Organisation Flashcards
(41 cards)
What is an organelle
A specialised unit within a cell which performs a specific function
What is a cell
Basic building blocks of all living organisms
What is tissue
A group of cells with similar structure and form
What is an organ
A group of tissue performing a specific function
What is an organ system
A group of organs with related functions, working together to perform certain functions within the body
What is the order of the digestive system
Mouth
Oesophagus
Stomach
Small intestine
Large intestine
Anus
What does the mouth do in the digestive system
Increases surface area of food
Saliva produces amylase which breaks starch (carbohydrase)
What does the oesophagus do in the digestive system
Contracts to push food down
What does the stomach do in the digestive system
Acid destroys microbes
Produces protease which breaks down protein
What does the small intestine do in the digestive system
Liver injects bile
Pancreas releases carbohydrase, protease, lipases
Villi absorb small nutrients into the blood
What does the big intestine do in the digestive system
Removes water from food that can’t be digested
What does the anus do in the digestive system
Faeces are pushed out here
What is bile
An alkaline which neutralises hydrochloric acid from the stomach
Produced in the liver
Stored in the gall bladder
Emulsifies fat to form small droplets to increase surface area which increases the rates of fat breakdown by lipases
What is an enzyme
A protein which catalyses a chemical reaction
A + B = C - anabolic (build up)
C = A + B - catabolic (break down)
What is the lock and key hypothesis
The enzyme has an active site (lock) which only one substrate (key) can fit in
When the substrate is in the active site, the activation energy is lowered to speed up the reaction
If the active site denatures, the substrate won’t be able to fit in it
What is amylase, where where it is produced and its equation
Type of carbohydrase which breaks down starch
Produced in the mouth
Amylase
Starch →Glucose
What is lipase, where it is produced and its equation
Breaks down lipids
Produced in the small intestine
Lipase
Lipid→Fatty acids + Glycerol
What is protease, where it is produced and its equation
Breaks down protein
Produced in the stomach
Protease
Protein →Amino acids
How do you do the test for sugar
Add benedict solution to the food
Heat it in a water bath
Benedict colour changes when heated
Red/brown - sugar present
Green/yellow - not much present
Orange - there’s a little bit
How do you do the test for starch
Put iodine on the starch
Blue-black - starch is present
How do you do the test for protein
Add the biuret solution A to the food solution
Mix the solution
Add biuret solution B to the side of the test tube
Purple - protein is present
A purple ring between layers - protein is present
How do you do the test for lipids
Ethanol is added to a test tube with the crushed food
The liquid is poured into a second test tube with water, leaving behind any food residue
Cloudy - lipids are present
What do the epidermal tissues do
Help deter excess water loss and invasion by insects and microorganisms
What does the palisade mesophyll do
Absorbs light, packed with many chloroplast and arranged closely
