organisation

• What do chemical reactions usually involve?

  Things being split apart or joined together
• Where is bile stored?

  Gall bladder
• Where is bile produced?

  Liver
• How do you calculate breathing rate?

  Breaths per minute = number of breaths divided by minutes
• What are the three types of blood vessels?

  Arteries, capillaries, and veins
• What do red blood cells carry?

  Oxygen from the lungs
• What shape do red blood cells have?

  Biconcave disc
• Why do red blood cells not have a nucleus?

  To carry more oxygen
• What pigment do red blood cells contain?

  Haemoglobin
• What happens to haemoglobin in the lungs?

  It binds to oxygen to become oxyhaemoglobin
• What happens to oxyhaemoglobin in body tissue?

  It splits to release oxygen into cells
• What is the circulatory system also called?

  Cardiovascular system
• What is the main function of the circulatory system?

  To transport substances around the body
• What organs make up the circulatory system?

  Heart, blood vessels, and blood
• What does blood carry in the circulatory system?

  Oxygen, nutrients, cells, and waste products
• Why do mammals have a double circulatory system?

  It contains two separate circuits for efficiency
• What are the two circuits in the double circulatory system?

  Pulmonary circuit and systemic circuit
• What happens in the pulmonary circuit?

  Blood flows from the heart to the lungs
• What happens in the systemic circuit?

  Blood flows from the heart to body tissues
• What are the four chambers of the heart?

  Right atrium, right ventricle, left atrium, left ventricle
• What are the atrioventricular valves' function?

  Ensure blood flows in one direction
• What is the body's largest vein?

  Vena cava
• What carries oxygenated blood from the lungs to the heart?

  Pulmonary vein
• What is the aorta's role in the circulatory system?

  It carries blood from the heart to the body
• What can happen if coronary arteries get blocked?

  It can lead to coronary artery disease
• What are the key components of the heart's structure?

  • Four chambers: right atrium, right ventricle, left atrium, left ventricle
  • Atrioventricular valves between atria and ventricles
  • Thicker muscular wall in the left ventricle
  • Coronary arteries supplying the heart muscle
• What are the functions of blood vessels in the circulatory system?

  • Carry blood throughout the body
  • Direct blood flow to various organs
  • Exchange gases and nutrients with tissues
• what is the role of pepsin?

  it is a protease enzyme which breaks down proteins into amino acids
• villi are found in the small intestine and they have a huge surface area, only have a single layer of surface cells and a good blood supply to support diffusion
• the villi help useful nutrients to diffuse from the small intestine into the bloodstream
• What is the procedure for preparing a food sample for testing?

  • Grind food sample with distilled water
  • Make a paste
  • Transfer to a beaker and add more distilled water
  • Stir to dissolve chemicals
  • Filter to remove suspended particles
• What are the two types of carbohydrates mentioned?

  Starch and sugars
• How do you test for starch in a food sample?

  Add iodine solution to the food solution
• What color change indicates the presence of starch when using iodine solution?

  Turns blue-black
• What color does iodine solution remain if no starch is present?

  Orange
• What is the procedure to test for sugars like glucose?

  Add Benedict solution and heat in water
• What does a green color indicate in the Benedict test?

  Small amount of sugar present
• What does a brick red color indicate in the Benedict test?

  Large amount of sugar present
• What type of sugars does the Benedict test work for?

  Reducing sugars
• What is the test for proteins?

  Add Biuret solution to the food solution