Week 10: Gastrointestinal System

Question 1

what is the opening and termination of the alimentary cana/GI system?

Answer 1

opening - mouth
termination - anal canal

Question 2

2 main roles of the digestive system?

Answer 2

digestion (processing food)
absorption (transfers nutrients to circultion)

Question 3

2 groups of organs in the GI system?

Answer 3

digestive tract
accessory organs

Question 4

name accessory organs of the GI system?

Answer 4

salivary glands
gallbladder
liver
pancreas

Question 5

what secretions do the salivary glands produce?

Answer 5

serous/watery secretion
mixed seromucous secretion - mixed watery and mucus
mucous secretion

Question 6

functions of saliva?

Answer 6

buffer mouth pH
protects surface of mouth and gut
antimicrobial action
maintains tooth structure
aids with taste
small amount of digestion help

Question 7

function of gall bladder?

Answer 7

stores and concentrates bile

Question 8

bile function?

Answer 8

fat digestion

Question 9

where is bile produced?

Answer 9

liver

Question 10

name the parts of the GI tract in order?

Answer 10

oral cavity
pharynx
oesophagus
stomach
small intestine
large intestine

Question 11

function of pharynx?

Answer 11

food and air passes through

Question 12

where is the oesophagus found?

Answer 12

pharynx to stomach
passes behind heart and trachea

Question 13

functions of the stomach?

Answer 13

churns food/drink
secretes acid and enzymes to begin digestion

Question 14

what digestion does the saliva do?

Answer 14

amylase does starch digestion

Question 15

3 parts of the small intestine?

Answer 15

duodenum
jejunum
ileum

Question 16

which secretions are present in the duodenum? main function?

Answer 16

more digestion, less absorpion
secretions from pancreas
bile

Question 17

how does the pancreas maintain an alkaline pH?

Answer 17

secretes bicarbonate rich fluids

Question 18

where does undigested material from the ileum move into?

Answer 18

large intestine

Question 19

name parts of the large intestine?

Answer 19

caecum
ascending, transverse and descending colon
rectum
anus

Question 20

name the layers of the GI tract histology.

Answer 20

mucosa
submucosa
muscularis propira
adventitia
serosa

Question 21

how is GI tract stained?

Answer 21

Haemotoxylin and eosin

Question 22

what does the mucosa line?

Answer 22

cavities of body and surface of internal organs

Question 23

what is the lamina propira? function? hat cells does it contain?

Answer 23

thin layer of loose connective tissue beneath epithelium
support and provudes nutrients for overlying epithelium
inflammatory cells

Question 24

structure of muscularis mucosae?

Answer 24

smooth muscle

Question 25

structure of submucosa? what cells does it contain?

Answer 25

dense irregular connective tissue blood vessels, nerves, lymphatic vessels

Question 26

2 layers of muscularis propira? function?

Answer 26

inner circular muscle outer longitudinal muscle both smooth muscle peristalsis - movement of food and products of digestion

Question 27

what is adventitia?

Answer 27

outer layer of fibrous connective tissue surrounding an organ oral cavity, upper end of oesophagus in chest, ascending/descending colon, rectum

Question 28

what is serosa?

Answer 28

reduces friction in parts of GI tract without adventitia

Question 29

what epithelia is in the oesophagus?

Answer 29

stratified squamous

Question 30

where are glands found in the oesophagus?

Answer 30

submucosa

Question 31

what epithelia is in the stomach onwards?

Answer 31

simple columnar

Question 32

what glands are in mucosa of stomach?

Answer 32

gastric glands for stomach secretions

Question 33

what are meissners and auerbachs plexus? where are they found?

Answer 33

nerve plexuses m - submucosa a - between circular and longitudinal muscle

Question 34

why are villi in small intestine?

Answer 34

increase surface area

Question 35

function of brunners glands in duodenum? where are they found?

Answer 35

secrete bicarbinate ions to neutralise acid from stomach submucosa

Question 36

function of peyers patches?

Answer 36

lymphoid follicles prevent growth of dangerous bacteria

Question 37

where are crypts found in small intestine?

Answer 37

jejunum

Question 38

3 parts of pharynx?

Answer 38

nasopharynx oropharynx laryngopharynx

Question 39

epiglottis function?

Answer 39

elastic cartilage covering trachea preventing food entering lungs

Question 40

what types of muscle are in each regions of the oesophagus?

Answer 40

upper 1/3 - skeletal middle 1/3 - mixed lower 1/3 - smooth

Question 41

what are verticle lines of abdomen called?

Answer 41

mid clavicular lines

Question 42

what is upper horizontal line of abdomen called?

Answer 42

subcostal line

Question 43

what is lower horizontal line of abdomen called?

Answer 43

intertubercular line

Question 44

what is in right hypochondrium of abdomen(1)?

Answer 44

liver

Question 45

what is in the epigastric region of the abdomen (2)?

Answer 45

duodenum liver gallbladder pancreas stomach

Question 46

what is in the left hypochondrium of the abdomen (3)?

Answer 46

spleen and stomach

Question 47

what is in right lumbar (4) region of abdomen?

Answer 47

ascending colon kidney

Question 48

what is in umbilical region of abdomen (5)?

