Biology

A diagram of the different parts of a flower is shown.

Identify the structures where pollen and ovules are located.
Pollen ................................................
Ovules ...............................................

The graph below shows how the levels of three hormones change during pregnancy.
Identify hormone X

The graph below shows how the levels of three hormones change during pregnancy.
Outline ONE role of oestrogen during pregnancy.

The graph below shows how the levels of three hormones change during pregnancy.
How does the source of progesterone change as pregnancy progresses?

A diagram of the human female reproductive system is shown.
Where does implantation normally occur?
A. W
B. X
C. Y
D. Z

Offspring are rarely identical to their parents.
Compare the ways in which genetic variation can arise from asexual and sexual reproduction.

Which of the following photographs shows an example of sexual reproduction?

The hormones progesterone and luteinising hormone (LH) were measured in a woman’s blood over 40 days as shown below: When did her menstrual bleed start?
A. Day 8
B. Day 13
C. Day 21
D. Day 34

The graph shows the levels of three hormones, oestrogen, progesterone and human chorionic gonadotrophin (HCG), measured in the blood of a woman during her pregnancy.
Which statement can be inferred from the graph?
A. Birth occurred about week 36.
B. Fertilisation occurred at day 0.
C. Implantation occurred about week 4.
D. The placenta was formed about week 24.

Ovulation in women is associated with a rapid increase in luteinising hormone (LH). Test strips can be used to detect high levels of LH in urine. Once a test strip is used, a control line should appear and the presence of a test line indicates high levels of LH in urine. The image below represents four different results that were obtained.
Which of the results indicates a valid test which shows that ovulation is NOT occurring?
Justify your answer.

Sexual reproduction is a mechanism that has evolved to ensure the continuity of species. In animals several reproductive strategies ensure that reproduction occurs effectively in the environment they live in. Both internal and external fertilisation strategies are known to produce reproductive success.
“Internal fertilisation is more advantageous than external fertilisation in ensuring the continuity of a species”.
Assess the above statement.

In maintaining homeostasis, which of the following is a behavioural adaptation?
A. Sweating to cool down
B. Curling up in a ball to keep warm
C. Speeding up or slowing down cell metabolism
D. Skin going red as more blood flows to surface

Sexual reproduction in plants involves
A. pollination caused by dispersal of seeds.
B. cloning as it creates copies of the parent plant.
C. mitosis leading to the formation of pollen grains.
D. fertilisation as a result of fusion of male and female gametes.

The following four events occur during reproduction in a placental mammal. 1. Fertilisation 2. Implantation 3. Ovulation 4. Placental formation In which order do these events occur?
A. 2, 1, 3, 4
B. 2, 4, 1, 3
C. 3, 1, 2, 4
D. 3, 2, 4, 1

Explain ONE advantage for animals of using external fertilisation.

Students tested the hypothesis that the number of eggs/young produced was greater in animals using external fertilisation than those using internal fertilisation. They obtained the following data from secondary sources.
What conclusion can be drawn from the data? Justify your answer.

Which of the following is an advantage for animals using internal fertilisation rather than external fertilisation?
A. It prevents dehydration of gametes.
B. It involves large numbers of gametes.
C. It relies on adaptations such as mating rituals.
D. It allows gametes to combine to form unique offspring.

Yeast is a single-celled fungus that can reproduce by budding.
Outline a procedure that could be used to test the effect of temperature on reproduction in yeast.

Yeast is a single-celled fungus that can reproduce by budding.
What type of reproduction is budding?