Biology GCSE OCR Gateway B5 Revision Cards

• Exoskeleton e.g. Snails
• Endoskeleton e.g. humans
• Cartilage- bone has cartilage at the top, this goes under ossification to harden and grow.
• They can be damaged if fractured or knocked or if you get a disease such as osteoporosis.  

• Ligaments hold bone together.
• Cartilage stops them rubbing together.
• Synovial fluid is used to lubricate bones and joints.
• Biceps and triceps move the arm.
• Biceps relax and triceps contract = straight.
• Biceps contract and triceps relax = bent.
• You can replace with artificial joints e.g. hip and knee so people can walk

Disadvantages of joint replacements:-

• Can be painful and inflamed, get dislocated and infected.
• Could end up with different leg lengths
• Must be re-replaced every 12-15 years. 

• Hole In the heart- oxygenated blood leaks onto the other side.
• Damaged Valves- High blood pressure.
• Coronary heart disease- Heart attack.

You can get: Transplants, pacemakers or a heart assisted device.

Causes include: Saturated fats (bad diets), alcohol, smoking, stress and drugs. 

We have a double circulatory system. Blood goes through the heart twice on one circuit of the body. There are for chambers in our heart. Fish have a single circulatory system with a two chambered heart. 

Arteries= high pressure    Veins = low pressure

• Platelets gather and 'plug' the area held together by protein and clotting factor.
• Vitamin K helps blot clots
• Alcohol and Cranberries slow blood clots
• To little clotting = bruise easily and risk of bleeding to death.
• To much clotting= DVT and stroke risks.

Blood Group       Antigens     Antibodies          Give to            Get from                  

     A                      A           anti-B                  A & AB                 A & O                

     B                     AB           anti-A                 B & AB                 B&O                  

   AB                    AB            none                    AB                      any                  

     O                  none         anti- A &B             Any                     O                       

You need to be the right rhesus (positive or negative) to give to a donor- you must match.

• Pulse rate increases with adrenaline is released getting more Oxygen to the body.
• Pacemaker Cell:- SAN sends message to the AVN and makes Atria contract. AVN sends message to make ventricle contract. ECG's (echo cardiogram) measure this. They can indicate heart failure, decreased  pumping ability, heart murmurs and torn valves. 

• You can be both a living or dead donor.
• You can donate one thing or many.
• There's a shortage of donors.
• It's major surgery so there are risks attached e.g. rejection so you will have to take immunosuppressant drugs.
• Ethical issues- body should be intact when you die, life and death are chosen by God, might not work, pressure to be a living donor.
• Mechanical replacements- Kidney dialysis, heart and lung machine. (temporary, risk of infection).

• Breathing takes muscles- Diaphragm and Intercostal. 
• Total Volume in lungs= Total air capacity.
• Normal Breaths= Tidal volume.
• Air Left= Residual air.
• Total capacity - Residual air = Vital capacity (Usable air)

Cilia and Mucas:- Protect lungs by catching dust as they're prone to infection, cilia brushes it back.

Alveoli Adaptations:- Large surface area, moist surface area,  thin lining, good blood supply.

• Frogs Respiration:- Air moves in and out through the skin and lung meaning that they loose moisture very quickly.
• Fish Respiration:- Gills used, which have a large surface area, which are supported by the water by water due to lots of folds.

Lung Diseases- causes:

• Industrial material e.g. asbestos
• Genetic causes e.g. Cystic Fibrosis
• Life style causes e.g. Smoking
• Asthma

• Replace urea.
• Adjusts blood iron levels .
• Adjusts blood water levels.
• Under High pressure.

Nephrons:-Ultrafilter; membrane, Reabsorb sugars and release water; ions and water.

Water:-Controlled by hormone ADH hormone for purity gland by negative feedback.

Urine depends on:- Heat- Sweat, Exercise and Water intake.

• Filters blood mechanically for people who have kidney failure.
• Regularly done to keep glucose and salt levels at the right concentration and remove waste.
• The dialysis fluid has the same concentration of salt and glucose as blood plasma.
• Permeable barrier so waste goes into dialysis fluid and not proteins.