Reproduction: แบบฝึกหัด

Which of the following is an example of a natural method of asexual reproduction in plants?

In an investigation into the conditions required for seed germination, four test tubes are set up with the following conditions:
Tube 1: Moist cotton wool at \( 4^{\circ}\text{C} \) in the light.
Tube 2: Dry cotton wool at \( 25^{\circ}\text{C} \) in the light.
Tube 3: Moist cotton wool at \( 25^{\circ}\text{C} \) in the dark.
Tube 4: Boiled water covered with a layer of oil at \( 25^{\circ}\text{C} \).
In which tube will the seeds germinate most successfully?

In the human menstrual cycle, which of the following best describes the hormonal interaction that triggers ovulation and the subsequent maintenance of the uterine lining if fertilisation does not occur?

Which feature is an adaptation specifically found in insect-pollinated flowers to ensure successful pollination?

In the human menstrual cycle, how does oestrogen interact with the pituitary hormones FSH and LH?

Describe the function of the alkaline fluid secreted by the prostate gland during the formation of semen.

Explain the mechanism by which oestrogen levels during the follicular phase of the menstrual cycle influence the secretion of Follicle Stimulating Hormone (FSH) and Luteinising Hormone (LH), and state the specific event this triggers.

Explain how the amniotic fluid protects the developing fetus during pregnancy.

A student set up an experiment to investigate the conditions required for the germination of mung beans.
Tube A: Seeds, moist cotton wool, \( 20^{\circ}\text{C} \).
Tube B: Seeds, dry cotton wool, \( 20^{\circ}\text{C} \).
Tube C: Seeds, moist cotton wool, \( 4^{\circ}\text{C} \).
Tube D: Seeds, boiled water with an oil layer, \( 20^{\circ}\text{C} \).
a) Predict the results for each tube and explain the biological reason for the results in Tube D.
b) Identify the independent variable in this investigation.

Pollination is a critical step in the reproduction of flowering plants.
a) Contrast the structural adaptations of insect-pollinated and wind-pollinated flowers regarding their petals and pollen grains.
b) Explain how the growth of a pollen tube leads to the formation of a zygote.