2 Flashcards
adaptions of alveoli (in the lungs)
Network of cappilaries which give you good blood supply (maintains concentration gradient)
Large SA
Moist
one cell thick
adaptions of Villi (small intestine)
Network of capillaries
Large SA(microvilli)
Once cell thick walls(close so there is less space to travel)
Rich blood supply(transports food molecules away and maintain diffusion gradient)
What is the meaning of dilute
mostly water in the solution
what is the meaning of concentrated
less water in the solution
What does active transport require
Energy
What are 3 things the stomach does in digestion
contracts walls so food is pushed around and mixed
produces Pepsin - breaks down protein- produces hcl which kills bacteria
produces an environment for Pepsin
How do enzymes work
substrate enters the active site of an enzyme
the enzyme then breaks down the substrate into products
products are then released from the active site
What does starch do to iodine
orange to blue black
sugars turn benedict solution
blue turns to brick red upon heating In a water bath
protein turn biurets reagent from
grind food and add biuret reagent and it goes from blue to purple
lipids turn cold ethanol to
Colourless to white precipitate
what is the enzyme practical
mix amylase and starch and start the time
remove a few drops from the mixture and add it to the spotting tile with iodine inside
at the start it will stay black but later on it will stay orange as starch has been fully digested
repeat at different temperatures
plot onto graph with time on the y axis and temperature on the x axis
what do proteins aid in
growth
what do carbohydrates do
provides energy
what do fibres do
aid in digestion