ER 2

• what blood is made of


  plasma, red blood cells (erythrocytes), white blood cells (leucocytes), platelets(thrombocytes)
• functions of the blood


  transport

  distribution of heat

  defense against disease

  controlling blood loss

  pH regulation

  water reservoir
• fob - transport


  gases, cells, hormones, nutrients, clotting proteins
• fob - distribution of heat 


  distributes body heat
• fob - defense against disease


  phagocytic leucocytes, antibodies
• fob - controlling blood loss


  thrombocytes, clotting factors
• fob - pH regulation


  controls pH of body tissues (bicarbonate and carbonic acid)
• fob - water reservoir


  reserves of water that ensures osmotic balance to cells
• what blood is


  liquid connective tissue

  consists of cells (red and white) and liquid plasma

  5L av. in adults

  8% of body mass

  pH 7.35-7.45 (close to neutral)
• blood composition - plasma


  makes up 55% of the blood

  90% of plasma is water

  10% of plasma is dissolved cells
• blood composition - cells


  cells make up 45% of the blood
• plasma composition


  proteins - hormones, enzymes, antibodies

  ion - e.g. sodium, chloride, potassium, calcium, iron

  respiratory gases - carbon dioxide and oxygen

  nutrients - glucose, amino acids, fatty acids, cholestrol

  dissolved wastes - urea
• erythrocytes


  functions to carry oxygen in the haemoglobin molecule

  no nucleus

  biconcave disc - increases SA

  life span - 80-120 days

  removed by spleen and liver

  43-58 M per cubic mm

  formed in bone marrow
• leucocytes


  functions in the defence of the body to infection

  have a nucleus

  phagocytic action

  life span - a few days

  different varieties - monocytes, lymphocytes etc.

  5-10K per cubic mm

  formed in bone marrow
• thrombocytes


  functions to stick to the fibrous network that forms during the blood clotting process

  cell fragments

  no nucleus

  life span - 7 days

  formed in bone marrow
• carbohydrate (3)


  structure - C, H, O ; starch, sucrose and lactose (polysaccharides)

  single unit - glucose (monosaccharide)

  function in the body - immediate energy source

  dietary sources - potatoes, wheat, rice, fruit, vegetables

  deficiency - hypoglycemia
• lipids (3)


  structure - C, H, O ; triglycerides, lipids

  single unit - glycerol and fatty acids

  function in the body - long term energy storage

  dietary sources - nuts, avocadoes, meat, milk

  deficiency - hypolipidemia
• proteins (3)


  structure - C, H, O, N ; protein

  single unit - amino acids

  function in the body - growth, repair, making enzymes

  dietary sources - meat, eggs, soya beans, lentils

  deficiency - kwashiorkor (protein deficiency)
• carbohydrates (4)


  mouth saliva ~ starch (polysaccharide) - salivary amylase -> maltose

  stomach ~ no reaction

  duodenum/pancreas ~ starch (polysaccharide) - pancreatic amylase -> maltose (particles that did not reaction in the mouth)

  small intestine/intestinal glands ~ maltose - intestinal amylase (maltase, sucrase, lactase) -> glucose (monosaccharide)

  absorption ~ glucose into villi capillaries by facilitated diffusion

  destination ~ hepatic portal vein to the liver
• proteins (4)


  mouth saliva ~ no reaction

  stomach ~ proteins (large polypeptides) - gastric protease (pepsin) -> smaller polypeptides

  duodenum/pancreas ~ smaller polypeptides - pancreatic protease -> peptides

  small intestine/intestinal glands ~ peptides - intestinal protease -> amino acids

  absorption ~ amino acids into villi capillaries by facilitated diffusion

  destination ~ hepatic portal vein to the liver
• lipids (4)


  mouth saliva ~ no reaction

  stomach ~ no reaction

  duodenum/pancreas ~ liver releases bile that emulsifies fats (mechanical digestion), lipids - pancreatic lipase -> glycerol and fatty acids

  small intestine/intestinal glands ~ lipids - intestinal lipase -> glycerol and fatty acids (particles that did not react in duodenum)

  absorption ~ glycerol and fatty acids into lacteals by active transport

  destination ~ lymphatic system which joins the general blood circulation via the subclavian vein
• active site / lock and key model

  catabolic example:

  A) two

  B) active site

  C) enzyme-substrate complex

  D) enzyme

  E) substrate

  F) key

  G) lock