Answer 48

stomach pancreas duodenum transverse colon kidneys

Question 49

what is in left lumbar region of abdomen (6)?

Answer 49

descending colon left kidney

Question 50

what is in right iliac fossa region of abdomen (7)?

Answer 50

caeceum appensix ascending colon

Question 51

what is in hypogastrium region of abdomen (8)?

Answer 51

bladder uterus ileum

Question 52

what is in left iliac fossa region of abdomen (9)?

Answer 52

sigmoid colon descending colon

Question 53

what is fundus of stomach?

Answer 53

where air collects

Question 54

what is cardia in stomach?

Answer 54

next to heart

Question 55

what is anterior and superior to the stomach?

Answer 55

lower ribs/diaphragm liver

Question 56

what attaches to the greater curvature of the stoach

Answer 56

fatty tissue/greater omentum

Question 57

function of pyloric sphincter?

Answer 57

controls entry of secretions from stomach into duodenum

Question 58

what is pyloric stenosis? what does it present with?

Answer 58

thickening/narrowing of pyloric sphincter prevents chyme passing to duodenum usually in newborns projectile vomiting without bile

Question 59

what breaks down ingestions in the stomach?

Answer 59

enzymes and hydrochloric acid

Question 60

function of rugae in stomach?

Answer 60

folds of organ help increase surface area

Question 61

what is the 3 muscular layers in the stomach?

Answer 61

muscularis propira oblique muscle layer muscularis externa

Question 62

function of muscular layers in stomach?

Answer 62

mix chyme together

Question 63

function of endocrine cells?

Answer 63

produce gastrin

Question 64

function of gastrin?

Answer 64

stimulates parietal cells to produce hydrochloric acid

Question 65

what do chief cells produce?

Answer 65

pepsinogen

Question 66

function of hydrochloric acid?

Answer 66

breaks down pepsinogen to pepsin

Question 67

function of muscus in GI system?

Answer 67

protect mucosa

Question 68

what common bile duct does the duodenum recieve?

Answer 68

sphincter of oddi recieves bile and pancreatic fluid

Question 69

where does the duodenum end?

Answer 69

duodenojejunal junction

Question 70

what does the serosa hold the small intestine on to? what is it composed of?

Answer 70

hold to mesentery 2 layers of mesothelium

Question 71

what is the mesentery?

Answer 71

organ attaching intestines to abdominal wall

Question 72

what are plica?

Answer 72

folds in small intestine similar to rugae

Question 73

2 broad functions of pancreas?

Answer 73

hormonal and digestive

Question 74

what does the exocrine gland produce in pancreas? how much of pancreas does this make up?

Answer 74

99% digestive enzymes to break down fat/carbs/protein bicarbonate ions

Question 75

what is the endocrine portion of pancreas called?

Answer 75

islets of langerhans

Question 76

what 3 hormones does pancreas produce?

Answer 76

insulin glucagon somastostatin

Question 77

function of insulin?

Answer 77

promotes glucose absorption from blood into liver, skeletal muscle and fat cells allows conversion to glycogen e.g. storage of glucose

Question 78

function of glucagon?

Answer 78

converts stored glycogen into glucose to help slow down digestive process

Question 79

function of somastostatin?

Answer 79

reduces acid secretion slows down digestive process

Question 80

what is the largest gland of the body and heaviest of heart?

Answer 80

liver

Question 81

how many lobes does the liver have?

Answer 81

4

Question 82

what is the liver covered by?

Answer 82

lower ribs and costal cartilages

Question 83

what colour is the liver?

Answer 83

red-brown

Question 84

functions of liver?

Answer 84

- produces bile - detoxifies and processes everything absorbed from GI tract - regulates glucose in blood - synthesises proteins e.g. clotting factors - inactivates hormones and drugs and insulin - drug metabolism

Question 85

when can drug metabolism be negative to the liver?

Answer 85

when metabolis is more toxic than initial compound

Question 86

what is the dual supply to the liver?

Answer 86

hepatic portal vein from gut and spleen hepatic arteries

Question 87

what provides oxygen to liver?

Answer 87

hepatic arteries

Question 88

what carries bile from the liver to the gall bladder?

Answer 88

common heptic duct

Question 89

what forms the extraheptic ducts?

Answer 89

intrahepatic ducts

Question 90

function of caecum? where is it?

Answer 90

between ileum and ascending colon reservoir for chyme

Question 91

when can the caecum be palpated?

Answer 91

faeces inflammation pregnancy

Question 92

what is the ileocaceal valve? where is it?

Answer 92

between ileum and caecum prevents reflux of large bowel contents into ileum during peristalsis

Question 93

when does the colon become sigmoid colon?

Answer 93

when it begins to turn medially

Question 94

what is the hepatic flexure?

Answer 94

when colon meets right lobe of liver and turns 90 degrees - start of transverse colon

Question 95

what is the splenic flexure?

Answer 95

when the colon turns 90 degrees to turn inferiorly

Question 96

what is the taenia coli?

Answer 96

incomplee layers of longitudinal muscle 3 longitudinal bands of smooth muscle outside of colon

Question 97

what is haustra?

Answer 97

ring like circular muscle in inner muscular layer of colon

Question 98

whar is appendice epiploicae?

