Metabolism

• What is meant by metabolism?

  The sum of all chemical reactions in a cell
• How does metabolism convert between different molecules?

  By facilitating chemical reactions in cells
• What is respiration in relation to metabolism?

  A chemical reaction that releases energy from glucose
• What is the role of enzymes in metabolism?

  To synthesize new molecules using released energy
• What are the key reactions in metabolism involving glucose?

  • Glucose is converted into cellulose in plant cells.
  • Glucose is converted into starch for storage in plant cells.
  • Glucose reacts with nitrate ions to form amino acids in plant cells.
  • Glucose is converted into glycogen in humans and animals.
• What is cellulose and its role in plant cells?

  A substance that strengthens the plant cell wall
• What is starch and its function in plant cells?

  A storage form of glucose in plants
• How do plant cells use glucose to make amino acids?

  By reacting glucose with nitrate ions
• What is glycogen and its role in humans and animals?

  A storage form of glucose in the body
• What is the process of lipid synthesis in metabolism?

  One glycerol molecule reacts with three fatty acids
• Where are lipids found in the body?

  In the cell membrane
• What happens to excess proteins in humans?

  They are broken down into urea
• How is urea excreted from the body?

  By the kidneys
• What are the main points about metabolism covered in the video?

  • Metabolism is the sum of all chemical reactions.
  • Glucose is central to metabolic reactions.
  • Key conversions include glucose to cellulose, starch, and amino acids in plants.
  • In animals, glucose is converted to glycogen.
  • Lipid synthesis involves glycerol and fatty acids.
  • Excess proteins are converted to urea for excretion.