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Biology

GCSE · Edexcel

QuestionsFlashcards

Photosynthesis
Plant Structure
Transport in Plants
Plant Hormones
- Plant Hormones & Growth
  7
- Using Plant Hormones Commercially
  7

Transport in Animals
- The Need for Transport
  7
- Factors Affecting the Rate of Diffusion
  7
Respiration
- Respiration
  6
- Practical: Investigating Respiration
  5
Gas Exchange
Circulatory System
- The Blood & Blood Vessels
  6
- The Circulatory System
  8

Hormones & the Menstrual Cycle Flashcards

All 7 cards in this deck

What is the role of FSH in the menstrual cycle?: Released by the pituitary; it makes an egg mature in a follicle in the ovary and stimulates the ovaries to produce oestrogen.
What does a surge of LH cause in the menstrual cycle?: Ovulation — the release of the mature egg from the ovary, around day 14.
What is the role of oestrogen in the menstrual cycle?: It makes the lining of the uterus repair and thicken; at high levels it inhibits FSH and stimulates the release of LH.
Which structure produces progesterone, and what does it do?: The corpus luteum in the ovary; progesterone maintains the thickened uterus lining and inhibits FSH and LH.
What causes menstruation at the end of the menstrual cycle?: Progesterone and oestrogen levels fall, so the uterus lining breaks down and is lost (days 1–5).
What effect do the low oestrogen levels of women over about 50 have on ovulation?: Oestrogen levels are too low for LH to be released, and a surge of LH is needed for ovulation, so ovulation is unlikely.
True or false? Menstruation is the release of an egg cell from the ovary.: False. Menstruation is the breakdown and loss of the uterus lining; the release of an egg cell is ovulation, around day 14.