Paper 2

• What is the function of leaves in plants?

  Photosynthesis and transpiration
• How does transpiration occur in plants?

  Water evaporates from leaves, creating a pull
• What are the xylem and phloem responsible for?

  Xylem transports water; phloem transports sugars
• What factors can increase the rate of transpiration?

  Higher temperature, lower humidity, increased air movement
• What is the function of the waterproof waxy cuticle on leaves?

  Prevents water loss through evaporation
• What is the role of chloroplasts in the palisade mesophyll layer?

  Site of photosynthesis in plant cells
• What is the function of stomata in leaves?

  Regulate gas exchange in and out of the leaf
• How do guard cells control the size of stomata?

  They change size to regulate gas exchange
• What type of reaction is photosynthesis?

  Endothermic reaction requiring light energy
• What can glucose produced in photosynthesis be used for?

  Respiration, starch, fat, cellulose, amino acids
• What factors can limit the rate of photosynthesis?

  Light intensity, temperatures, carbon dioxide concentration
• How can the rate of photosynthesis be measured practically?

  By measuring oxygen production from pondweed
• What is the role of the endocrine system?

  Secretes hormones affecting various body functions
• What is the function of the pituitary gland?

  Main gland producing hormones for other glands
• What hormone does the pancreas produce?

  Insulin to regulate blood glucose levels
• What happens when blood glucose levels are too high?

  Pancreas secretes insulin to lower levels
• What is type 1 diabetes?

  Condition where pancreas can't produce insulin
• What is type 2 diabetes?

  Condition where cells don't respond to insulin
• What hormones are involved in the menstrual cycle?

  FSH, estrogen, LH, progesterone
• What does FSH do in the menstrual cycle?

  Stimulates egg maturation in the ovary
• What is the role of estrogen in the menstrual cycle?

  Thickens the uterus lining and inhibits FSH
• What does LH do in the menstrual cycle?

  Triggers ovulation and egg release
• What is the function of progesterone in the menstrual cycle?

  Maintains the uterus lining for pregnancy
• What are some contraception methods?

  Pills, injections, condoms, IUDs
• What is IVF?

  Fertilization of eggs in a lab for pregnancy
• What is the structure of the heart?

  Center of the circulatory system with valves
• What is the double circulatory system?

  Blood enters the heart twice during circulation
• How does deoxygenated blood enter the heart?

  Through the vena cava into the right atrium
• What prevents backflow of blood in the heart?

  Valves between atria and ventricles
• Where does deoxygenated blood go after the right ventricle?

  To the lungs via the pulmonary artery
• Where does oxygenated blood return to the heart?

  Through the pulmonary vein into the left atrium
• What happens to developed embryos in IVF?

  They are inserted back into the uterus
• What is the success rate of embryo implantation in IVF?

  The success rate is very low
• What is a potential risk of multiple embryo implantation?

  More than one baby may be born
• What is at the center of the circulatory system?

  The heart
• What type of circulatory system do humans have?

  A double circulatory system
• How many times does blood enter the heart during circulation?

  Twice
• How does deoxygenated blood enter the heart?

  Through the vena cava
• What prevents backflow of blood in the heart?

  Valves
• How does oxygenated blood return to the heart?

  Through the pulmonary vein