B3 - Organisation and the digestive system Flashcards
All things are made up of…
basic building blocks called cells
similar cells sometime work together to…
form tissues
tissues have
specific functions
organs are made up of
different types of tissue grouped together to perform specific functions
organs work together in
organ systems to perform a particular function in the body
organ systems work together to
form whole organisms
different types of carbohydrates include
simple sugars and complex carbs
an example of a simple sugar is
glucose
an example of a complex carb is
starch
proteins are made up of
long chains of amino acids
lipids are made up of
fatty acids and glycerol
fats and oils are
lipids
Test for sugar and colour change
- Benedict’s solution
- orginally blue
- goes brick-red after heating if sugar is present
- (other colours are possible depending on amount of sugar - yellow, green, orange, brown)
test for starch and colour change
- iodine
- orginally orange-brown
- changes to blue-black if starch is present
test for protein and colour change
- biuret solution
- originally blue
- turns purple if protein is present
test for lipids and colour change
- ethanol (and cold water)
- orginally clear
- turns cloudy if lipid present
digestive system is an
organ system where several organs work together to absorb and digest food
main organs of the digestive system
- mouth
- oesophagus
- stomach
- liver
- gallbladder
- pancreas
- small intestine
- large intestine
function of the mouth
- Food is broken down into smaller pieces in the mouth by chewing.
- the amylase enzyme in the saliva starts to digest starch
function of the oesophagus
- moves ingested food into the stomach
- (by the muscles contracting)
function of the stomach
- churns the food
- produces hydrochloric acid (pH2)
- kills harmful microorganism
- enzymes in the stomach work best at pH 2
- protein digestion starts
function of the liver
- produces bile
- bile neutralises the acidic food mixture
- bile emulsifies fat
Epithelial tissue
A tissue that lines organs
Muscle tissue
A tissue that contracts to allow movement
Glandular tissue
A tissue that releases useful substance eg hormones and enzymes
Active site
Part of an enzyme where the substrate attaches
Substrate
The reactant that attaches to the enzyme
Denatured
When the active site of an enzyme has changed shape so the substrate is no longer able to attach
Metabolism
The sum of all reactions on a cell or body
Digestion
The process of breaking down large insoluble molecules into small soluble molecules
Enzyme
Biological catalyst made of protein that speeds up metabolic reactions
Emulsification
Large lipid droplets are made into smaller droplets which increase the surface area for lipase. The bigger the surface area the more expsoed substrate there is
Lock and key theory
Describing how a substrate and enzyme connect
Carbohydrate
A biological molecule that is used for energy
Lipids
A biological molecule that is an efficient energy store. Also important for making cell membranes and some hormones
