Transport in Living things Chapter 25.6 Transport system in man

What have we learnt so far… Transport system in Plants Structures? Xylem Functions? Transport water from roots to leaves Loss of water vapour from the aerial parts of the plant Consists of Transport manufactured food from leaves to other parts of the plant Translocation Transpiration Phloem Roots Absorbs water and mineral salts from the soil Osmosis? Diffusion? Active Transport? Where this process is called

Lesson objectives At the end of the lesson, you should be able to: - state the functions of blood red blood cells – haemoglobin and oxygen transport plasma – transport of blood cells, ions, soluble food substances, hormones, carbon dioxide, urea, vitamins, plasma proteins white blood cells – phagocytosis, antibody formation and tissue rejection

Why is there a need for a circulatory system? Simple diffusion cannot bring oxygen and food materials to cells deep within the body, and cannot remove waste products with sufficient speed Therefore, a transport system is needed. VS

3 main parts: Blood vessels tubes for blood to flow along Blood dissolves and carries materials Heart works as pump The mammalian circulatory system: Cardio- vascular system

Components of Blood source: nobelprize.org Plasma Blood cells Platelets White blood cells Red blood cells Blood

Four main components in blood Blood cells

What is Plasma?

Plasma a pale yellowish liquid, containing 90% water Substances such as proteins, food substances, excretory products (urea) are dissolved in it

Plasma Functions: -To transport digested food substances from the small intestines to other parts of the body - To transport carbon dioxide and waste products formed in cells to the excretory organs for removal - To transport other substances such as enzymes and hormones

Video clip Removal of waste products from blood

Components of Blood source: nobelprize.org Plasma Blood cells Platelets White blood cells Red blood cells Blood

Blood cells

Red and white blood cells from human blood

Red Blood Cells circular biconcave shape no nucleus diameter less than 0.01mm elastic (can squeeze through capillary) contain a red pigment called haemoglobin

Red Blood Cells Function of the red blood cells transports Oxygen from lungs to rest of body How is the structure of the red blood cell related to its function?

Red Blood Cells StructureFunction Circular, Biconcave Increase surface area of the cell: take in and release oxygen at a faster rate Contains haemoglobinTakes up oxygen from the lungs, releases it at the cells Elastic and can turn bell- shaped Enables it to squeeze through blood vessels smaller than itself in diameter

Red Blood Cells Video of red blood cells going through vessels

How the Red blood cells transport O 2

White Blood Cells colourless (no haemoglobin) larger than red blood cells ratio of red blood cells: white blood cells = about 700:1 irregular in shape has nucleus can move and change shape (able to squeeze through walls of capillaries) Video of WBC

White Blood Cells Function: Protection of body: fighting infections or diseases By either producing antibodies or digesting foreign particles such as bacteria White Blood cell

White blood cells 2 main kinds lymphocytesphagocytes produce antibodies that may protect the body from disease- causing organisms Ingest, take in and digest foreign particles such as bacteria

Phagocytes Phagocytes first engulf the bacteria by flowing over them and enclosing them It then ingests the bacteria Ingested bacteria will be digested by the phagocyte In the process of ‘fighting’ with the bacteria at the site of the wound, some phagocytes are killed These dead phagocytes with the dead bacteria, form pus. Video of white blood cell engulfing bacteria

Lymphocytes Production of antibodies -When disease- causing organisms or bacteria enter the bloodstream, lymphocytes produce certain chemical substances called antibodies.

White blood cellYEAST CELL Phagocytosis Phagocytosis is the process of engulfing and ingesting foreign particles, such as bacteria, by the white blood cells

White Blood Cells How is a soldier similar to a white blood cell?

White Blood Cells Protection of body: fighting infections or diseases By either producing antibodies or digesting foreign particles such as bacteria Make up body’s immune system: causing an immune response to foreign particles help keep body free from disease

Organ transplant or tissue rejection Organ or tissue transplant: replace a damaged or diseased tissue or organ with a healthy one from the same person or a donor WHY MUST THE DONOR HAVE A GENETIC SIMILARITY WITH THE RECIPIENT? WHAT WILL HAPPEN IF ORGAN IS NOT GENETICALLY SIMILAR?

Organ transplant or tissue rejection When transplanted, the organ must not be rejected by the recipient’s immune system An organ from another person’s body can trigger an immune response: the body treats it as a foreign object and lymphocytes produce antibodies to destroy it

Organ transplant or tissue rejection If the tissue to be transplanted comes from the same person, tissue rejection will not occur. To prevent tissue rejection, a)A tissue match is necessary: genetically alike (from family members) b) use immunosuppressant drugs which inhibit responses of recipient’s immune system

Organ transplant or tissue rejection In 2002, Ms De Cruz became the first person in Singapore to receive an organ transplant from an unrelated living donor. "Taking medication every day has become ordinary...The only thing I'm fearful about is becoming immune to the anti- rejection drugs I'm on and the possibility of renal failure."

Organ transplant or tissue rejection The use of immunosuppressant drugs can cause the recipient to have lower resistance to many kinds of infections The recipient has to continue to take these drugs for the rest of his/her life Video of Woman’s story about organ transplant

Clotting of blood Clotting seals wound, preventing excessive loss of blood Clotting prevents bacteria from entering the blood. Video of chain of events in clotting

Clotting of blood Fibrin threads entangle blood cells and the whole mass forms a clot Flash animation of clotting

Clotting of blood

Functions of blood 1.Transport function 2.Protective function

Function of blood 1.Transport function Digested food substances Excretory products (from tissues to excretory organs) e.g. nitrogenous waste products → kidneys carbon dioxide (bicarbonate ions) → lungs Hormones Heat O 2 (from lungs to rest of body) plasma Red Blood Cell

2.Protective function Guards against infection Blood clotting White Blood Cell platelets Function of blood

Protective function 1.Phagocytosis – process of engulfing & ingesting foreign particles e.g. bacteria by WBC 2.Antibody production (anti-toxins + agglutination) 3.Clotting/ coagulation of blood lymphocytes phagocytes

Summary Transport system in Man Heart Blood Blood vessels Capillaries Arteries Veins Red blood cells White blood cells Platelets Plasma Function: to pump blood to all parts of the body

Summary Blood Red blood cells White blood cells Platelets Plasma Function: For protection against infections and diseases Function: as a transport medium for food substances, excretory products Function: Transport oxygen from lungs to the rest of the body Function: Blood clotting to prevent excess blood loss

Summary White blood cells Lymphocytes Phagocytes Ingest and digest foreign particles like bacteria Produce antibodies that protect body from disease- causing organisms Types Properties Has nucleus Colourless Irregular shaped Larger and less than red blood cells Has nucleus Colourless Irregular shaped Larger and less than red blood cells

Additional slides 1.Haemophilia -A hereditary disease/ blood condition where the normal blood clotting mechanism is greatly impaired - slight injuries can cause the person to bleed to death or die of internal bleeding 2. Leukemia - Cancer of the blood and bone marrow

Additional slides 2. Leukemia - Broad term covering a spectrum of diseases -Cancer of the blood and bone marrow - characterized by an abnormal proliferation of blood cells (usually white blood cells)

Additional slides Acute leukemia: characterized by the rapid increase of immature blood cells. This crowding makes the bone marrow unable to produce healthy blood cells. Rapid progression and accumulation of the malignant cells spill over into the bloodstream and spread to other organs of the body.

Additional slides Chronic leukemia: distinguished by the excessive build up of relatively mature, but still abnormal, white blood cells. Typically taking months or years to progress, the cells are produced at a much higher rate than normal cells, resulting in many abnormal white blood cells in the blood.