B3- Organisation And The Digestive System Flashcards
What is a tissue
A group of cells with similar structure and function working together
What is an organ
Collection of tissues
What does each organ contain?
Several tissues, all working together to perform a specific function
What tissues do the stomach contain and what are their functions
muscular tissue- churn food + digestive juices of stomach together
glandular tissue-produces digestive juices that break down food
Epithelial tissue- covers the inside + outside of stomach
What two important functions do the pancreas has
Makes hormones to control blood sugars + enzymes that digest food
Contains two very dif. Types of tissue
What is an organ system
groups of organs that all work together to perform specific functions
What is the function of the liver?
Producing bile
Give me 4 examples of organ system
Circulatory
Digestive
Nervous
Excretory
What does carbohydrates break down into and by what enzyme?
Sugars
Carbohydrase
What are proteins broken down into and what enzyme?
Protease
Amino acids
What are fats broken into and what enzyme?
Lipase
Fatty acids and glycerol
What is ingestion?
Taking in of food w/ help of mouth
Happens w/ help of mouth
Teeth + tongue helps churning of food + mix of saliva
What is digestion
Breakdown of large insoluble particle into small soluble ones
Happens w/ help of stomach, intestine, pancreas and liver
What is absorption?
Digested food particles are absorbed into the blood
Small intestine
What is assimilation?
Using absorbed food for releasing energy and in body processes
In the body cells
Egestion
Getting rid of undigested food materials
By rectum and anus
What is Bile juice?
Green yellow ALKALINE liquid which is PRODUCED in the LIVER and STORED in the GALL BLADDER
What are two of bile juices major functions?
Neutralisation
Emulsification of fats
What is neutralisation in the body
food that comes out of stomach is acidic
enzymes of intestine can work in alkaline conditions
Bile neutralises food that come from stomach-makes it alkaline so enzyme released in the intestine can work effectively
What is the emulsifications of fat?
For lipase to work-> fat broken down into small droplets to increase surface area for the lipase to function
Bile performs this for efficient working lipase
What is the function of carbohydrates?
Principle source of energy
Fuel for respiration
Storage molecules
Structure molecules
What is an example of storage molecules
Starch and glycogen
What is an example of a structure molecule
Cellulose
What is the 3 functions for protein
Components of muscles
Required for growth and repair
Components of enzymes
Hormones like insulin
What are the 3 functions of fats
Insulates the body
Reserve source of energy
Components of cell membrane
What are all carbohydrates made up of?
Units of sugar
What elements do carbohydrates contain?
Carbon, hydrogen and oxygen
What is a simple sugar?
Small carbohydrate containing only one sugar unit
What is the best known single sugar?
What is the chemical formula
Glucose C6H12O6
What are complex carbohydrates? Give an example
Long chains of simple sugar units bonded together
Starch
Cellulose
What are lipids
Fats (solids) and oils (liquid)
Combined w other molecules, lipids are important where?
Cell membranes as hormones, and in nervous system
Truth or false: lipids are insoluble in water
True
What are lipids made up of?
Carbon, hydrogen and oxygen
What are lipids made up of?
three molecules of fatty acids joined to a molecule of glycerol
In lipids, glycerol is always the ______ but the fatty acids _______
same
Vary
What do lipid-rich food include?
all oil
butter, margarine, cheese, and cream
What does the different combination of fatty acids affect?
Whether the lipid will be a liquid oil or a solid fat
What are proteins used for?
building up the cells and tissues of the body
Basis of all enzymes
How much of your body mass is protein?
Between 15 and 16 percent
Where is protein found?
In tissues, ranging from your hair and nails to the muscles that move you around
In enzymes that control your body chemistry
What are proteins made up of?
Carbon hydrogen oxygen and nitrogen
Protein rich food include…
Meat fish pulses and cheese
What is a protein molecule made up of?
Long chains of small units called amino acids
There are __ different _____ _____, and they are _____ together into _____ _____ by ______ _____
i) 20
ii) amino acids
iii) joined
iv) long chains
v) special bonds
What shape are the long chains of amino acids that make up a protein
Folded, coiled, and twisted go make specific 3D shapes
What enables molecules to fit into a protein
The 3D specific shapes from the folded, coiled and twisted amino acids
The bonds that hold the proteins in these 3D shapes have what features?
v sensitive to temp and pH
Can be easily broken
What happens when the bonds that hold the proteins in these 3D shapes is broken?
Shape of protein is lost
May not function any more in your cells
What is the term that describes when the shape of protein is lost?
The protein is denatured
What 4 functions for proteins carry out?
