Reproduction (DP IB Biology: HL)

The following graph shows the hormones involved in the menstrual cycle.

Which line represents the hormone responsible for ovulation?

Polycystic ovary syndrome (PCOS) is a condition which may affect certain women during their childbearing years. Some of the most common symptoms of this condition is a failure to ovulate and irregular menstrual cycles. Women with PCOS have an increased risk of developing endometrial cancer.

What would be the most appropriate explanation for this?

The endometrium will:

The diagram shows the female reproductive system.

Which row correctly identifies the structures?

The following diagram shows the steps followed during in vitro fertilization.

Which row correctly identifies the steps?

The graph below shows a possible future consequence of climate change on plant flowering dates and the dates on which pollinators are active.

What would the consequence of the data shown in the graph be for plants and pollinators, and why?

Which of the following statements about pollen transfer are correct?

1. Self pollination occurs when pollen is transferred between separate flowers on the same plant.

2. Pollen transfer can be carried out by small mammals.

3. Pollen can be transferred when birds consume fleshy fruits and then carry out egestion in another location.

Which statement correctly describes the part labelled X in the image below?

The graph below shows the percentage of successful germination of seedlings in relation to the dispersal distance from the parent tree.

Which of the following explains the pattern shown in the data?

The image shows an animal pollinated flower

Identify the correct labels required for the image above.

The table below shows the effect of temperature on the germination of seeds. The seeds were first soaked in a range of temperatures before being germinated at either 20 °C or 35 °C.

Which of the following statements explains the results?

1. Higher temperatures slows down or stops germination

2. Enzymes are denatured when seeds are grown at higher temperatures

3. Seeds that were soaked at 20 °C germinated more successfully than seeds soaked at 35 °C

4. Soaking seeds at 35 °C had a less negative impact on germination compared to germinating at 35 °C

Which of the following statements about spermatogenesis are correct?

1. Spermatogenesis involves meiosis and mitosis.

2. Spermatogonia form from the germinal epithelium.

3. Primary spermatocytes form by differentiation from spermatids.

Some of the stages of oogenesis are listed below.

1. The oogonia enter meiosis I.

2. Ovulation releases the secondary oocyte from the ovary.

3. Cells in the germinal epithelium divide by mitosis.

4. FSH stimulates a primary follicle to mature and divide.

5. The secondary oocyte completes meiosis II.

Which of the following gives the correct process of oogenesis?

Which of the following does not form part of the fertilisation process in humans?

Which of the following gives a correct difference between a 48-hour-old embryo and a week-old blastocyst?

Which of the following statements about human chorionic gonadotropin (hCG) are correct?

1. hCG is released by the ovaries.

2. hCG stimulates the corpus luteum to continue secreting oestrogen and progesterone.

3. Once hCG secretion stops, oestrogen and progesterone secretion also stops.

Which of the hormone functions shown below are correct?

Which of the following statements can be correctly applied to the placenta?

Which of the following cell types are haploid?

Four hormones all interact to control the menstrual cycle via both negative and positive feedback.

Which of the below is an example of a negative feedback mechanism that occurs during the menstrual cycle?

Identify the set of images that correctly shows follicle development during the course of the menstrual cycle.

Scientists investigated the effect of temperature on the activity of pollinators. Feeders containing a sucrose solution representing nectar were kept at different temperatures. These feeders were exposed to pollinators and the number of visits each feeder received was recorded.

The results are shown in the graph below.

Which of the following is a correct statement based on the results above?

An investigation was carried out into the effect of pH on the germination of seeds of a species of plant. Scientists calculated the number of germinated seeds as a percentage of the total number of seeds planted at each soil pH value. To determine the germination rate the germination percentage for each pH value was divided by the number of days over which newly germinated seeds were observed during the investigation. Note that the error bars for germination rate show standard deviation.

The results of the investigation is shown in the graph below.

Which of the following provides the most accurate conclusion for this investigation.

The text below describes the first zone (i.e. the result window) of a pregnancy testing stick.

Identify the row in the table below that correctly completes the text above.

The image below shows a test strip used for drugs testing. Unlike the hormone in a pregnancy test, the substances tested for in this kind of drugs test are too small to bind to more than one antibody at the same time. This type of test is known as a competitive binding assay.

The components of the test contain the following:

Conjugate pad - antibodies complementary to the drug being tested for. The antibodies are attached to a coloured bead.

Test line - bound molecules of the drug being tested for.

Control line - bound antibodies complementary to the antibody from the conjugate pad.

Which of the following correctly explains the appearance of a positive result?

The zona pellucida in mice contains three different types of glycoprotein, known as ZP1, ZP2, and ZP3. The roles of each glycoprotein type are thought to be as follows:

ZP1 - provides structural support to the zona pellucida.

ZP2 - a secondary binding protein to which sperm cells bind after the initial stages of fertilisation are complete. The enzymes contained in cortical granules are thought to break down ZP2.

ZP3 - a primary binding protein to which sperm bind at the beginning of the fertilisation process.

Which row correctly explains the mutation that is most likely to result in polyspermy?

The diagram below shows some of the organs and hormones involved in childbirth.

Which row in the table gives the correct labels for locations 1-4 in the diagram?