organisation and the digestive system Flashcards
Tissues
A group of similar cells that work together to carry out a particular function
organs
A group of different tissues to work together to preform a particular function
In the digestive system what does the glands do?
produce digestive juices
In the digestive system what does the stomach and small intestine do?
digest food
In the digestive system what does the livver do
produces bile
what does the small intestine do?
absorbs soluble food molecules
what does the large intestine do?
absorbs water from undigested food leaving feces
Why is increasing the temperature for enzymes to work faster not advisable?
- Can damage cells
- Takes a lot of energy
- speeds up non- useful reactions
What is an catalyst?
A substance that increases the rate of reaction without being changed or used up in the process
What is an enzyme?
a biological catalysts that are made by living organisms
- large protein
active site
complementary to the substrate
lock and key model
Substrate had to fit perfectly into the active site
Induced fit model
Enzyme changes shape slightly as it binds to the substrate
What can effect the functioning of enzymes
- temperature
- pH
Temperature affects to rate of reaction
- At the start as the temp increases so does the
rate of reaction as all the particles will have
more kinetic energy, so more likely to collide
and enough energy to react. - After 37 degrees, the rate starts to drop rapidly
due to the enzyme becoming denatured
temperature affecting the function of enzyme
- High temperature starts to break the bonds
holding the enzyme together. - active site starts to change shape
- Active site then changes so much it can no
longer bind onto the substrate leaving it
denatured
pH affects on enzymes
- Some of the bonds holing the enzyme starts to break
- the active site will then start to change shape meaning it will slow the rate of reactions
Carbohydrates uses
- Energy source
e.g. chemical reactions and movement
Lipids/fat uses
- A long term energy source
- insulate
- protect organs
Protein uses
- Grow
- Repair tissues
- can be used for energy
biological molecules
Molecules found in living organisms and are produced by cells
Neutrients
Substances need for growth, repair and substances
What enzyme breaks down carbs?
Amylase
Where are amylase produced?
- salivary glands
- pancreas
- small intestine
What enzyme breaks down proteins?
Protease
Where are protease produced?
- stomach (pepsin)
- pancreas
- small intestine
What enzyme breaks down lipids
Lipases
Where can you find lipases?
- pancreas
- small intestine
where is bile produced, stored and released?
produced in liver then stored in gall bladder then released into small intestine
What makes the stomach pH too acidic for enzymes in small intestine to work properly?
Hydrochloric acid
Bile functions
- neutralizes acids
- emulsifies fats = break fat into tiny
droplets giving a bigger surface area of
fat for lipase to work on = digestion
faster
Role of salivary glands
saliva contains amylase and make food more liquidly to make it digest easily
Role of stomach
- contracts muscular walls to push food
around and mix it - produces pepsin (protease)
- produces hydrochloric acid kills
bacteria
Role of small intestine
- digested food absorbed into blood
stream
Role of pancreas
- produces lots of digestive enzymes in the form pancreatic juices to the small intestine
2 main roles of digestive system
- digest - break down large food
molecules into smaller ones - absorb - absorb these small molecule
into body
adaptation of villi
- increases surface area = food can be
absorbed into bloodstream quicker - single layer of surface cells = short
distance of diffusion - very good blood supply = maintains
concentration gradient