Structural components of tissues (muscles and tendons)
Hormones (insulin)
Antibodies (destroy pathogens part of immune system)
Enzymes (catalyst)
In your body, what is the rate of chemical reactions controlled by?
Enzymes
What are enzymes?
Special biological catalysts that speed up reactions
What do enzymes do?
Each enzyme interacts w a particular substrate (reactant)
Enzymes are large _____ _________
Protein molecules
Why are the long chains of amino acids folded?
To produce a molecule with an active site that has a unique shape so it can bind to a specific substrate molecule
The ____ of an enzyme is vital for the enzyme to ______
i) shape
ii) function
What theory is a simple model of how enzyme works?
Lock and key theory
What does lock and key theory involve?
Substrate of reaction to be catalysed -fits into the active site of the enzyme
enzyme and the substrate bind together
What happens after the enzyme and substrate bind together?
Reaction takes place rapidly
The products are released from the surface of the enzyme.
What is another feature enzymes can do other than break up large molecules?
Enzymes can join small molecules together
TRUE OR FALSE Enzyms do change the reaction
False- they speed it up
What do enzymes control
Metabolism
Give me 3 ways in which different enzymes catalyse specific types of metabolic reactions
1) Building large molecules from lots of small ones
2) Changing one molecule into another
3) Breaking down large molecules into smaller ones
What does building large molecules from lots of smaller ones include?
Building starch, glycogen or cellulose from glucose
Lipids from fatty acids
Proteins from amino acids
Plant cells- combine co2 w h2o to make glucose- uses glucose + nitrate ions to make amino acids
What does changing one molecule into another include?
Changing one simple sugar into another
Such as glucose to fructose
And converting one amino acid into another
What does breaking down large molecules into smaller molecules include?
Breaking down carbs, lipids + proteins into their constituent molecules during digestion
Breaking down glucose in cellular respiration
Breaking down excess amino acids to form urea, and other molecules used in respiration
Do reactions that take place in the cell happen at relatively low or high temps?
Relatively low
What temperature are most organisms are able to withstand?
40 degrees celsius
What is affected after an organism reaches 40°C ?
Protein structure of the enzyme is affected by the high temp.
What happens to the long amino acid chains when an enzyme is said to be denatured?
Begin to unravel, and as a result, the shape of the active site changes. Substrate cannot fit active site and no longer acts as a catalyst
In which temp do most human enzymes work best?
37°C
Where does the shape if the active site if an enzyme come from?
Forces between dif. parts of the protein molecule
What do the forces between the different parts of the protein molecule do?
Holds the folded chains in place
What affects these forces between the different parts of the protein molecule?
A change in pH, changes shape of molecules
Most of your enzymes work where? Doing what?
Inside of cells; controlling the rate of chemical reactions
Where do the digestive enzymes work?
Outside of the cells
Where are enzymes produced?
By specialised cells in glands (pancreas) and in the lining of the digestive system
What happens to the enzymes after they are produced?
The enzymes pass put of these cells into the digestive system itself, where they come into contact w/ food molecules
What is your digestive system?
A hollow, MUSCULAR tube that squeezes your food that helps to break up your food into small pieces that have a large surface area for enzymes to work on
What enzyme catalyses the broken down of starch?
Amylase
Where is starch broken down to sugars?
Mouth
Small intestine
Where is amylase produced?
Salivary glands and pancreas
Where does the digestion of starch start?
In mouth
What catalyzes the break down of protein such as meat, fish and cheese into amino acids?
protease enzymes
Where is protease produced?
the stomach, pancreas and small intestine
Where does the breakdown of proteins into amino acids take place?
stomach and small intestine
Where is the lipase made?
pancreas and small intestine
What happens to the food molecules after theyhave been completely digested into soluble glucose, amino acids, fatty acids and glycerol?
They leave your small intenstine and then pass into the bloodstream to be carried around to body to the cells that need them
What do all the 35 millions glands in the lining of your stomach secrete?
Pepsin- protease enzyme- digests protein you eat
Which pH does pepsin work best at?
acidic
How much litres of hydochloric acid does your stomach produce a day?
30
why is it useful to have highly concentrated
hydrochloric acid in your stomach
Allows enzymes to work effectiviely
Kills most of the bacteria you take in w/ your food
The stomach produces a thick layer of mucus. What is it’s function?
coats stomach walls
protects them from being digested by the acid and enzymes
What happens if someone has a stomach ulcer?
Protecting mucus is lost
acid production may decrease
Lining of stomach is then attacked by the acid and protein-digesting enzymes- painful
