs where? What about direct hernia?
The deep inguinal ring, (possible to inguinal canal, to superficial inguinal ring… Umm yikes!)
Direct hernia… Enters through a weak point in the fascia of the abdominal wall (hesselbach triangle)
Describe the difference between the right and left gonadal veins
Right goes to IVC. Left goes to left renal vein
What are some of the functions of the prostate gland?
Secretions contribute to sperm motility.
Smooth muscle contractions expel semen into urethra.
Neutralizes pH of vagina
What are some functions of the bulbouretrhal gland?
Secretes fluid to neutralize pH of urethra for spam
The urethra is located within what structure in the penis?
The corpus spongiosum
Competitive Inhibiton.
Inhibitor competes with substrate.
Km shifts to right
Vmax unchanged
Uncompetitive inhibition
Inhibitor binds to ES complex but not enzyme alone.
Km shifts left (due to less functional enzyme)
Vmax shifts down
Noncompetitive inhibition
Inhibitor binds to enzyme or ES complex
Km no change
Vmax shifts down
Mixed inhibiton
Inhibitor binds enzyme or ES complex. Affects substrate binding
Km shifts right
Vmax shifts down
Name 6 different types of receptor families and what they do
G-protein coupled receptor - G protein splits off to activate other stuff
Receptor tyrosine - receptor becomes enzymatically active
Receptor guanylyl cyclase- enzymatically active and turns GTP to cGMP.
Gated ion channel - ions go in
Adhesion receptor - binds to extra cellular structures and regulates cell organization
Nuclear receptor - hormone binding allows direct transcription regulation
What is the Kd?
Concentration of ligand in which 50% of the receptors are binding ligand
How does the plasma membrane play an active role in signaling?
Receptor localization
Ligand exposure
Signaling complex formation
Enocytosis
What are the two different types of lipid rafts?
Caveolar and planar
What are the “traffic control” proteins in the endocytic pathway?
The Rab GTPase proteins
In what ways do chemical reactions transfer information in a signaling pathway?
Complex formation or dissociation
Structural changes (ATP to cAMP)
Post-translational modifications (phosphorylation)
Explain the Mitogen activated protein kinase pathway
Activated RAS will activate MAPKKK which activates MAPKK which activates MAPK which activates stuff
Explain the Janus Kinase signaling pathway
Upon ligand activation of the receptor. The protein dimerizes and recruits JAK. JAK phosphorylates receptor. Receptor recruits STAT. JAK phosphorylates STAT. Two phosphorylated STATs dimerize. The dimer regulates transcription.
Explain the PI3K pathway.
Receptor dimerizes. Receptor phosphorylates the membrane bound lipid PIP2 (which becomes PIP3). PIP3 activates PDK1 and AKT. This functions to reduce the level of cell survival.
Explain the phospholipase C pathway.
G protein coupled receptor. G protein activates PLC. PLC cleaves PIP2 into IP3 and DAG. IP3 opens calcium channels in ER. Calcium aids in the activation of PKC.
DAG binds to PKC and membrane. PKC activated, then phosphorylates substrates.
Epinephrine signaling. What does it do and what signaling pathways are involved?
Affects vascular tone
G-protein and PLC pathway
Insulin signaling. What does it do and what signaling pathways are involved?
Regulates cell division and metabolic processes
Transports glucose into cells, alters blood sugar
MAPK, PI3K, and RTK
The Alpha adrenergic receptor in the epinephrine G protein coupled receptor signaling pathway activates what pathway? What about the Beta adrenergic receptor?
PLC pathway
Beta affects the cAMP levels
What does the Qt interval represent?
Ventricular action potential (total)
What does the PR interval represent?
Atrioventricular conduction. (Signal going from atria to ventricles.
What does the QRS wave represent?
Duration of ventricular depolarization.
What does the ST segment represent?
The duration of the ventricular plateau
What is the quiescent phase?
Isovolumetric relaxation of the ventricles.
What is phase 0, 1, and 2?
Rapid depolarization. Phase 1 is rapid repolarization followed by phase 2 which is the plateau.
What causes the rapid depolarization in the working cells and pacemaker cells?
Na for working cells
Ca for pacemaker cells
How is the plateau phase sustained?
Sustained increase in Ca permeability while decrease in K permeability
Baroreceptor reflex vs bainbridge reflex.
Baroreceptor - increases/decreases heart rate due to changes in arterial pressure.
Bainbridge - increases rate in response to increase of volume in atria. (Protective)
Each large box on an ECG represents….
.5mV and 0.2 seconds
How do you calculate HR?
R-R interval. (Each large box is .2 seconds, so each small box is .04seconds)
60/R-R interval.
What do brunners glands do?
Secrete mucus
What is long QT syndrome and why is it bad?
The qt interval is longer than normal. This can lead to ventricular tachyarrythmias
What is hyaluronate?
It is a glycosaminoglycan, found on proteoglycans. It is found in corneal structures of the eye and gives viscoelastic properties.
What is the type of bond in sucrose? What is unique about sucrose?
Glucose 1 alpha
Sucrose 2 beta
Sucrose is a non reducing sugar (as well as trehalose)
True or false…. Monosaccharides are reducing sugars
True
Fructose is a ketose, thus it will give rise to ____. Glucose is an aldose and will give rise to ____.
1) acetal
2) hemiacetal
What is a reducing sugar?
It has a hydroxyl group on its anomeric carbon available. They will reduce other things to become oxidized. They will react with copper for form a reddish precipitate.
How many carbons are in Xylose? What about Threose?
Xylose = 5 Threose = 4
What type of tissue is found in the submucosa?
Dense irregular
What layer is the lamina propria found?
In the mucosa
What is mesothelium? What type of tissue?
It is a lining of simple squamous internal lining epithelium that can overlay the adventitia
True or false… The epithelium in the pharynx is non-keratinized stratified squamous. Has a lamina propria containing longitudinal elastic fibers
True
Where do the greater, lesser, and least splanchnic nerves of sympathetics synapse?
Pre aortic ganglia
The sympathetics of T5-T12 innervate what?
Foregut and midgut
Where do the lumbar splanchnic nerves arise from, where do they synapse, what do they innervate?
From L1 and L2. Synapse in the preaortic ganglia, innervate the hind gut.
What does the vagus nerve innervate, where does it synapse?
It innervates the foregut and midgut. Synapses close to target
What is the sacral portion of parasympathetics, what does it innervate, where does it synapse?
S2-S4
innervates the hindgut
Synapses close to the target
True or false… Parasympathetics follow the same path as sympathetics
True