Answer 98

pouches of peritoneum filled with fat mainly on transverse are sigmoid colon but not rectum

Question 99

function of goblet cell in GI tract?

Answer 99

produce mucus absorbs fluid from GI tact

Question 100

3 main vessels of blood supplying GI tract?

Answer 100

coeliac trunk/foregut superior mesenteric artery (midgut) inferior mesenteric artery/hindgut

Question 101

what does the foregut/coeliac trunk supply?

Answer 101

lower oesophagus stomach liver spleen first half of duodenum

Question 102

what does the midgut/superior mesenteric artery supply?

Answer 102

last half of duodenum jejunum ileum caecum appendix ascending colon first half transverse colon

Question 103

what does the hindgut/inferior mesenteric artery supply?

Answer 103

last 1/3 transverse colon descending colon sigmoid colon rectum

Question 104

what is portal venous drainage for?

Answer 104

gut and spleen

Question 105

what drains the lower limb?

Answer 105

femoral veins

Question 106

what drains the pelvis?

Answer 106

internal iliac veins

Question 107

what drains the kidneys?

Answer 107

renal veins

Question 108

what is the main vein draining the liver?

Answer 108

hepatic vein

Question 109

what is dysphagia?

Answer 109

difficulty swallowing

Question 110

what does too little nutrients cause?

Answer 110

malnutrition

Question 111

what is in the eatwell guide?

Answer 111

5 portions fruit/veg a day potatoes bread and carbohydrates small amounts of oil and spreads dairy 2 portions fish/week little red and processed meat beans and pulses less often eat sweets/ice cream/chocolate 6-8 glasses water a day

Question 112

function of carbohydrate in the diet? source?

Answer 112

energy source bread, rice, pasta, cereal

Question 113

function of protein in the diet? source?

Answer 113

repair/growth meat, fish, dairy, lentils, nuts

Question 114

function of fat in the diet? source?

Answer 114

long term energy store/insulation meat, cheese, cream, fish, nuts

Question 115

function of vitamins in the diet? source?

Answer 115

A - vision (liver, sweet potato) B - vegetable C - antioxidant (citrus) D - calcium absorption (oily fish)

Question 116

function of minerals in the diet? source?

Answer 116

ca - bone mineralisation (milk) iron - oxygen transport (red meat) potassium - banans

Question 117

function of fibre in the diet? source?

Answer 117

effective bowel function plants

Question 118

what is triglycerides composed of?

Answer 118

glycerol + 3 fatty acids 90% of fat in diet

Question 119

name 3 dietary fats?

Answer 119

triglycerides phospholipids cholesterol

Question 120

function of cholestrol?

Answer 120

synthesises estrogen and testosterone and bile salts present in plasma membreane

Question 121

structure and function of phospholipids?

Answer 121

2 fatty acid chains and glycerol in plasma membrane

Question 122

sources of saturated dietary fats?

Answer 122

animal foods meat fat butter cheese cream

Question 123

sources of unsaturated dietary fats?

Answer 123

planst olive and rapeseed nuts

Question 124

sourcesof cholestrol?

Answer 124

plants and animals dairy products palm and coconut oil

Question 125

how many essential amino acids are there? what does this mean?

Answer 125

9 cant be produced by the body and must be obtained from diet

Question 126

sources of dietary protein?

Answer 126

meat dairy eggs pulses nuts seeds

Question 127

examples of monosaccharides?

Answer 127

glucose fructose galactose

Question 128

name 3 disacharides?

Answer 128

sucrose maltose lactose

Question 129

what is sucrose made from?

Answer 129

glucose and fructose

Question 130

what is maltose made from?

Answer 130

glucose x 2

Question 131

what is lactose made from?

Answer 131

glucose and galactose

Question 132

what are disaccharides and polysaccharides joined by?

Answer 132

glycosidic bonds

Question 133

name a polyaccharide and its composition?

Answer 133

starch amylose and amylopectin

Question 134

what is fibre made of?

Answer 134

cellulose from plant material

Question 135

how much calories should men and women eat?

Answer 135

men - 2500 cal women - 2000 cal

Question 136

how is obesity caused?

Answer 136

dietry intake excedds energy expenditure

Question 137

how are carbohydrates (polysaccharides) digested?

Answer 137

disaccharide then monosaccharide

Question 138

how are proteins digested?

Answer 138

peptide then amino acids

Question 139

how are triglycerides digested?

Answer 139

free fatty acid diacylglycerol monoacylglycerol glycerol

Question 140

what is digestion?

Answer 140

food is broken down into components simple enough to be absorbed in the inetstine

Question 141

which enzymes carry out digestion?

Answer 141

glandular cells (mouth) secrete saliva chief cells (stomach) exocrine cells (pancreas) enzymes bound to apical membrane of enterocytes (in intestine)

Question 142

where is saliva produced?

Answer 142

parotid salivary gland submandibular salivary gland sublingual salivary gland

Question 143

functions of saliva?

Answer 143

moistens food starts digestion of carbohydrates by a-amylase produces lingual lipase to start digestion of lipids

Question 144

how does hcl produce pepsin?

Answer 144

unfolds pepsinogen and cleaves it to produce pepsin

Question 145

what is a zymogen?

Answer 145

an inactive precursor thay are activayed by cleavge of peptide bonds

Question 146

how does bile make fat accessible for enzymes?

