Chapter B3: Organisation and Digestive system Flashcards
What is tissue?
Formed by lots of similar cells working together to perform the same function e.g. muscle tissue, blood tissue.
What is an organ?
Formed by lots of tissues working together e.g. heart lungs, brain.
What is an organ system?
Lots of organs working together in a system e.g. circulatory system, digestive system, nervous system.
What is the role of the small intestine?
To absorb nutrients and minerals from food.
What does bile do?
It helps digest food.
What is protein needed for?
They are needed for growth and repair of body tissues. They are made up of long chains of amino acids.
What are carbohydrates needed for?
They are needed to give us energy. There are 3 types of carbohydrates; starch, sugar and fibre. Starch and sugar gives us energy and fibre prevents constipation. They are made up of simple sugars e.g. glucose.
What are lipids needed for?
For energy and insulation. They’re made up of one molecule of glycerol and three attached fatty acids.
What are enzymes?
A biological catalyst that speeds up the rate of reactions in living things. They can only catalyse (break down) one substrate molecule because they have a specific shape called the active site.
What is a substrate molecule?
Where an enzyme acts. The substrate can bond with the enzyme active site and an enzyme substrate complex is formed.
What is the active site?
A place where an enzyme binds to a protein or other substance during a reaction.
What do protease enzymes do?
They break down proteins into amino acids.
What do lipase enzymes do?
They break down fats/lipids into fatty acids and glycerol.
What do carbohydrase enzymes do?
They break down carbohydrates into simple sugars.
What is a denatured enzyme?
When the enzyme’s active site starts to change shape when the temperature goes above 40 degrees.
What does plasma do in your body?
It transports dissolved substances around the body such as digested foods, gases, wastes and hormones. It also transports heat around the body.
What do red blood cells do in the body?
They carry oxygen around the body as oxyhemoglobin.
What do white blood cells do around the body?
They fight off diseases. For example, there are phagocytes which engulf/eat pathogens. And there are lymphocytes which create antibodies which kill pathogens.
What do platelets do in the body?
They help to clot blood and they make a scab.
What are arteries?
A tube where usually oxygenated blood is conveyed from the heart to all parts of the body.
What are veins?
Tubes that carry usually de-oxygenated blood towards the heart.
What are capillaries?
Tubes that link arteries and veins. They are only one cell thick.
What is a stent?
A metal or plastic tube inserted into the lumen of an anatomic vessel or duct to keep the passageway open.
What is a pacemaker?
A medical device which uses electrical impulses, delivered by electrodes contracting the heart muscles, to regulate the beating of the heart.
