MCBG S17 Catabolism And Glycolysis Flashcards
(27 cards)
Where does stage 1 of metabolism occur? What does it involve? Are the pathways long or short? What bonds are broken? Is energy released?
GI tract - extracellularly Breakdown of macromolecules to smaller building block molecules for absorption. Short C-O and C-N - no C-C bonds No
Where does stage 2 of metabolism occur?
What does it involve?
What is made?
Oxidative or reductive?
- Cytosol or mitochondria
- Breakdown of building blocks to smaller primary metabolites
- NADH and ATP
- Oxidative
Where does stage 3 of metabolism occur? What is it called? Oxidative or reductive? Overall reaction? What does it make?
In the mitochondrial matrix TCA cycle Oxidative AcetylCoA to 2CO2 GTP, FADH2, NADH, precursors for biosynthesis.
Where does stage 4 of metabolism occur?
What is it called?
What does it involve?
Mitochondria
Oxidative phosphorylation
Reducing power (NADH,FADH2) to ATP.
What is the general formula for a carbohydrate?
(CH2O)n
What are carbohydrates that contain aldehyde or ketones called?
Aldoses
Ketoses
How many carbons can a monosaccharide have?
3-9
What is glucose concentration in the blood?
5mM
What cells have an absolute requirement for glucose?
RBCs
Neutrophils
Inner most cells of the kidney medulla
Lens of eye
What does salivary amylase break down?
Starch, glycogen to dextrins
What do pancreatic amylase breakdown?
Dextrins to monosaccharides
What type of bond can pancreatic amylase breakdown?
Alpha 1,4-glycosidic bonds
What bond does isomaltase break?
Alpha 1,6 glycosidic bond
What are the 3 main causes of lactose intolerance?
Primary lactase deficiency
Secondary ^
Congenital ^
What is primary lactase deficiency?
Does it occur in younger children?
Which areas have highest prevalence?
A sense of lactase persistence allele.
Only adults
Northwest Europe
What is secondary lactase deficiency caused by?
Injury to small intestine
- Gastroenteritis
- Coeliac disease
- Crohn’s disease
- Ulcerative colitis
What is Crohn’s disease?
Type of IBD can affect any part of GI tract from mouth to anus.
What is ulcerative colitis?
Inflammation of the colon and rectum
Small ulcers develop in the colon lining, bleed and produce pus.
What causes congenital lactase deficiency?
Autosomal recessive defect in lactase gene.
What are 5 symptoms of lactase intolerance?
- Bloating
- Cramps
- Flatulence
- Diarrhoea
- Rumbling stomach
WHere are GLUT 1, GLUT2, GLUT3, GLUT 4 and GLUT 5 found?
GLUT1= foetal tissues, RBCs, BBB GLUT2= panc B cells, SI, liver, kidney GLUT3=neurones and placenta GLUT4= adipose,striated muscle GLUT5= sperm and intestine.
What are the functions of glycolysis?
Oxidation of glucose to pyruvate
NADH production 2/ glucose
ATP - 2 net
6 and 3 C intermediates produced.
Decarboxylation occurs in glycolysis true or false?
False
What step commits glucose to glycolysis?
Step 3 PFK1
