8. Transport in mammals
A section of Biology, 9700
Listing 10 of 589 questions
Blood samples were taken from a 29 year old woman each day for a period of 43 days. The concentrations of oestrogen, progesterone and luteinising hormone (LH) in each sample were measured. The results are shown in . time / days oestrogen progesterone LH oestrogen / pg cm – 3 progesterone / ng cm – 3 LH / mlU cm – 3 Estimate the length of the woman’s menstrual cycle. Show how you worked out your answer. answer The luteal phase is the part of the cycle when a corpus luteum is present in the ovaries. It begins immediately after ovulation, and ends when menstruation starts. Use to suggest when the luteal phase began and ended. began ………………………… ended ………………………… Name the organ that secretes LH. Describe the roles of LH in the menstrual cycle. An investigation was carried out to determine whether the ability of a woman to perform a task involving spatial ability varied at different times of her menstrual cycle. The investigation involved 12 women. They each performed 24 similar spatial tasks on day 2 and day 22 of their menstrual cycle, for six successive cycles. The tasks involved mentally rotating 3-D shapes. The researchers used two methods to determine the phase of the menstrual cycle. • Each woman was asked when her previous menstrual period had begun. • After each test, a blood sample was taken and the concentrations of oestrogen, progesterone and LH were measured. Suggest why the researchers used two methods to determine the phase of the menstrual cycle. The mean score for women taking the tests on day 2 of their cycle was 10.50 out of 24. The mean score for women taking the tests on day 22 of their cycle was 7.38 out of 24. Discuss whether or not these results support the hypothesis that the concentration of oestrogen in the blood affects the ability to perform spatial tasks.
9700_w13_qp_41
THEORY
2013
Paper 4, Variant 1
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Blood samples were taken from a 29 year old woman each day for a period of 43 days. The concentrations of oestrogen, progesterone and luteinising hormone (LH) in each sample were measured. The results are shown in . time / days oestrogen progesterone LH oestrogen / pg cm – 3 progesterone / ng cm – 3 LH / mlU cm – 3 Estimate the length of the woman’s menstrual cycle. Show how you worked out your answer. answer The luteal phase is the part of the cycle when a corpus luteum is present in the ovaries. It begins immediately after ovulation, and ends when menstruation starts. Use to suggest when the luteal phase began and ended. began ………………………… ended ………………………… Name the organ that secretes LH. Describe the roles of LH in the menstrual cycle. An investigation was carried out to determine whether the ability of a woman to perform a task involving spatial ability varied at different times of her menstrual cycle. The investigation involved 12 women. They each performed 24 similar spatial tasks on day 2 and day 22 of their menstrual cycle, for six successive cycles. The tasks involved mentally rotating 3-D shapes. The researchers used two methods to determine the phase of the menstrual cycle. • Each woman was asked when her previous menstrual period had begun. • After each test, a blood sample was taken and the concentrations of oestrogen, progesterone and LH were measured. Suggest why the researchers used two methods to determine the phase of the menstrual cycle. The mean score for women taking the tests on day 2 of their cycle was 10.50 out of 24. The mean score for women taking the tests on day 22 of their cycle was 7.38 out of 24. Discuss whether or not these results support the hypothesis that the concentration of oestrogen in the blood affects the ability to perform spatial tasks.
9700_w13_qp_42
THEORY
2013
Paper 4, Variant 2
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shows the concentration of two hormones, oestrogen and progesterone, in a woman’s blood during one menstrual cycle. A B C D E time / days progesterone oestrogen concentration of hormone in the blood / arbitrary units With reference to , state the letter of the stage of the cycle during which ovulation occurs. State how shows that the woman did not become pregnant during this cycle. Name the ovarian structure that secretes progesterone after ovulation. State the role of progesterone during stage D. The combined contraceptive pill contains oestrogen and progesterone. Explain how this combined contraceptive pill works to prevent pregnancy.
9700_w16_qp_43
THEORY
2016
Paper 4, Variant 3
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The statements list some of the events in the cardiac cycle. They are not in the correct order. The impulse travels through Purkyne tissue. A wave of excitation sweeps across the atria. The atrioventricular node delays the impulse for a fraction of a second. The sinoatrial node contracts. The wave of excitation sweeps upwards from the base of the ventricles. The ventricles contract. The atria contract. Which statement describes the sixth of these events to occur in the cardiac cycle?
9700_w21_qp_13
MCQ
2021
Paper 1, Variant 3
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Questions Discovered
589