Nutrition digestion and absorption 1 Flashcards
What are the 6 dietary constituents?
Water Minerals Vitamins Carbohydrates Fats Proteins
Which are the monosaccharide sugars that can cross the cell wall?
Glucose,Galactose and Fructose (All C6)
What are the 3 disaccharides and what are they made from?
What are they broken down by?
Lactose = glucose + galactose (lactase) Sucrose = glucose + fructose (sucrase) Maltose = glucose + glucose (maltase)
What links the two monosaccharides to make a disaccharide?
glycosidic bonds
What are the 2 forms of starch?
alpha-amylose: glucose linked in straight chains
amylopectin: glucose chains highly branched
What is starch made from?
What is it broken down by?
Glucose monomers linked by alpha-1,4 glycosidic bonds - hydrolysed by amylases (saliva, pancreas)
What is cellulose and how is it broken down?
Unbranched, linear chains of glucose monomers linked by -1,4 glycosidic bonds
No animal can break it down,only bacteria
In the small intestine, which transporter does glucose use to cross the cell wall?
Sodium glucose transporter proteins(SGLT1)
This is a sodium dependent transporter
What is the consequence of glucose and sodium crossing across the small intestine.
An osmotic imbalance is created, causing an osmotic pull for water.
What is the function of GLUT-2?
Transports glucose and fructose out of cells(liver,pancreatic b cells) and into the blood.
What do proteins become when they undergo post-translational modifications?
glycoproteins and lipoproteins
Which enzymes hydrolyse peptide bonds and reduce a proteins to an amino acid?
proteases and peptidases
What are the 2 end terminals of proteins?
amino terminal end the carboxy-terminal end
H2N COOH