Answer 146

it emulsifies it

Question 147

how does the liver aid absorption of fats?

Answer 147

forms micelles

Question 148

what are bile salts synthesised from? what are they converted to?

Answer 148

cholestrol converted to: cholic acid chenodeoxycholic acid

Question 149

what are bile salts conjugated with? what do they then become?

Answer 149

amino acid - glycine or taurine ampipathic , cholestrol hydrophobic, AA is hydrophilic

Question 150

functions of bile?

Answer 150

emulsifies liquid aggregates solubilisation and transport of lipids in aqueous environment

Question 151

outline functions of duodenum, jejunum, ileum

Answer 151

duodenum - mixing secretions from pancreas, liver and duodenum with food - neutralisation of food - digestion - absorption jejunum - completes breakdown - nutrient absorption ileum - nutrient absorption

Question 152

function of enterokinase? where is it found?

Answer 152

protease activating trypsin from cleaving trypsinogen duodenum

Question 153

function of trypsin?

Answer 153

cleaves zymogens to activate them procarboxypeptidase to carboxypeptidase chymotrypsinogen to chymotrypsin

Question 154

name brush border enzymes? where are they found? function?

Answer 154

peptidases lactase sucrase maltase tethered to plasma membrane in small intestine cleave peptides to amino acids

Question 155

name 3 dietary macromolecules?

Answer 155

fats proteins carbohydrates

Question 156

why are macromolecules diested as zymogen sometimes?

Answer 156

to prevent autodigestion

Question 157

what is mastication? what does the food tyrn into?

Answer 157

breaks up food and moistens it bolus

Question 158

what happens to carbohydrates, proteins and lipids in the mouth?

Answer 158

carbs - starch broken down by a-amylase to maltotriose, maltose and a-limit dextrin proteins - nothing lipids - lingual lipase present but minor contribution

Question 159

what happens to carbohydrates, proteins and lipids in the stomach?

Answer 159

carbs - nothing as a-amylase not activated proteins - hcl denatures proteins and activates pepsin - endopeptidase cleaving proteins to smaller peptides lipids - gastric acid present but minor composition

Question 160

what happens to carbohydrates, proteins and lipids in the duodenum?

Answer 160

carbs - a-amylase further digests starch, brush border disaccharides - result in monosaccharides proteins - cleaved by trypsin, chymotrypsin, elastase, carboxypeptidases to produce increasingly smaller peptides, brush border peptidases produce dipeptides/amino acids lipids - pancreatic lipase digests to monoglycerides and fatty acids phospholipase digests phospholipids to lysolecithin and fatty acids

Question 161

3 types of absorption?

Answer 161

passive (diffusion) - slow, needs conc gradient facilitated transport - faster, membrane carrier, controllable active transport - uses atp, fast, uses membrane carrier, controllable

Question 162

draw a micelle

Answer 162

Question 163

what are the aims of scientific research in medicine?

Answer 163

- diagnosis of conditions and disease - causitave links between lifestyle and disease - preventative methods - slowing disease progression or reoccurance

Question 164

what is evidence-based medicine?

Answer 164

the integration of best research evidence with clinical expertise and care of individual patients BEST RESEARCH PATIENT CONCERNS CLINICAL EXPERTISE

Question 165

what does qualitative research involve?

Answer 165

- observational studies - interview/focus groups/questionnaires - e.g. patient experince of living with condition disease, how do patients feel about their care/treatment

Question 166

what does quantitative research involve?

Answer 166

- experimental or observational - generating numerical data - statistical analysis - what is the effect of intervention on comparable groups - does using a nicotine inhaler reduce smoking long term?

Question 167

What are observational studies? When are they used? which type of study is used?

Answer 167

- Collect info about patients without trying to influence their exposure to a treatment/intervention that may prevent disease - used when experimentation intervention is unethical to implement or when it is not appropriate to generalise - case-control, cohort study - may provide evidence of linkage with further investigation required

Question 168

What are experimental studies? what do they compare? which type of study is used?

Answer 168

- assign the exposure or intervention to individuals or groups - compare the outcomes in a group of patients with those from a comparable control group - randomised controlled trials

Question 169

What is meta-analysis?

Answer 169

pooling of data from several randomised controlled trials for statistical analysis to give greater confidence in the conclusions of the review

Question 170

what are randomised controlled trials?

Answer 170

number of similar people are randomly assigned to 2 or more groups to test a specific drug, treatment or type of intervention

Question 171

what are systemic review of cohort studies?

Answer 171

critical assessment and evaluation of existing cohort or case study

Question 172

what are cohort studies?

Answer 172

participants classify whether they have been exposed to something of interest e.g. smoking - look back at patient records to determine natural history of a condition - follow participant population over time to observe progression of condition/disease

Question 173

what are case-control studies?

Answer 173

participants selected by whether ot not they have condition/disease may estimate strength of association with a predictor

Question 174

what are case series?

Answer 174

most basic type of study describes medical history of single patient by one or more clinicians

Question 175

what are the strongest and weakest research study types?

Answer 175

stongest: meta-analysis weakest - case series

Question 176

what type of study is a randomised controlled trial?

