Intro To Alimentary System Flashcards
(170 cards)
1
Q
Which are the solid organs of the digestive system? (4)
A
The accessory organs.
Salivary glands
Liver
Pancreas
Gallbladder
Why ate the salivary glands so important? Could we live without them?
2
Q
Recall the symptoms of Sjogrens disease
A
See canva patient ‘Kathy’
Fatigue- extreme like altitude sickness
Aches
Eye dryness
Vaginal dryness
Mouth dryness
May have eye ulcers, dental cavities, candida infections of mouth and vagina
3
Q
Why would you have dental cavities in Sjogren’s disease?
A
Saliva is there with antibacterial properties, and lubrication on the teeth that protect them when grinding and chewing (imagine those sumo wrestlers on the teeth).
4
Q
What med is used in sjogrens to stimulate tear and saliva production?
A
Pilocarpine (oral)
5
Q
Hydroxycholoroquine is what and used for what
A
It’s a DMARD used for: sjogrens, lupus, RA, and also malaria weirdly enough
6
Q
What antibodies for sjogrens and what image to remember
A
It’s that florist shop: Abrola.
Anti ss-a and anti ss-b, aka anti-ro and anti-la
7
Q
What quick test with filter paper can you do for sjogrens, and what test do you use for diagnosis?
A
Schirmir test
And
Blood test aka serology test
8
Q
What’s a serology test
A
Antibody test
9
Q
Why do we need the 99% of water component saliva, apart from softening and moistening?
A
Dilute particles to reduce the osmotic pressure, which was raised because the food has been broken down.
Osmotic pressure is essentially the pressure needed to stop water from moving through a semipermeable membrane when it’s trying to balance out the concentration of dissolved stuff on both sides. It’s like the pressure you’d feel if you were trying to keep a bunch of people from pushing through a door to get to the other side
So MORE dilution, more water in the saliva = isotonic/ same concentration everywhere, everything’s equal.
10
Q
What catalyses the breakdown of polysaccharides like starch and glycogen into what?
A
A-amylase, into disaccharides
11
Q
Structure of the oesophagus
A
12
Q
Function of the oesophagus
A
13
Q
Structure of the atomach
A
14
Q
Function of the stomach
A
15
Q
How many muscles does it take to swallow?
A
26
16
Q
How many nerves does swallowing involve?
A
6
17
Q
Which two nervous system mechanisms control chewing? (2)
A
Voluntary- somatic nerves for skeletal muscles of mouth and jaw
Chewing Reflex via mechanoreceptors
18
Q
We can eat for hours. This is made easier by the chewing reflex. When pressure of food is felt by mechanoreceptors, what happens?
A
Inhibition of jaw muscles I.e. they relax
19
Q
What three salivary glands do we have
A
Sublingual
Submandibular
Parotid
20
Q
The parotid glands extend from where
A
Top of the ear and mainly irrigates top/upper part of the mouth
21
Q
Which salivary gland is most used when you’re talking
A
The sublingual, irrigates just under the tongue
22
Q
The polysaccharide starch can be broken into the disaccharides. For starch, which are these?
A
Maltose and glucose
23
Q
Where are the two places that a-amylase is secreted?
A
Salivary glands and also the pancreas
24
Q
Autocrine vs endocrine vs exocrine vs paracrine
A
Auto- works on same cell
Para- works on neighbouring cells
exo- ducts
endo- directly into bloodstream
25
Layers of the alimentary canal???
Mucosa-
epithelium, lamina propria (absorb and secrete)
muscularis mucosae (for motility)
Submucosa- large blood vessels, neurons, lymph nodes
Muscularis externa
Serosa/ adventitia
this ms,ms and within mucosa, ELM like elmfield terrace
26
When Serosa/ adventitia? (This is connective tissue)
Serosa = in peritoneal cavity
Adventitia otherwise eg rectum
27
Muscularis externa is made up of what two muscle layers
Circular- inner layer (constricts lumen, makes lumen smaller) and longitudinal (shortening in length of GIT)
28
Two plexuses ie the intramural ones?
