Biology P1 - Organisation Flashcards
Label this diagram
Why is digestion necessary?
Because it breaks down food for usage by the body
Explain how physical digestion is different to chemical digestion
Physical digestion is the breaking down of food into smaller pieces, whereas chemical digestion is the breakdown of food by enzymes into smaller molecules for absorption by the blood
What enzyme reacts starch to glucose
Amylase
In most organisms cells are arranged into what?
Tissues
Glandular tissue produces what?
Substances such as enzymes and hormones
What are organs?
Groups of different tissues, which all work together to perform a specific job
List some types of tissues in the stomach
-Muscle tissue that contracts to churn the contents
-Glandular tissue to produce digestive juices
-Epithelial tissue to cover the outside and inside of the stomach
What are organ systems?
Organs organised into groups working together to do a particular job
What are enzymes?
Biological catalysts - they speed up chemical reactions in living organisms
What is denaturing
When high temperatures and extremes of pH make enzymes change shapes
What is the ‘lock and key theory’?
A model used to explain how enzymes work: the chemical that reacts is called the substrate (key) and it fits into the enzyme’s active site (lock)
What is Amylase?
-Produced in the salivary glands and the pancreas
-Is a carbohydrase that breaks down starch into sugar (maltose)
What is Protease?
-Is produced in the stomach, pancreas and the small intestine
-Breaks down proteins into amino acids
What is Lipase?
-Is produced in the pancreas and small intestine
-Breaks down lipids (fats) into fatty acids and glycerol
What is Bile?
-A liquid made in the liver and stored in the gall bladder.
-It is alkaline to neutralise hydrochloric acid from the stomach
-Emulsifies fat to form small droplets, increasing the surface area for enzymes to act on.
-The alkaline conditions and large surface area increase the rate at which fat is broken down by lipase
What type of molecule is an enzyme?
A protein
Give two factors that affect how enzymes work
Temperature and pH
Where are protease enzymes produced in the body
Stomach, pancreas and small intestine
What type of enzyme breaks down lipids
Lipase
Where is Bile produced?
The liver
What is blood made of?
A liquid called plasma which has three different components suspended in it:
-red blood cells
-white blood cells
-platelets
Red blood cells contain:
Haemoglobin, which binds to oxygen to transport it from the lungs to the tissues and cells, which need it for respiration
What are platelets?
Fragments of cells, which collect at wounds and trigger blood clotting
What do arteries do?
Take blood from your heart to your organs
What do veins do?
take blood from your organs to your heart
What do capillaries do?
Allow substances produced and needed by cells to pass in and out of the blood.
The heart pumps blood around the body in a:
Double circulatory system.
There are four chambers in the heart:
-the left and right —–, which receive blood from the veins
-the left and right ———-, which pump the blood out of the arteries
Atria
Ventricles
The natural resting heart rate is controlled by a group of cells located in the right atrium, which act as a ——
Pacemaker
The heart sends blood to the lungs via the
pulmonary artery
Air obtained by breathing reaches the lungs through the ——-, (windpipe), which has rings of ———– to prevent it collapsing
Trachea
Cartilage
Which component of blood makes it clot?
Platelets
How are red blood cells adapted to carry oxygen?
-They don’t have a nucleus to allow for more room for haemoglobin
-They are very small, so they can fit through the tiny capillary
-Are shaped like biconcave discs, giving them a large surface area that oxygen can quickly diffuse across
Which type of blood vessel carries blood away from the heart
Artery
In which chamber does deoxygenated blood enter the heart
Right atrium
What do the heart and veins contain to prevent backflow of blood
Valves
What controls the resting heart rate?
A group of cells which act as a pacemaker
Label this diagram
Describe Veins
-Take blood from your organs to your heart
-Thinner walls and valves to prevent backflow
Describe Arteries
-Take blood from your heart to your organs
-Thick walls made from muscle and elastic fibres
Describe Capillaries
-Allow substances needed by the cells to pass out of the blood
-Allow substances produced by the cells to pass into the blood
-Narrow, thin-walled blood vessels
