human reproduction

• What is the average age when the menstrual cycle begins in females?

  Around 12
• The average length of the menstrual cycle is 28 days.
• On which day of the menstrual cycle does ovulation typically occur?

  Day 14
• Menstruation begins if the egg is fertilised during ovulation.

  False
• Why does menstruation occur during the menstrual cycle?

  Breakdown of uterine lining
• Menstruation typically lasts around 5-7 days.
• What happens to the uterine lining after menstruation ends?

  It thickens again
• Match the hormone with its primary role during the menstrual cycle:

  Oestrogen ↔️ Thickens uterine wall

  Progesterone ↔️ Maintains uterine lining
• When do oestrogen levels peak during the menstrual cycle?

  Just before day 14
• Progesterone levels stay high from day 1 to 14 of the menstrual cycle.

  False
• What causes the uterine lining to break down during menstruation?

  A fall in progesterone
• Arrange the phases of the menstrual cycle in the correct order:

  1️⃣ Menstruation

  2️⃣ Uterine lining thickens

  3️⃣ Ovulation

  4️⃣ Progesterone rises
• What are the four hormones involved in controlling the menstrual cycle?

  FSH, LH, oestrogen, progesterone
• FSH and LH are both released from the pituitary gland in the brain.
• What does FSH do to the egg in the ovary?

  Starts egg maturation
• FSH stimulates the ovaries to release oestrogen.
• LH is released when oestrogen levels have reached their peak.
• What are the two main effects of LH in the menstrual cycle?

  Ovulation and progesterone production
• Order the steps in the hormonal interaction during the menstrual cycle:

  1️⃣ Pituitary releases FSH to develop a follicle

  2️⃣ The follicle produces an egg and oestrogen

  3️⃣ Oestrogen stimulates uterine lining growth and inhibits FSH

  4️⃣ High oestrogen triggers LH release, causing ovulation

  5️⃣ The follicle becomes the corpus luteum, producing progesterone

  6️⃣ Progesterone maintains the uterine lining
• Oestrogen inhibits the release of FSH from the pituitary gland.
• Around which day of the menstrual cycle does ovulation typically occur?

  Day 14
• After ovulation, the follicle becomes the corpus luteum.
• If the egg is not fertilized, the corpus luteum breaks down and progesterone levels drop.
• What maintains progesterone production throughout pregnancy?

  The placenta
• What is the primary function of the penis?

  Introduces sperm into vagina
• The testes are the site of sperm formation
• The testes are suspended above the scrotum to keep them cool.
• What is the function of the prostate gland?

  Produces semen
• The Fallopian tubes are part of the female reproductive system
• The uterus lining grows to allow embryo development.
• What is the role of the blood supply in the uterus?

  Provides nutrients to fetus
• The cervix dilates to allow sperm to pass through to fertilize the egg
• The vagina is where sperm is deposited during sex.
• What happens during muscular contractions of the vagina during childbirth?

  Pushes baby out
• Match the sperm structure with its function:

  Head ↔️ Contains DNA

  Midpiece ↔️ Contains mitochondria

  Tail ↔️ Enables movement
• What is the role of sugars in semen?

  Provide energy for sperm
• Steps of fertilization in the Fallopian tube

  1️⃣ Sperm head releases enzymes

  2️⃣ Enzymes digest path through egg layer

  3️⃣ Sperm moves through egg membrane

  4️⃣ Egg releases material to prevent more sperm entry
• How many chromosomes does a haploid sperm or egg contain?

  23
• After fertilization, the zygote secretes a hormone called HCG
• Implantation occurs when the zygote attaches to the thickened uterus lining.