Submucosal and a myenteric
29
Mouth and esophagus rectum and anus, what cells
Stratified squamous
30
Stomach, small and large intestine what cells
Simple columnar, only one layer for easy absorption
31
That picture I took- nerves of the GI system
32
Salivation: this has two stimulators / controlling nerves (for autonomic- remember it’s not voluntary therefore not somatic!)
What are they?
Parasympathetic (vagus) and sympathetic (splanchnic nerve)
33
What three main arteries supply the GIT?
Celiac trunk, super and inferior mesenteric artery
34
The small intestine is fed by what two arteries
Celiac and superior mesenteric
35
The colon is fed by what two arteries, and where is the split?
S and I mesenteric arteries…. Descending and Cecum is the I
36
Venous drainage of GI tract ????
37
Maltose is what?
Glucose and glucose
38
Sucrose is what
Glucose and fructose
39
Lactose is what
Glucose and galactose
40
Where and what can degrade cellulose
Bacteria in the large intestine
41
What is a PPI
a proton pump inhibitor, for example omeprazole. Its used to treat gastric reflux, stomach ulcers, H pylori infections etc. They bind to the proton pump to inhibit gastric acid secretion.
42
Poly saccharides the have alpha 1,4 glycosidic bond. What enzyme is the only one that can break that?
For example, this polysaccharide could be starch
amylase, which can be found in saliva, and pancreatic juices (which are released into the duodenum)
43
Sodium potassium pump: where exactly is this located in the lining of the stomach? How is it involved in carb absorption?
the basolateral side of the epithelium
3 Na out, 2 K in
It provides a concentration gradient for sodium, so that the SGLT1 transporter on the apical side, lets in both glucose and Na
44
Glucose transport from lumen to blood relies on what three pumps/transporters? Draw this is unsure.
basolateral membrane: Na/K pump creates gradient for sodium
SGLT1 transporter lets in both Na and glucose and galactose
45
Normal glucose levels in the blood
between 4 and 7 mmol/l, whereas prediabetes is
46
Sodium plus glucose rehydration in the case of cholera. Why?
glucose encourages sodium to enter via the sglt1, and water follows sodium
47
Proteins are what
Polymers of amino acids linked together by peptide bonds
48
Fat soluble vs water soluble vitamins. Which are the fat soluble?
A D E K
49
water soluble vitamins are not stored in the body. They can be easily lost when you poo such as
and except which one?
B and C. Except B12, which can be stored in the liver
50
where are fat soluble vs water soluble vitamins absorbed
Fat soluble = in the duodenum as fat molecules, vs water soluble is in both small and large
51
why would most of the food we eat be formed from macromolecules?
In order to keep osmolarity low, so that you don't attract too much water. We need a controlled breakdown, or we'll suddenly withdraw a lot of water to keep osmolarity
e.g. glucose = glycogen, amino acids = protiens
52
maltose, sucrose and lactose are disaccharides broken down by what?
maltase, sucrase, and lactase
53
where are carbs broken down and absorbed?
in the small intestine
54
how are carbs absorbed?
transcellularly or paracellularly
55
What pumps/transport do proteins use to be absorbed, after being broken down?
3 different.
First of all, the Na/K pump to create gradient, and then the SAAT1 pump to let in amino acids and Na. I.e. the sodium/ amino acid transporter.
Then they are transported across the basolateral membrane via facilitated diffusion
56
peptide bonds in proteins are hydrolysed by what
proteases and peptidases
57
Amino acids use the sodium-amino acid transporter one to enter on the apical side. (SAAT1). What about di or tri-peptides?
They would use PEPT1
58
What transporter does penicillin use to enter on the apical side?
