human body 2

Question 1

draw and annotate female reproductive system

Question 2

draw and annotate male reproductive system

Question 3

how does a pregnancy test work

Question 4

explain muscle contracting

Answer 4

• a chemical called ACh is released at the muscle
  it starts an electric signal in the muscle cell
• the signal makes the muscle release calcium ions inside the cell
• calcium moves tropomyosin (protein) out of the way so myosin can attach to actin
• myosin heads attach to actin
• myosins pull actin, shortening the muscle (the contraction)
• ATP makes myosin let go and reset to attach again
• as long as calcium and ATP are present cycle repeats and muscle stays contracted

Question 5

hormones during period

Answer 5

• estrogen and progesterone levels are low, causing uterus lining to shed
• FSH begins to rise and develops follicles in ovary
• growing follicles release estrogen which helps rebuilt uterus lining
• spike in LH during ovulation which triggers release of the egg from mature follicle
• empty follicle becomes corpus luteus, which releases progesterone and estrogen