Biology - Module 5

HEART PROBLEMS
1. Hole in the heart
  1. Oxygenated and deoxygenated blood is allowed to mix as blood can move directly from one side of the heart to another through hole in the septum.
  2. The blood leaving the heart from the atria carries less oxygen. As a result, muscles receive less oxygen and therefore less energy.
  3. All unborn babies have this hole. They do not need a double circulatory system as their lungs do not function before they are born.
    1. When born, this hole closes. If this does not occur, the baby is born blue.
2. Damaged or weak valves
  1. Blood could flow backwards and with less pressure which means reduced pressure, leading to poor circulation.
  2. Artificial valves can be used as a replacement.
3. Blocked coronary artery
  1. If blocked, less blood flows to the heart and it can lead to a heart attack.
  2. By-pass surgery uses veins transplanted from other parts of the body. These take blood from the aorta, avoiding the blocked artery.
4. Heart assist devices
  1. Reduced work done by heart muscles.
  2. Often used for those people awaiting a heart transplant.
  3. Advantages: Improves quality of life, keeps patients alive, no problems with waiting for a donor or tissue match, no need for open heart surgery, no risk or rejection.
  4. Disadvantages: Valves and pacemakers might need replacing.
5. Artificial Pacemakers
  1. These are implanted under the skin and are a substitute for a natural pacemaker.
BLOOD GROUPS, CLOTTING & DONATION
1. Haemoglobin = The chemical you find in red blood cells, carries the oxygen.
2. Platelets = Fragments of cells that are involved in blood clotting.
3. White Blood Cells = They are involved with defending your body against disease
4. Red Blood Cells = Contain haemoglobin, carry oxygen around the body.
5. Plasma = 80% water, liquid part of the blood.
6. Blood Donor = Somebody who donates their blood.
7. Blood Transfusion = When you receive blood - The process in which the blood donor's blood is put into your body.
CLOTTING
1. Prevents entry by pathogens and stops you losing too much blood.
HAEMOPHILIA
1. An inherited disease in which blood fails to clot.
2. Queen Victoria suffered from Haemophilia.
PREVENTING BLOOD CLOTS
1. Anti-coagulant drugs e.g. warfin, heparin and asprin, can help to thin the blood and prevent clotting in vessels.
BLOOD CLOTTING = CASCADE PROCESS
1. Cut on the skin
  1. Platelets exposed to air.
    1. Several chemical reactions.
      1. Meshwork of fibrin forms.
        Clot forms
DONATING BLOOD
1. The blood donated by the donor must be compatible with the recipient for ma successful transfusion.
2. If it not compatible then agglutination (blood clumping) is caused. This is dangerous for the patient.
BLOOD GROUPS
1. Your blood group depends on the presence or absence of aggluinins.
  1. 2 proteins n the surface of RBCs (antigen A or B)
  2. 2 anti-bodies in blood plasma (serum) (anti-A or anti-B)
2. Donation of blood is based on the antigens on the surface of your RBCs.
3. Receipt of blood is based on the antibodies in your plasma.
RESPIRATORY SYSTEM
1. Inspiration = Forcing air into the lungs.
2. Expiration = Forcing air out of the lungs.
3. Breathing = The exchange of gases between the lungs and surrounding air.
4. Respiration = The breakdown of glucose to release energy.
BREATHING
1. Breathing In
  1. The intercostal muscles contract to lift the ribs up and outwards.
  2. The diaphragm contracts ad moves down.
  3. The volume inside the chest increases. Pressure is lower inside the thorax than out.
  4. This causes air to rush into your lungs and they inflate.
2. Breathing out
  1. The intercostal muscles relax to lower tbs down and inwards.
  2. The diaphragm relaxes and move up.
  3. The volume inside the chest decreases. Pressure is higher inside the thorax than out.
  4. This causes air to rush out of the lungs and they deflate.
ALVEOLI ADAPTATIOMS
1. Good blood supply - maintains concentration gradient
2. Large surface area - provided my many small alveoli.
3. Permeable lining - allows gases to pass across.
4. Moist surface - makes diffusion easier.
5. Thin lining (one cell thick) - provides diffusion pathway.

Next up

Biology - Module 5

Description

Resource summary

Similar

	Created by alice.finlay about 10 years ago