PEPT1
59
What three types of 'lipases' digest fats?
lingual
gastric
pancreatic
60
what 'hurdles' need to be overcome for the pancreatic lipase to be secreted?
gastric acid and presence of partially digested fats stimulate our secretary and CEO: secretin (stimulates bicarbonate production for optimum pH) and CCK (stimulates pancreases for pancreatic lipase, and also the liver to release bile
61
how does bile emulsify fats/lipids
bile salts and phospholipids on the outside, with hydrophobic internally, surrounding the the fatty acids and monoacylglycerol, polar on the outside.
62
how are the micelles absorbed in the apical side?
they turn back into fatty acids and monocylglycerides
63
what happens to the fatty acids and monocylglycerides on the basolateral side?
well they become chylomicrons, then pass through lacteals and enter the lymphatic system
64
how is iron absorbed? Then what happens? (2)
iron is absorbed by being transported across the duodenal brush border by DMT1. 1) it can be found combining with ferritin, and being stored. 2) Unbound iron binds to transferrin
65
what drugs might inhibit iron absorption
PPI's as need right pH
66
PepT1 is a transporter on apical needed for larger amino acids ie di and tri peptides to be absorbed in- as they can’t use the usual sodium/amino acid transporter. How is this activated?
By the sodium hydrogen pump which pumps out hydrogen ions to create a pH microclimate
67
in layers of the gut: we know the muscularis externa is made up of circular, then longitudinal muscle layers. What, then, is the muscularis mucosae of the mucosa?
just the muscularis interna that is there for local movement of the mucosa
68
what is motility, how does it work
the ability of an organism to move independently via metabolic energy
69
what's segmentation
churning up, moving food back and forth, of circular muscles to make lumen smaller
70
what's peristalsis
moving from mouth to arse, constriction of longitudinal muscles to shorten lumen
71
where is water absorption
large intestine
72
where is meissner's plexus located?
submucosa
73
which plexus is located between the circular and longitudinal muscles in the muscularis externa? (msMs)
Myenteric. That makes sense. It innervates the MAIN muscles. ( the muscularis interna/mucosa is located in the mucosa and is involved in local movement only in the mucosa.
74
difference between the serosa and the peritoneum- after all, they are both similar in being two layered- having a visceral layer and a parietal layer.
serosa- means visceral layer is touching organs that are within the peritoneum. includes stomach, spleen, liver, duodenum and transverse colon. binds these organs together
vs adventitia is for the retroperitoneal and binds the organs outside the p. cavity to the abdominal wall
75
parasympathetic of the GIT is from the vagus nerve. What is the exception?
salivation = facial and glossopharyngeal
76
inhibitory control of GIT is what nerve
splanchnic, is sympa
stimulatory is vagus obvs cuz its parasympa
77
veinous drainage of stomach
gastric veins
78
veinous drainage of pancreas
splenic vein
79
veinous drainage of small, caecum, ascending, and transverse =
superior mesenteric vein
80
descending, sigmoid and rectum veinous drainage =
the inferior mesenteric vein
81
When in development is body axis established?
week 2
with the gene PTX2
82
week two embryology
vs
week 3
week 2 = bilaminar disc formation
week 3 = trilaminar disc formation
83
one word to describe embryology between wee 3 and week 8?
organogenesis
84
Exposure to teratogenic drugs during which weeks can cause organ malformation?
3-8 because this is when organogenesis occurs
85
The right vagus nerve supplies posterior part of the stomach and the left vagus supplies the anterior wall of the stomach.
86
Abdominal wall muscles come from which germ layer
Mesoderm
87
Peritoneum coverings come from which germ layer
Mesodermal
88
Connective tissue comes from which germ layer
Mesoderm
89
Epithelial lining of the GI comes from which germ layer
Endoderm
90
spleen is what origin
91
where does the midgut extend to?
opening of the bile duct to the proximal 2/3 of the transverse colon
makes sense because bile duct is related to the liver, and the liver originates in the hindgut
92
what week does umbilical herniation (of midgut) occur?
week 6
93
Which parts of the colon are retroperitoneal?
ascending and descending
94
what's the transverse mesocolon?
mesentery of the transverse colon
95
mesentery of the small intestine is called what
the mesentery proper
96
Symptoms of malrotation due to abnormal development.
