Alimentary Canal Pt.2 Flashcards
What are the principle dietary constituents
Proteins
Carbohydrates
Fats
Vitamins
Minerals
Water
Which nutrients are macromolecules
Proteins
Fats
Carbohydrates
Why do we store nutrients as macromolecules instead of as monomers
More monomers creates a higher osmotic pressure than a single macromolecules
Controls breakdown
What are different chains of carbohydrates called and how many are in the chain
Monosaccharides - 1 molecule
Disaccharides - 2 molecules
Oligosaccharides - 3-9 molecules
Polysaccarides - 10+ molecules
What are the three main hexoses monosaccharides and are they aldoses or ketoses
Glucose - aldoses
Galactose - aldoses
Fructose - ketoses
Are simple sugars chains or cyclical in shape
Cyclical - Carbon 1 joins to carbon 5
In hexoses what does alpha or beta mean
Alpha - OH are on the same side
Beta - OH are on opposite sides
What are the different forms of glucose
Alpha-D-glucose
Alpha-L-glucose
Beta-D-glucose
Beta-L-glucose
What is the most common form of glucose
Beta-D-glucose
What are the three main disaccharides called and what are they formed from
Glucose + glucose = maltose
Glucose + galactose = lactose
Glucose + fructose = sucrose
what bonds form between monosaccharides to make a chain
Glycosidic bonds
Which enzymes break down maltose, sucrose and lactose
Maltase
Sucrase
Lactase
People with lactose intolerance don’t have which chemical in their GIT
Lactase
sugar is instead fermented by bacterial and form acids and gases causing irritation
Name 3 polysaccharides and if they are branched
Glycogen - highly branched
Starch - moderately branched
Cellulose - unbranched
Are cellulose and starch beta or alpha bonded
Cellulose - Beta
Starch - Alpha
Why cant human or any other mammals breakdown cellulose
Amylase doesn’t breakdown beta 1,4 glycosidic bonds
Cellulose is instead considered dietary fibre (bulks up faeces)
Which enzyme breaks down starch and where can it be found
Amylase
Pancreas and salivary glands
Where on the cell are the apical and basolateral membranes found on epithelial cells
Apical membranes can be found on the top (by the lumen)
Basolateral membranes can be found on the bottom of the cell
Where are tight junctions found in the intestines
Between epithelial cells
What types of transport across the membrane are there and what type of transport is it
Paracellular (between the cells) - passive diffusion
Transcellular (passes through membranes without transporter) - passive or active
Vectoral (carrier required to cross each membrane and requires nucleus in cell - active
Is a gradient requires for glucose and galactose to pass though the membrane
What makesthe gradient
Yes
ATPase
What transporter brings Na and Glucose across the apical membrane
SGLT1
What transporter moves glucose from the cell in to the blood
GLUT2
What GLUT transporters are there and where are they found
GLUT1 - blood cells and blood brain barrier
GLUT2 - liver, pancreas, intestines and kidney
GLUT3 - brain
GLUT4 - adipose tissue and skeletal muscle (insulin dependant)
GLUT5 - sperm (transports fructose)
Does SGLT1 transport aldoses or ketoses
Aldoses - glucose and galactose
Is a gradient requires for fructose to pass though the membrane
What is it called
No
Which transporter moves fructose into the cell
GLUT5
What allows fructose to leave the cell
GLUT2
Which of the 3 simple sugars can help with rehydration
Glucose and galactose
Proteins are made up of which monomer
Amino acids
What bond joins amino acids together
What is the process called
Peptide bonds
Condensation
Which enzyme breaks down proteins
Proteases
Difference between endo and exo peptidases
Endo - breaks up with in molecule
Exo - breaks up from the edges
Are aminopeptidase and carboxypeptidases exo or endo peptidases
Exopeptidases