B7 – Further Biology
· Respiration isn’t breathing in and out.
o It’s the process of releasing energy from glucose, which happens constantly in every cell.
· Aerobic respiration needs plenty of oxygen.
o Glucose + Oxygen → Carbon Dioxide + Water (+ energy released)
· Energy released from respiration is used to make ATP.
o It’s broken down to ADP when energy is released.
o ATP is synthesised from ADP using energy from respiration.
· You respire more when you exercise.
o More ATP is used to contract you’re muscles so you need more energy, so respiration increases.
o Breathing rate increased to get more oxygen into the blood.
o Heart rate increases to get glucose and oxygenated blood around the body to your muscle quicker, and remove CO₂ quickly at the same time.
· Anaerobic respiration doesn’t use oxygen at all.
o Sometimes you can’t supply your body with all the oxygen that it needs.
o So in anaerobic respiration glucose → lactic acid (+ energy released) and you produce energy but lactic acid builds up in your muscles.
o You need oxygen to clear up this acid, so you are in an oxygen debt.
o So you keep breathing for a while after you stop exercise.
Blood and blood typing
· Blood is a fluid made of cells, platelets and plasma.
o Red blood cells – Transports oxygen from lungs to all the cells in the body.
o Plasma – Liquid that carries everything.
o White blood cells – Fight infection from microorganisms.
o Platelets – Small cell fragments that help the blood to clot.
· Blood type is important in transfusions.
o If you have the wrong blood in you it can trigger the immune system to attack it and it will make the blood clot.
o Blood type A has A antigens and B anti bodies, so B has B antigens and A antibodies.
o AB has no antibodies so can take all blood but because of its 2 antigens it can’t give blood.
o O is opposite to AB as it has no antigens but both antibodies.
Inheritance of Blood types
· Alleles are different versions of the same gene.
o ABO blood type is determined by a single gene that has 3 alleles.
o Io is for blood type O. Ia for A, and Ib for B.
o Io is recessive but Ia and Ib are co-dominant.
The Circulatory System
Humans have a double circulatory system.
o One pumps deoxygenated blood to the lungs and back to the heart.
o One pumps oxygenated blood around and back to the heart.
· Chemicals are being exchanged between cells and capillaries.
o Arteries branch into capillaries which are tiny blood vessels.
o Small molecules…