One of the earliest signs of malrotation is abdominal pain and cramping caused by the inability of the bowel to push food past the obstruction.
Babies with cramps and pain due to malrotation frequently follow a typical pattern: they may draw their legs up and cry, settle for about 10 to 15 minutes and then begin to cry again.
97
origin of the anal canal
the cranial part is endodermal in origin, whilst the caudal part is ectodermal in origin
98
Blood supply to the anal canal.
The anal canal above the pectinate line is supplied by inferior mesenteric artery and below the pectinate line is supplied by internal pudendal artery, which is a branch of internal iliac artery.
99
What's a uro-rectal fistula
when the rectum has connection with the urethra- this usually occurs in males.
100
what do the following germ layers, which develop during gastrulation.
ectoderm
mesoderm
endoderm
ectoderm = This forms everything that makes someone attractive and organs you can touch: skin, hair, teeth, nails. And then also mouth, anus, nostril linings. This also develops into the nervous system. Seeing someone attractive makes you nervous?
mesoderm = Mesoderm
MSK, CV, repro. I remember this as everything that makes a man attractive: their muscles and bone structure, their heart, and their reproductive organs.
endoderm = Genderless organs. The bladder, pancreas, thyroid, parathyroid, liver, lungs, GI tract.
101
What happens just before gastrulation?
Bilaminar disc, hypoblast cells then epiblast cells
Then the primitive streak
Then migration of epiblast cells to form the third layer
102
What happens in week 2 and 3 of embryonic development?
Week 2 = when the bilaminar disc development occurs.
Week 3 = when the trilaminar disc development occurs.
103
If I'm picturing the development of the gut tube with the piece of paper imagery I had described in canva, then I can picture the folds to create the 'floor' of the tent. Those floor tiles actually become two layered. What are these two layers?
We're talking about the mesodermal layers here. The mesoderm separates into visceral and parietal layers. That visceral one is the splanchnic lateral mesoderm, which becomes the muscularis externa
104
The layers of the gut tube: mucosa and muscularis externa. Where do these layers originate?
Mucosa = the endoderm
Muscularis externa = think. It's muscles. Must be the mesoderm.
And remember that the mesoderm develops into two layers? Well, we have the visceral/splanchnic layer that becomes the muscularis externa. The other parietal layer becomes like
105
The endoderm extends out to become the umbilical cord and what duct
vitelline duct
106
when might an umbilical hernia disappear
by 4-5 years
107
where does the mesoderm rupture and why
pharyngeal membrane to become the mouth
cloacal membrane to become the anus and opening of the urogenital systems.
108
why does your breath smell in the morning
because you have less saliva overnight
109
the serous alveolus of salivary glands will secrete what
alpha-amylase and it will also secrete lysosomes.
110
Function of lysosome in regards to saliva?
binds to bacteria, ruptures the wall, and kills it.
111
Sympathetic is inhibitory everywhere in the GI tract except where?
the salivary gland.
112
ALL of the GI tract is stimulated by what nerve (except the salivary glands)
the vagus nerve
113
the salivary glands are stimulated by which cranial nerves
facial and glossopharyngeal
stimulation means profuse watery saliva, not viscous.
114
the activation of which receptor leads to high mucus content in saliva
alpha one adrenoreceptors by norepinephrine
115
the activation of which receptor leads to high amylase content in saliva
beta two adrenoreceptors
116
The oesophagus is stratified squamous epithelium and is non-keratinised. The skin is stratified squamous epithelium, and is keratinised. Why is there a difference?
