B2 Flashcards
What are the nutrients that are found in food.
Protein: growth and repair
Carbohydrates: energy
Lipids: store of energy
All large molecules are too large too be absorbed into bloodstream so they are digested
What is digestion
Large food molecules are broken down into smaller food molecules by enzyme so they can be absorbed into the bloodstream
What are the part of the digestive system
Mouth: chews food. Containers saliva which has enzyme amylase
Gall bladder: stores excess bile
Oesophagus: connect to stomach. Food passes through it to go into stomach
Liver: makes bile which neutralises acid
Stomach: peristalsis: food churned- bigger surface area for enzymes
Pancreas: where enzymes are made
Small intestine: absorbs nutrients from food into blood through diffusion or active transport
Large intestine: water absorbed it blood
What is an enzyme
They are large protein molecules. They are biological catalysts that speed up the rate of a reaction
Where are protease made? What do they break down?
Made in small intestine, pancreas and stomach. Break down protein into amino acids
Where are amylase made? What do they break down
Made in small intestine, salivary glands and pancreas. Break down carbohydrates into simple sugars
Where are lipase made? Wat do they do
Made in small intestine and pancreas. They bread down fats into a glycerol and 3 fatty acids
What is bile
An alkaline substance made in the liver. Excess bile stored in gall bladder
What does bile do
Neutralise stomach acid and breaks down food into tiny droplets since it is alkaline. Emulsification of lipids- a big lipid molecule is turned into smaller lipid droplets do there is bigger surface area for lipase to break down lipids
What 2 factors effect enzyme activity?
Temperature, PH
How does temperature effect enzyme activity?
The more it increases, the more enzyme activity increases because the enzyme has more kinetic energy and moves faster which results in more collisions with substrate. After optimum temperature reached, enzyme denatures because active sight shape has changes so it no longer fits with the substrate. This results in the enzyme activities decreasing
How does PH effect enzyme activity
If to high or too low enzyme will denature. Enzymes interfere with bonds holding enzymes together
How is small intestine adapted for good digestion
. Good blood supply to maintain concentration gradient
. Capillaries increase surface area
. Moist
. Villi/ micro villi provide large surface area
. Very long small intestine increase time for absorption
. Cells have mitochondria so energy for active transport
What id a single circulatory system
Eg: in fish
. Blood pumped from heart to the gills where it collects oxygen and becomes oxygenated
. Oxygenated blood pass straight form gills to the organs where oxygen diffuses out of blood and into body cells
. Blood returns. The heart
What are problems with single circulatory system
Issue: blood looses lots of pressure when travelling through gills before it reaches organs so blood Tavel slowly so less oxygen is delivered
What is a double circulatory system
Blood travels to the heart twice. Right side of heart pumps deoxygenated blood to the heart. Left side pumps oxygenated blood t rest of the body
What s the benefit of a double circulatory system
Because blood pumped to heart twice, it can deliver oxygen rapidly to cells
The left ventral has a thicker muscle that the ride. Why?
So it can pump oxygenated blood at a higher pressure to the rest of the body
What i the purpose of the coronary artery?
To carry oxygenated blood to the heart muscle cells so the heart can have oxygen to Carry out respiration to have energy so it can pump blood around the body and beat properly
Where are the coronary arteries found?
Branch off the aorta around the heart