Biology Flashcards
Stem cells
Unspecialised cells that can develop into many other types of cells
What do stem cells differentiate into
All types of cells in the body
Sex cell, muscle cell, fat cell, immune cell, epithelial cell, nervous cell, blood cell, bone cell
Function of Villi
Provides the small intestine with a large surface area so more digested food can be absorbed into the bloodstream
Good blood supply
Villi
Tiny projections which cover the inside of the small intestine
Microvilli
Microscopic cellular membrane protusions that increase the surface area for diffusion
Does villi use diffusion or osmosis
Diffusion
Nutrients which diffuse
Where is amylase produced
Pancreas and salivary glands
Where is lipase produced
Pancreas, mouth and stomach
Function of lipase
Break down fats in food so they can be absorbed in the intestines
Where is protease produced
Stomach, pancreas and small intestine
Protease function
Regulates the fate, localization, and activity of many proteins
Starch test
Few drops of iodine on food solution
If food solution turns blue-black starch is present
Lipid test
Few drops of ethanol to food solution
If solution turns cloudy it has lipids
Sugar test
Few drops of benedict’s solution
If solution turns green contains some sugar
If orange-red it contains lots of sugar
Protein test
Few drops of biuret solution
If purple contains protein
Transpiration
When plants take up water from the soil and release water vapor into the air from their leaves
How to do food tests
Crush food using a pestle and mortar
Add a few drops of distilled water
Filter contents of the mortar through the funnel and filter paper into a boiling tube
Amylase function
Amylase and maltase mixtures break down starch into glucose in the mouth and small intestine
Compare biological and mechanical heart
Mechanical valves last a lifetime but have increased risk of blood clots
Biological valves do not increase risk of either bleeding or clotting but will wear out sooner