Because the oesophagus needs not be rigid, whereas the skin needs that extra rigidity and
117
Function of glands in the oesophagus
ducts provide lubrication
118
How does the muscularis externa split in the oesophagus?
upper1/3 is skeletal muscle
lower 2/3 is smooth muscle
119
Heartburn occurs when stomach contents pass through where
the lower esophageal sphincter
120
why do we need oesophageal sphincters?
upper one guards the airway- stops air entering during breathing, and stops food from travelling up and causing aspiration
the lower one stops stomach contents from being regurgitated.
121
why might babies regurgitate
upper oesophageal sphincter may not be completely working
122
what part of swallowing is voluntary
pushing the bolus to the back of the mouth with the tongue
123
To the patient, what does regurgitation feel like vs vomiting
vomiting is *forceful* expulsion of gastric contents, probably preceded by feelings of nausea
124
After stomach cancer, with partial removal of the stomach, what life-style changes would someone need to make
they would need to have certain foods, as they wouldn't have had the stomach digestion phase.
for example, whilst carb digestion starts in the mouth with amylase, protein digestion starts mainly in the stomach.
125
where is intrinsic factor produced?
GASTRIC epithelial cells.
Whilst the absorption occurs in the distal ileum.
126
what part of the stomach connects between it and the oesophagus?
the cardiac region.
because food first goes to the 'heart' of the stomach.
127
why is the pyloric sphincter 4 layer?
Because it is inside the peritoneal cavity. so it has:
mucosa (elm)
submucosa
circular muscle
longitudinal muscle
serosa
128
where is the antrum of the stomach?
closest to the greater curvature
129
muscle layers in the stomach
circular
oblique - for twisting
longitudinal
130
Purpose of rugae of the mucosa and submucosa of the stomach?
It's kinda like different plates in the stomach to help the stomach contract to a smaller size, or enlarge
131
In terms of histology, what makes the stomach distinguishable?
surface mucus cells, with gastric pits and gastric glands and presence of mucus neck, chief and parietal cells.
132
133
The esophagus has 3 constrictions which you need to be aware of if you are passing instruments through the oesophagus into the stomach; where are these?
Cervical region like 15 cm down from incisor teeth (IT)
Thoracic 20cm down where crossed by arch of aorta and also left main bronchus just after that
Diaphragmatic where is passes through the oesophageal hiatus of the diaphragm, 40cm from IT
134
McBurney's point
135
The dermatomal level of the umbilicus is T10, what is the vertebral level?
L3-4- same as where the bottom of the kidneys are located
136
external oblique insertion and origin
ribs 5-12 above, and onto the pubic tubercle, symphysis, and asis, iliac crest, linea alba
137
ribs 7-10 either correlate to the external oblique muscles, or the costal margin. Which is it?
Ribs 7-10 contribute to the costal margin, whereas the external oblique muscles attach onto the 5th-12th ribs
138
action of external oblique
abdominal press, lateral flexion, rotation, flexion of trunk when contracted bilaterally
139
internal oblique is located deep to the external oblique. Attachments?
Originates from the inguinal ligament, iliac crest and lumbodorsal fascia. It inserts onto ribs 10-12
140
lateral border of the rectus abdominus is demarcated by what surface anatomy
the Linea semi-lunaris lines
141
why would a midline surgical incision be preferred?
Because that would be through the linea alba.
It can be extended the whole length of the abdomen by curving around the umbilicus. The linea alba is poorly vascularised, so blood loss is minimal, and major nerves are avoided. It can be used in any procedure that requires access to the abdominal cavity.
142
whats the craic with the paramedian incision
Similar to the median incision, but is performed laterally to the linea alba, providing access to more lateral structures (kidney, spleen and adrenals). This method ligates the blood and nerve supply to muscles medial to the incision, resulting in their atrophy.
143
the abdominal wall muscles are innervated by the thoracoabdominal/ intercostal nerves T7-11, and T12 the subcostal nerve. Why is T12 special
Because it is SUBcostal. It's not an intercostal nerve. It's special.