Answer 176

quantitative measures outcomes after participants recieve intervenion

Question 177

describe what happens in a randomised controlled trial

Answer 177

- experimental group recieves intervention - comparison/control group recieves alternative e.g. placebo/standard treatment or nothing - groups are followed up to assess effectiveness of intervention - difference in response assessed statistically

Question 178

what is a RCT based on?

Answer 178

precise question or hypothesis to be tested

Question 179

what should be considered regarding selection criteria in RCT?

Answer 179

age sex geographical location social/occupational groups

Question 180

what is eligibility criteria in RCT? what considerations are there?

Answer 180

clearly defined inclusion and exclusion criteria - potential for effect of intervntion - ability to detect effect - participant safety abilty of patients to give informed consent

Question 181

what is included in estimate of sample size in an RCT?

Answer 181

- enough participants to answer question - shouldnt enrol more participants than needed - sample size calculated with guidleines

Question 182

how should bias be minimised in an RCT

Answer 182

randomise participants and those involved in research are blinded

Question 183

what is random sampling? how can this be ensured?

Answer 183

sampling target population where each member of population has an equal chance of being selected - characteristics of random sample should be similar to population of whole - target group identified - random selection of people invited to participate

Question 184

what is random allocation/randomisation?

Answer 184

assigning people in a research study to different groups without taking similarities/differences between them into account - everyone has equal chance of allocation to each group - uses computer generated random sequence - cant attribute differences to bias

Question 185

what is a placebo?

Answer 185

fake treatment given to patients in control group of clinical trial indistinguishable from actual treatment

Question 186

what is placebo effect?

Answer 186

beneficial effect produced by placebo treatment which cannot be attributed to properties of placebo itself patient recieve improvement in symptoms from physiological effect of recieving treatment and not actual treatment

Question 187

what is blinding? what does this do?

Answer 187

ensures participants/investigators in RCT are unaware of elemnt of study e.g. group allocation increases validity of trial

Question 188

how is blinding achieved in RCT?

Answer 188

use of identical tablets, drug containers, administration methods for interventions and control groups conceal of group/patient for analysis

Question 189

what is single blinding?

Answer 189

patient unaware of type of treatment/intervention they are recieving

Question 190

what is double blinding?

Answer 190

patient and investigatiors unaware of treatement/investigation being recieved

Question 191

what is triple blinding?

Answer 191

patient, investigator and data analysist are unaware of treatment/intervention being recieved ensure data analysis is objective reduces influence of placebo effect

Question 192

what is attrition?

Answer 192

participant drop out over time due to death, migration, loss of interest

Question 193

what do positive follow up results of RCT show?

Answer 193

benefits of intervention reduced disease severity/cost to health service in study group

Question 194

what do negative follow up results of RCT show?

Answer 194

adverse effects observed - may halt trial early severity and frequency of abserved side effects

Question 195

2 things RCTs may suffer from?

Answer 195

noncompliance missing outcomes

Question 196

what is noncompliance in RCT?

Answer 196

patients not adhering to protocol

Question 197

what is missing outcomes in RCT?

Answer 197

participants lost to follow up, outcomes are missed

Question 198

what is intention to treat analysis?

Answer 198

solution to noncompliance and missing outcomes in RCT

Question 199

what is intention to treat analysis? what must you always report?

Answer 199

ignoring noncompliance/protocol deviation/withdrawal after randomisation follow up with patients withdrawn from study include all subjects in groups they were randomly allocated to once randomised, always analysed report any deviations or missing responses

Question 200

why do you use confidence intervals in RCT?

Answer 200

assess evidence for a difference in outcome between groups

Question 201

what are confidence intervals?

Answer 201

range of values that has specified probaility of containing true population parameter provides confidence level

Question 202

what is number needed to treat?

Answer 202

average number of patients who need to recieve treatemnt for one of them to get positive outcome in time specified closer NNT-1 more effective the trearment

Question 203

what is number needed to harm?

Answer 203

measure of chance of experiencing harm in a specified time becase of the treatment or other intervention should be as large as possible

Question 204

what is a RCT superiority trial?

Answer 204

aims to show that a new intervention is more effective than the compartivie treatment - placebo or current best treatment most clinical trials

Question 205

what is a RCT equivalnce trial?

Answer 205

prove that 2 drugs have same clinical benefit demonstrates that effect of new drug differs from effect of current treatment that is clinically unimportant

Question 206

what is a RCT non-inferiority study?

Answer 206

aims to show that effect of new treatment cannot be said to be significantly weaker than current treatment

Question 207

advantages of RCT?

Answer 207

- randomisation produces valid statistical tests - gold standard to asses cause and effect - produces comparable groups

Question 208

disadvantages of RCT?

Answer 208

- costly and time consuming and difficult to run - recruitment may be difficult - difficult to administer - study may not represent general population

Question 209

what happens if fatty acids are less than 12 carbons long?

Answer 209

they go straight to the portal blood

Question 210

what happens if fatty acids are more than 12 carbons long?

Answer 210

triglyceride reformed into protein/lipid structyre called chylomicron

Question 211

what is the hepatic portal vein?

Answer 211

blood vessel carrying blood from GI tract to the liver

Question 212

what are nutrients essential for?

Answer 212

producing energy in the body

Question 213

what is the first law of thermodynamics?

