Organisation- biology

• What is a tissue?

  A group of cells with a similar structure and function
• What is an organ?

  A group of tissues working together for a specific function
• What are organs grouped into?

  Organ systems
• What happens during digestion?

  Large food molecules are broken down into small molecules by enzymes
• What in the stomach helps enzymes to digest protein?

  Hydrochloride acid
• Why is the digesting food turned into fluid?

  To increase the surface area for enzymes to digest
• How does bile help the digestion of lipids (Fats)?

  It speeds it up
• What organ releases bile?


  Liver
• What is a catalyst?


  Speeds up chemical reactions
• What is an enzyme?


  A large protein molecule
• What does the active site of an enzyme attach to?


  Substrate
• What is this?

  Enzyme.

  
• enzymes are specific. What does this mean? (Lock and key theory.)


  Th substrate must fit perfectly into the active site.
• What happens to the activity of the enzyme when the temperature is increased?

  The activity of the enzyme increases
• At a certain temperature enzymes work at their fastest rate. This is called the optimum temperature
• Enzyme has an optimum pH, where the activity is maximum
• If pH is too acidic or too alkaline then active site denatures
• How does the small intestines long length help with digestion?

  Provides a large surface area
• Villi in small intestine help increase surface area for digestion
• What does the vena cava do?

  Brings in deoxygenated blood from the body
• deoxygenated blood passes from the heart to the lungs through the pulmonary artery
• Blood collects oxygen from the lungs
• Oxygenated blood passes from the lungs to the heart in the pulmonary vein
• Oxygenated blood is pumped from the heart to the body in the aorta
• Vena cava to the pulmonary artery to the pulmonary vein to the aorta
• Why does the left side of the heart have a thicker muscular wall?

  Left ventricle pumps blood around the entire body while the right ventricle pumps blood to the lungs
• What do the coronary arteries do?

  Provide oxygen to the muscle cells of the heart
• What controls the resting heart rat?

  Pacemaker
• What does a artificial pacemaker do?

  Corrects irregularities in the heart rate