Organisation (biology) Flashcards
Cells are the
Building blocks of life
Tissues are
groups of similar cells working together to perform a specific function
Organs are
Group of different tissues that work together to perform a specific function
White blood cells….
Fight infections
Bigger than red blood cells
Platelets help…
Blood clot at the site of a wound
Protect new skin
Stops bacteria entering the wound
Stops you bleeding to death
Name 2 adaptations of the red blood cell
Bio concave- disc like shape, this means it maximises the surface area for oxygen to disuse across
No nucleus means the cell can carry more haemoglobin
Mechanical digestion is…
The digestion that:
Breaks food into smaller parts
Increases surface area of food , benefits the enzymes
Occurs in 2 ways CHEWING and PERISTALSIS (which is the walls of the stomach / small intestine contracting)
Chemical digestion includes:
Large insoluble molecules-> smaller soluble ones
Enzymes require to chemically change the food
An example of a carbohydrase is ……… . This breaks down starch a common carbohydrate.
Amalyse
When you breathe in the Diaphragm........ Ribs move..... Intercostal muscles ..... Pressure
The diaphragm contracts
The ribs move outwards
Inter coastal muscles contract
Pressure increases
How are the alveoli adapted?
- large surface area (diffusion occur quickly)
- only 1 cell thick (increases diffusion rate)
- surrounded by network of capillaries (allows gas to pass directly between lungs and bloodstream
- moist (gas molecules dissolve easily)
- large surface area (large amounts of gas exchanges with each breath)
Stomata are…
Small holes on the underside of leaves. Allow plants to take in carbon dioxide for photosynthesis.
Guard cells surround each stomata. They help regulate the rate of ………… They open and close the …….
Transpiration
Stomata
What does the waxy cuticle do?
Protects the leaf and reduces rate of water loss
The xylem carries…
Water Made of dead cells No cytoplasms Transports water and minerals Flow is upwards
Phloem …
Carries glucose
Made of living cells
Transports food
Flow is up and down
Benign tumour
Contained in a membrane, don’t spread
Malignant tumours
Cancer cells invade neighbouring tissues and spread to different parts of the body through the blood. These are called secondary tumours
What is nicotine
Powerful force acting on an addictive drug. Reaches brain and seven seconds increases heart rate and blood pressure
A carcinogen
Is a substance capable of causing cancer in living tissue
When you take in more energy than you need it is stored as
Fat
What are the risks of obesity
Arthritis, Type II diabetes, high blood pressure, strokes, heart disease, blocked arteries
What type of cancer can alcohol cause
Mouth and upper throat, breast, liver, bowel
How alcohol causes cancer…
If small amount of alcohol is drunk the body can process without doing much damage. If a large amount of alcohol is drunk the body can’t process it fast enough this causes a buildup of acetaldehyde. This is toxic and causes damage to DNA. Mistakes can cause mutations and mutations can cause cancer.
