B2 Organisation Flashcards
What is a cell?
Basic building block of living organisms.
What is a tissue?
A group of cells with similar structure and function?
What is an organ?
A group of different tissues performing specific functions.
What is an organ system?
A group of different organs working together. Makes up an organism.
What is an organelle?
Part of a cell - for example, nucleus.
Order the following: organ, tissue, organelle, organ system, cell (ascending order)
Organelle, cell, tissue, organ, organ system.
How many organ systems do humans have?
9
What are the 9 organ systems?
Digestive, respiratory, skeletal/muscular, excretory, immune, circulatory, endocrine (hormone), nervous, reproductive.
What is the purpose of the liver?
Produce bile to neutralise the pH of hydrochloric acid.
What is the purpose of the pancreas?
Release enzymes to break down food.
What is the purpose of the stomach?
Contains hydrochloric acid to break down food.
What is the purpose of the small intestine?
Absorbs water from the food.
What is the purpose of the large intestine?
Absorbs nutrients from food, before it exits the body as fishes.
What is a communicable disease?
A disease which is caused by pathogens and passed from person to person.
What is a non-communicable disease?
A disease which is not passed from person to person.
What factors could cause someone to develop a non-communicable disease?
Health, diet, stress, lifestyle, genetics
What are the 4 types of pathogens?
Viral, bacterial, fungal and protists
What are the similarities between bacteria and viruses?
Both pathogens, can rapidly reproduce outside the body.
How does bacteria reproduce?
Binary fission - divides by splitting.
How do viruses make you ill?
Live and reproduce inside body cells, damaging or destroying them.
How does bacteria make you ill?
Produces poisons and toxins in the body.
Name 2 examples of specialised cells:
Any 2 from: phloem cells, nerve cells, photosynthetic cells, muscle cells, sperm cells, xylem cells, root hair cells.
Where are embryonic stem cells found?
Inside the embryo.
Where are adult stem cells found?
In the human body after birth. BONE MARROW.
What is the equation for magnification?
Magnification = Image size / Actual size (I / AM)
How many millimetres in a centimetre?
10
How many micrometers in a millimetre?
1000
How many nanometres in a micrometer?
1000
What are the properties of a light microscope?
Lower resolution, cheaper, uses light and mirrors
What are the properties of an electron microscope?
Expensive, higher resolution, uses beams of light to make objects sea through
What are enzymes?
Proteins which are biological catalysts - they speed up reactions without being used up.
What are the 3 functions of different enzymes?
- Breaking down large molecules into smaller ones.
- Changing one molecule into another.
- Building large molecules from lots of smaller ones (ie. making proteins from amino acids).
What is the optimum pH?
The pH at which the rate of reaction is the highest - ie. enzymes are most effective.
What could cause an enzyme to become denatured?
More heat or a higher pH. Bad, as the substrate may no longer fit to react with the enzyme.
Explain lock and key theory.
An enzyme is formed with an empty space for a substrate. A substrate of the correct shape fits into this space and reacts with the enzyme to form products, which break off. If an enzyme becomes denatured, the substrate may no longer fit.
Where is amylase produced?
Salivary glands, pancreas, small intestine
Where is protease produced?
Stomach, pancreas, small intestine
Where is lipase produced?
Pancreas, small intestine
Where is bile produced?
Liver
What is the function of bile?
It is an alkali. It is sprayed onto acidic substances exiting the stomach via the gall bladder. This neutralises their pH as the small intestine/lipase needs an alkaline environment.
What is the function of amylase?
Breaks down starch into sugar.
What is the function of protease?
Breaks down proteins into amino acids.
What is the function of lipase?
Breaks down lipids into fatty acids and glycerol.
What is the function of muscle tissue in the stomach?
Churns the contents of the stomach.
What are the 2 types of respiration?
Aerobic and anaerobic.
What type of muscle makes up the heart?
Cardiac muscle.
What type of blood do veins carry?
Deoxygenated
What type of blood do arteries carry?
Oxygenated
Where do veins carry blood to and from?
Heart to lungs and back.
Where do arteries carry blood to and from?
Heart to rest of the body and back.
Where do coronary arteries supply blood to?
Oxygenated blood to the heart.
What is angina?
Heart pain caused by reduced blood supply.
Why is the muscle wall thicker on the left of the heart?
Thicker as blood must be pumped all around the body.
What do valves do in the heart?
Prevent back flow of blood.
What is coronary heart disease?
Heart disease caused by the build up of plaque in the coronary arteries.
Name 2 examples of heart treatments:
Stents, bypass surgery, statins, biological valves, mechanical valves, artificial pacemakers, heart transplants, artificial hearts.
Describe the properties of veins:
Wide lumen, valves, thinner muscle walls, carry deoxygenated blood.
Describe the properties of arteries:
Small lumen, thick muscle walls, carry oxygenated blood at high pressure.
Describe the properties of capillaries:
Walls one cell thick - shorter distance for diffusion, narrow - blood travels slowly, time for diffusion.
What are capillaries?
Small blood vessels which link arteries and veins.
How does gas exchange take place in the alveoli?
Diffusion - carbon dioxide passes out of blood and oxygen moves into blood.
How is the alveoli adapted for diffusion?
Moist lining, large surface area, efficient blood supply, thin wall - one cell thick.
Name 2 examples of communicable diseases:
Measles, smallpox, influenza, cardiovascular disease
Name 2 examples of non-communicable diseases:
Depression, asthma, cancer, athletes foot
Why does the stomach produce hydrochloric acid?
So that protease enzymes work effectively (optimum pH). Also kills most bacteria.
What is the function of bile?
Sprayed by the gall bladder to neutralise substances before they enter small intestine. Also emulsifies (breaks down) fats - gives them a larger surface area?
Define emulsification:
Breaks down - for example, when bile emulsifies fats to increase surface area.
Is bile an enzyme?
No. It does not break down fat molecules, it emulsifies fats into fat droplets.