144
inferior to the actuate line, what is deep to the rectus abdominus
the transversalis fascia
145
explain rectus sheath before actuate line
eo and io superficial, deep = io and ta and transversalis fascia
146
Caput medusa is the formation of dilated abdominal wall veins which extend from the umbilicus. Why might this occur?
The superficial veins might become dilated secondary to portal hypertension in severe cases. This can lead to
147
content of inguinal canal
spermatic cord/round ligament
and ilioinguinal nerve
148
bottom wall/ floor of inguinal canal
inguinal ligament
maLt inguinal ligament (and lacunar ligament? don't even know what that is).
149
anterior wall of inguinal canal
mAlt, two aponeurosis'
external oblique and reinforced by the internal oblique near the iliac crest
- makes sense, because the internal oblique goes all the way to the iliac crest but the external oblique only goes to the pubic tubercle
150
what forms the conjoined tendon and where does it insert?
if unsure see the youtube video '3D tour of the inguinal canal'
both the transversalis abdominis and the internal oblique, and it inserts onto the pubic tubercle. It was formed just after the internal oblique and the ta travel together to form the roof of the inguinal canal
151
posterior wall of the inguinal canal
malT
2xT,
transversalis fascia and the conjoined Tendon
152
roof of inguinal canal
io and ta, that at the corner forms the conjoined tendon
Malt
think 2xm, two muscles
153
the deep inguinal ring is actually a hole in what
the transversalis fascia
154
the superficial inguinal ring is actually a hole in what
the external oblique aponeurosis
cuz thats the anterior wall
we also see the internal oblique reinforcing part of the anterior wall
155
98% of people are diagnosed with sjogrens after what symptom presents
nerve pain
156
What anatomical point is used surgically to determine the location of the superficial inguinal ring?
The superficial inguinal ring can be located surgically by identifying the pubic tubercle. The superficial inguinal ring lies just superior and lateral to the pubic tubercle
157
where is the deep inguinal ring located
halfway along the inguinal ligament, i.e. halfway between the ASIS and the pubic tubercle
158
As the inguinal canal is forms an outpouching of the abdominal wall, the layers are pulled with it to form the wall of:
the spermatic cord and the scrotum
159
list all the back muscles and their attachments. see teach me anatomy for answers because bro you should know this
an example answer:
quadratus lumborum. Comes from POSTERIOR iliac crest, lumbar vertebrae one to five, and 12th rib. Lateral flexion of torso, and bilaterally = extension of torso
160
which abdominal posterior back muscle attaches to the femur
iliopsoas
161
What does the central tendon of the diaphragm attach onto?
the pericardium
162
What levels do the three major abdominal vessels come off?
T12 > celiac
L1 > superior mesenteric
L3 > inferior mesenteric
163
Where does the inferior mesenteric vein drain into?
The splenic vein
164
The foregut is supplied by the celiac trunk which comes off the aorta anteriorly at T12. Therefore, all lymph for foregut structures will drain to which lymph nodes?
Pre-aortic nodes at T12
165
Name the prevertebral sympathetic ganglion
celiac ganglion
superior mesenteric ganglion
inferior mesenteric ganglion
so abdominopelvic splanchnic nerves synapse there then join the abdominal aortic plexuses
166
what are the parasympathetic nerves
vagus nerve
pelvic splanchnic nerve s2, s3, s4
167
What is the effect of vagotomy on gastric secretion?
A vagotomy reduces gastric acid secretion by cutting the vagus nerve at the gastroesophageal junction, which reduces the nervous stimulation of the parietal cells.
severe gastric peptide ulcer disease
168
Referred pain of the gut region
The foregut tends to refer to the epigastric region. The midgut tends to refer to the umbilical region and the hindgut tends to refer to the suprapubic region.
169
Referred pain is the reason why appendicitis pain is often initially described as an epigastric/umbilical pain. When the appendix is inflamed...
it then touches the peritoneum causing the pain to localise to the left iliac fossa.
170
