B2- Organisms [1] Flashcards
What do specialised cells do
Carry out a specific function
What is a tissue’s official definition
A group of cells that have a particular job
What is an enzyme
A biological catalyst
What happens when an enzyme has reach their optimum temperature
They increase the rate of reaction the fastest
What happens when an enzyme goes past its optimal temperature
It denatures
What does “denature” mean
It stops working
How does an enzyme “denaturing” work (lock and key theory)
Too much of an increased heat changes the shape of the active site and the substrate stops fitting
What two things effect the enzyme’s effectiveness
Ph and temperature
What coverts proteins into amino acids
Protease
What is proteins converted into by protease
Amino acids
What is starch converted into by amylase
Maltose
What is lipid converted into by lipids
Glycerol and fatty acids
What is bile produced
Liver
Where is bile stored before released
Gall bladder
What does the L.intestine do
Absorb excess water from the food
What does digestion begin
In the mouth with a salivary glands
What enzyme does the stomach produce
Protease
What does hydrochloric acid do
It kills bacteria and gives the right Ph for the enzymes to work
What is a rough stomach Ph
2 (acidic)
What does a “double circulatory system”
Two circuits joined together: the deoxygenated circuit and the oxygenated circuit
What do valves prevent
Backflow
Name all 4 heart chambers
Right and left atrium and right and left ventricle
What does a pacemaker do
Sends an electric pulse causing muscles to contract and make the heart beat regularly
What direction do arteries carry blood
Away from the heart
What direction do veins carry blood
To the heart
What is the hole in the arteries called
The lumen
What are some adaptions of arteries due to the bloods high pressure
Strong, thick and elastic walls
How thick are capillaries
One cell thick
What does a permeable wall mean
Substances can diffuse in and out of
What do capillaries join up and form
Veins
How to veins adapt for better blood flow
Bigger lumens
What is the shape of a red blood cell
Biconcave (donut shaped)
Why do red blood cells contain haemoglobin
Because it binds to oxygen
Why are red blood cells biconcave
Becuase the larger surface area allows more oxygen to be absorbed
TRUE OR FALSE: red blood cells contain nucleuses
False
What process is phagocytosis fae-go-si-toe-sis
Where a white blood cell engulfs a pathogen
Name two ways white blood cells get rid of unwanted microorganisms
Phagocytosis and producing antitoxins