Answer 213

energy can neither be created nor destroyed it is trasnferred from one form to another, or one place to another

Question 214

how is chemical energy derived for humans to maintain a steady state?

Answer 214

food

Question 215

what is metabolism?

Answer 215

the sum of all chemical reactions in which energy is made available and consumed in the body

Question 216

what is the bodys chemical waste?

Answer 216

carbon dioxide water

Question 217

what are catobolic pathways?

Answer 217

complex molecules broken down into smaller ones: energy released

Question 218

what are anabolic pathways?

Answer 218

more simple molecule converted into a more complex molecule using energy

Question 219

what is energy used for in the body?

Answer 219

- contraction of muscle and hence all movement (skeletal, cardiac, smooth muscle of the gut and blood vessels etc.) - accumulation of ions against concentration gradients e.g. for nerve impulse transmission - biosynthesis: building of tissues - waste disposal - generation of heat

Question 220

when is gibbs free energy positive?

Answer 220

product contains more energy than the substrate so energy is required

Question 221

when is gibbs free energy negative?

Answer 221

product contains less energy than the substrate so energy is lost

Question 222

how do cells harness lost energy?

Answer 222

ATP

Question 223

exergonic vs endergonic reactions?

Answer 223

exergonic - energy is lost endergonic - energy is required

Question 224

how much energy is give out per mole of ATP, and what is this figure within cells?

Answer 224

30kj/mole of atp 50kj/mole of atp in cells

Question 225

why must cells have their own capacity to make atp?

Answer 225

atp cannot be transferred between cells

Question 226

Name each part of this ATP

Answer 226

yellow - phosphate group pink - ribose orange - adenine

Question 227

what happens when phosphate bonds are broken in ATP and why?

Answer 227

phosphate groups are held together by high energy bonds - they dissipate energy when broken

Question 228

what are the products of ATP hydrolysis?

Answer 228

pi + adenosine diphosphate + energy

Question 229

why is atp broken down and when is it remade?

Answer 229

broken down - for energy for cellular work remade - from energy from catabolism

Question 230

what is catabolism?

Answer 230

set of metabolic pathways breaking down molecules into smaller units, produces energy

Question 231

how much ATP is turned over every day?

Answer 231

80KG

Question 232

what are food macromolecules broken down into?

Answer 232

glucose fatty acids amino acids

Question 233

how is Acetyl CoA produced from; - glucose? - fatty acids? - amino acids?

Answer 233

1. glycolysis 2. beta oxidation 3. transamination, oxidative deamination

Question 234

what does acetyl coa synthesise?

Answer 234

metabolites

Question 235

what cycle does acetyl coa contribute to?

Answer 235

TCA/krebs cycle

Question 236

why is the TCA cycle called an amphibolic process?

Answer 236

has anabolic and catabolic components

Question 237

what 3 macromolecules produce acetyl CoA?

Answer 237

carbohydrate fat protein

Question 238

2 phases of TCA cycle?

Answer 238

decarboxylating reductive

Question 239

outline how the TCA cycle begins

Answer 239

Acetyl CoA enters TCA cycle and condenses with oxaloacetate to form citrate

Question 240

how many carbons does: - acetyl coa - oxeloacetate - citrate - succinyl coa have?

Answer 240

1. 2 2. 4 3. 6 4. 4

Question 241

what happens in decarboxylation?

Answer 241

citrate metabolised to succinyl coa - loss of 2 carbon molecules forms co2

Question 242

what happens in the reductive phase?

Answer 242

succinyl coa metabolised to oxaloacetate which is combined with another acetyl coa so tca cycle can resume

Question 243

how many atp does TCA cycle produce?

Answer 243

1 GTP

Question 244

what does TCA cycle produce?

Answer 244

1 ATP 3 NADH 1 FADH

Question 245

Which molecules from TCA cycle feed into electron transport chain?

Answer 245

nadh and fadh

Question 246

what happens in the electron transport chain?

Answer 246

four protein complexes pump protons across the inner mitochondrial membrane from mitochondrial matrix to intermembrane space

Question 247

how is the differential proton concentration achieved in the mitochondria? where are most protons found?

Answer 247

protons pumped across membrane to maintain electrochemical gradient more protons in intermembrane space as inner membrane is very impermabel

Question 248

how are protons able to be pumped across the membrane?

Answer 248

NADH and FADH protons and electrons

Question 249

where does NADH enter the ETC? what does it donate?

Answer 249

complex one donates 2 electrons and 1 proton

Question 250

what happens to electrons donated by NADH in ETC?

Answer 250

pass along redox centres in protein complexes

Question 251

what are redox centres?

Answer 251

places where reduction and oxidation reactions occur

Question 252

how are electrons passed along redox centres?

Answer 252

each protein complex has an increased affinity for electrons

Question 253

how are electrons passed from complex one to three?

Answer 253

co enzyme q

Question 254

how are electrons passed to complex four?

Answer 254

cytochrome c

Question 255

which protein complexes pump protons into the intermembrane space?

Answer 255

1,3,4

Question 256

what is the function of complex 2 in the ETC?

Answer 256

where FADH enters produces atp encourages oher complexes to pump protons across the membrane

Question 257

what allows protons back into the mitochondrial matrix in the ETC? how?

Answer 257

atp synthase as protons enter the ATP synthase rotates and converts ADP + Pi = ATP

Question 258

What is the main generator of ATP in thw ETC?

Answer 258

ATP synthase

Question 259

what happens when electrons reach the end of complex 4 in the ETC?

Answer 259

they are donated to molecular oxyegn along with a proton to make water

Question 260

why can RBCs not do the ETC?

Answer 260

it requires mitochondria and oxygen

Question 261

what is GTP produced by in the TCA?

Answer 261

substrate level phosphorylation: ATP not produced in the ETC/oxiditivate phosphorylation

Question 262

how much atp is produced from 1 NADH oxidised by the ETC? why?

Answer 262

2.5 it enters the complex at prtein 1

Question 263

how much atp is produced from 1 FADH oxidised by the ETC?

Answer 263

1.5

Question 264

how much ATP altogether produced by 1 Acetyl CoA in TCA cycle?

Answer 264

10atp

Question 265

what is the end product of glycolysis?

Answer 265

2 pyruvate

Question 266

what is glycolysis?

Answer 266

carbohydrate catabolism/breakdown 6 carbon glucose to 2x3 carbon pyruvate molecules

Question 267

where does glycolysis occur? benefit of this?

Answer 267

cytosol of all cells cells without oxygen/mitochondria can produce atp

Question 268

What happens in ATP investment phase of glycolysis?

Answer 268

6 carbon glucose molecule broken down to 2x3 carbon glyceraldehyde 3 phosphate molecules 2 ATP required, 2 ADP produced

Question 269

what happens in energy generation stage of glycolysis?

Answer 269

4 ADP required to produce 4 ATP 2 pyruvate are produced 2 NAD+ produce 2 NADH

Question 270

what happens under anaerobic conditions after glycolysis?

Answer 270

pyruvate converted to lactate this regenerates NAD+ to keep glycolysis going

Question 271

what happens to NAD+ if pyruvate is made infinitely?

Answer 271

NAD+ will run out glycolysis wont take place cell death will occur due to lack of energy supply

Question 272

how can NAD+ be regenerated?

Answer 272

NADH is oxidised to remove a proton achieved by fermentation of pyruvate into lactate

Question 273

what is the overall equation for anaerobic glycolysis?

Answer 273

glucose + 2ADP + 2pi = 2 lactate + 2 ATP

Question 274

Whta happens to pyruvate from glycolysis under aerobic conditions? how?

Answer 274

pyruvate transported to mitochondrion and converted to acetyl-coa by pyruvate dehydrogenase

Question 275

how is acetyl coa formed from pyruvate?

Answer 275

3C pyruvate loses a carbon atom which produces CO2

Question 276

What TCA component is formed in aerobic glycolysis?

Answer 276

NADH - fed into TCA cycle

Question 277

what is the equation for aerobic glycolysis?

Answer 277

pyruvate + NAD+ + pyruvate dehydrogenase = acetyl coa + co2+ NADH

Question 278

How many round of TCA cycle can occur for every glucose molecuke?

Answer 278

2

Question 279

What is glucose used for in the body?

Answer 279

energy source

Question 280

where is glucose stored in the body?

Answer 280

stored as glycogen mainly in liver but also in muscle

Question 281

what happens if you fast for 12-24 hrs?

Answer 281

you will run out of glucose stores and the body changes to lipid metabolism

Question 282

how are fats stored in adipose tissue?

Answer 282

triglycerides

Question 283

how are triglycerides released from adipose tissue?

Answer 283

lipase enzymes

Question 284

what happens when lipase release triglycerides from adipose tissue?

Answer 284

broken down to glycerol + fatty acids transported in the blood via plasma proteins albumin to protect them from water taken up into cells for oxidation

Question 285

what is oxidation?

Answer 285

when an atom, molecule or ion loses one or more electrons in a chemical reaction

Question 286

where are all enzymes required for fatty acid catabolism found?

Answer 286

matrix of mitochondria

Question 287

how much atp does modification of fatty acids require?

Answer 287

2 atp

Question 288

how is fatty acid modified to cross inner mitochondrial membrane?

Answer 288

acetyl coa and 2 atp convert it into fatty acyl coa

Question 289

why is a carnitine shuttle used? what happens?

Answer 289

coa on fatty acyl coa is replaced with carnitine coa cannot cross inner mitochondrial membrane

Question 290

what happens after carnitine shuttle?

Answer 290

fatty acyl caritine enters trasnporter protein in inner mitochondrial membrane

Question 291

what happens when fatty acyl carnitine is in the mitochondrial matrix?

Answer 291

caritine removed and replaced by coa so fatty acyl coa can be metabolised and undergo fatty acid degregation

Question 292

what is the only fatty acid able to be metabolised?

Answer 292

fatty acyl coa

Question 293

how is fatty acyl coa metabolised?

Answer 293

beta oxidation

Question 294

how does beta oxidation produce acetyl coa?

Answer 294

cleaves carbon backbone of fatty acids between alpha and beta carbons

Question 295

what does each beta oxidation produce?

Answer 295

1 NADH and 1 FADH to feed into ETC

Question 296

what is an amine group?

Answer 296

NH2

Question 297

what is transamination?

Answer 297

removing an amine group from an amino acid and trasnferring it to a keto acid

Question 298

what keto acid is usually involved in transamination?

Answer 298

aplha ketoglutarate

Question 299

what does a keto acid do in transamination?

Answer 299

transfers ketone group to original amino acid new amino acid and keto acid are formed

Question 300

what are common amino acids in transamination?

Answer 300

glutamate alanine asparate

Question 301

what would alanine produce in transamination?

Answer 301

pyruvate

Question 302

what would asparate produce in transamination?

Answer 302

oxaloacetate

Question 303

what is deamination?

Answer 303

catabolism of amino acids where amine group is removed

Question 304

where does deamination take place? what side product is produced when amine group is removed?

Answer 304

liver ammonium - neurotoxic and must be removed by cells

Question 305

what is ammonium converted to?

Answer 305

urea - expelled by kidneys

Question 306

why is removal of amine groups important?

Answer 306

releases carbon backbone of amino acid and can be regenerated to glucose, fatty acids or krebs cycle intermediates

Question 307

2 classifications of amino acids?

Answer 307

glucogenic ketogenic

Question 308

what breakdown products are produced by glucose?

Answer 308

pyruvate oxaloacetate intermediated of TCA

Question 309

what breakdown products are produced by ketogenic fatty acids?

Answer 309

acetyl coa acetoacetyl coa

Question 310

what are 2 true ketogenic fatty acids?

Answer 310

leucine lysine

Question 311

what is gluconeogeneiss?

Answer 311

production of glucose from non carbohydrate sources

Question 312

where does metabolic fuel come from in prolonged starvation?

Answer 312

glucose first and glycogen stores in liver - 16-24hrs stored fats in adipose tissue - energy reserve for 3 months protein - 14 days of energy

Question 313

why is protein conserved as an energy source in starvation?

Answer 313

so body can move around to forage for food

Question 314

what is the basal metabolic rate?

Answer 314

energy required to maintain basic functions when person is lying down and relaxed in normal temperature

Question 315

what are basic functions?

Answer 315

blood flow, breathing, digestion, brain activity

Question 316

what additional energy expensiture occurs in females?

Answer 316

pregnancy and lactation

Question 317

how much extra calories are required per day in last 3 months of pregnancy and during breast feeding?

Answer 317

800 2000

Question 318

how is BMI calculated?

Answer 318

weight in kg/height in metres squared

Question 319

when is BMI calculation limited?

Answer 319

boxers/rugby/weightlifters have higher muscle mass would make them obese when they only have extra muscle

Question 320

What symptoms are there of fatigue?

Answer 320

tiredness, lack of energy, weakness, exhaustion, sleepiness

Question 321

when can fatigueoccur?

Answer 321

when energy being ingested in less than is required

Question 322

what disorders can occur from excess fatigue?

Answer 322

chronic fatigue syndrome endocrine disorders immune deficiences

Question 323

what is the second law of thermodynamics?

Answer 323

when energy is trasnferred from one form to another you lose energy in the form of heat, depleting energy stocks in body

Question 324

what is bulimia nervosa?

Answer 324

recurrent episodes of overeating acompanied with compensatory behaviour aimed at preventing weight gain preoccupied with body shape or weight influencing self evaluation not significantly underweight

Question 325

what are compensatory behaviours in EDs?

Answer 325

exercise, laxative use, vomiting

Question 326

management of bulimia in children?

Answer 326

cognitive behavioural therapy or family based treatment adapted for bulimia fluoxetine considered with psychological therapy

Question 327

magaemnt of bulimia in adults?

Answer 327

cbt adapted for bulimia antidepressents offered with psychological treatment

Question 328

what is cognitive behavioural therapy?

Answer 328

evidence based psychological treatment for mental health problems

Question 329

how to manage binge eating disorder?

Answer 329

cbt antidepressants not recommended

Question 329

what is binge eating disorder?

Answer 329

recurrent episodes of binge eating (1x week for 3 months) not with compensatory behaviours secretively and ut of control

Question 330

what is anorexia?

Answer 330

low body weight - bmi less than 18.5 presistant pattern of behaviours to prevent restoration of normal weight low body weight central to persons self evaluation body dysmorphia

Question 331

how to manage anorexia in young people?

Answer 331

family based treatment cbt

Question 332

how to manage anorexia in adults?

Answer 332

cbt olanzapine

Question 333

why should ed treatment be accessed early e.g. first 3 years?

Answer 333

anorexia can cause death neural pathways can form

Question 334

what is arfid?

Answer 334

abnormal eating or feeding behaviours insufficent intake or variety of food weight loss and nutritional deficiencies

Question 335

what is ofsed?

Answer 335

some symptoms of different eating disirders

Question 336

complications of EDs?

Answer 336

- impaired concentration/cognitive performance - dry skin, brittle hair, hair loss - low BP, arrythmia - anaemia - impaired renal function - constipation infertility

Question 337

high risk patients in ED?

Answer 337

low bmi and rapid rate of weight loss low BP and low pulse electrolyte abnormalities liver function abnormalities

Question 338

Describe how blood would drain to heart from ileum

Answer 338

- superior mesenteric vein - portal vein then liver - detoxified then hepatic vein - ivc