IB Biology SL D3.1 Reproduction Questions

Practise IB Biology SL D3.1 by comparing reproduction, identifying anatomy and tracing hormones, fertilization and reproductive technology.

41 questions in this syllabus scope, with question parts counted together.

Syllabus
First assessment 2025
Course
Biology SL
Level
SL

Exam analysis

SL · 2010–2025
Papers with this topic35 / 141in the analysed sample
Latest appearanceNovember 2025
Tagged question parts44
Paper types5

Most tested objectives

  1. D3.1.5—Ovarian and uterine cycles18 papers
  2. D3.1.4—Human reproductive system anatomy11 papers
  3. D3.1.1—Sexual vs. asexual reproduction6 papers
  4. D3.1.7—In vitro fertilization (IVF)2 papers
  5. D3.1.8—Sexual reproduction in flowering plants2 papers

Common question formats

  • Definition or recall
  • Diagram interpretation
  • Process explanation
  • Comparison
  • Evaluation
  • Experimental design
  • Graph interpretation

Recent exam appearances

November 2025Paper 1A SL · TZ1Q19[ 1 ]
May 2025Paper 2 SL · TZ3Q8(a)[ 4 ]
May 2025Paper 1B SL · TZ2Q4(c), 4(d)(i), 4(d)(ii)[ 5 ]

141 papers analysed · Tagging incomplete

Exam points

  • Explain how asexual reproduction produces mitotic clones with little genetic variation.
  • Identify male and female reproductive structures and explain their functions.
  • Interpret ovarian and uterine cycle graphs using FSH, LH, oestrogen and progesterone feedback.
  • Explain human fertilisation as sperm entry and fusion of gamete nuclei into a diploid zygote.
  • Sequence IVF from hormone treatment and egg collection to embryo culture and transfer.
  • Label flower structures, distinguish pollination from fertilisation, and locate meiosis and gamete formation.
  • Explain how dioecy, asynchronous flower maturation and self-incompatibility reduce self-pollination and inbreeding.

Covered syllabus points

D3.1.1—Sexual vs. asexual reproductionD3.1.2—Role of meiosis and gamete fusionD3.1.3—Male vs. female sexesD3.1.4—Human reproductive system anatomyD3.1.5—Ovarian and uterine cyclesD3.1.6—Fertilization in humansD3.1.7—In vitro fertilization (IVF)D3.1.8—Sexual reproduction in flowering plantsD3.1.9—Insect-pollinated flower featuresD3.1.10—Promoting cross-pollinationD3.1.11—Self-incompatibility mechanismsD3.1.12—Seed dispersal and germination

Exam points

  • Define a clone as genetically identical cells or organisms derived from one parent.
  • Outline natural cloning in plants, Hydra and fungi through vegetative propagation or budding.
  • Predict similar genomes in vegetatively propagated offspring, allowing for differences caused by mutation.
  • Explain why cloned plant species may adapt slowly when their offspring are genetically alike.

Question 1

[Maximum number: 1]

Some plant species reproduce by cloning instead of sexual reproduction. Are these species likely to adapt rapidly or slowly to environmental change, and what is a reason for this?

A

Rapidly, as mutation rates are high during cloning

B

Rapidly, as combinations of genes are reassorted by meiosis

C

Slowly, as offspring produced by cloning are genetically identical

D

Slowly, as fewer offspring are produced than with sexual reproduction

Exam points

  • Identify meiosis and fertilization as sources of genetic variation, not natural selection.

Question 1

[Maximum number: 1]

Which of the following will promote variation in a species?

I. Meiosis
II. Fertilization
III. Natural selection

A

I only

B

II only

C

I and II only

D

I, II and III

No public sample questions are available for this syllabus point yet.

Exam points

  • Draw and label the male system: testes, epididymis, sperm duct, glands, urethra and penis.
  • Draw and label female anatomy: ovaries, oviducts, uterus, endometrium, cervix, vagina and vulva.

Question 1

[Maximum number: 1]

The diagram shows the male reproductive system in front view.

Figure for Question 1 — IB Biology SL

Which structures are indicated by the letters X, Y and Z ?

X

Y

Z

testis

sperm duct

seminal vesicle

epididymis

sperm duct

prostate gland

testis

urethra

prostate gland

epididymis

urethra

seminal vesicle

Exam points

  • Identify FSH and LH as pituitary hormones; link the LH rise to follicle rupture and ovulation.
  • Trace FSH and oestradiol from follicle growth to ovulation, then corpus luteum progesterone to endometrium.
  • Sketch oestrogen and progesterone curves from days 13–28, showing their distinct rises and falls.

Question 1

[Maximum number: 1]

What is a function of luteinizing hormone (LH) in the female menstrual cycle?

A

To promote secondary sexual characteristics

B

To inhibit progesterone secretion

C

To stimulate the follicle to release estrogen

D

To trigger ovulation

Exam points

  • Identify breakdown of sperm and egg nuclear membranes during human fertilization.

Question 1

[Maximum number: 1]

What happens during fertilization in humans?

A

The nuclear membranes of sperm and egg break down.

B

The sperm enters the egg.

C

The chromosomes undergo joint meiosis.

D

Mitochondria in the zygote come from sperm and egg.

Exam points

  • Explain how cycle-suppressing drugs and FSH treatment prepare multiple follicles for egg collection in IVF.
  • Outline IVF from egg collection and fertilization outside the body through embryo culture and transfer to the uterus.

Question 1

[Maximum number: 1]

In preparation for IVF, women are first treated with drugs, followed by artificial doses of hormones. What is the purpose of each step?

Initial drug treatment

Artificial doses of hormones

stop menstrual cycles

facilitate fertilization of eggs

initiate endometrium development

allow multiple implantation

prevent FSH secretion

induce multiple ovulation

induce multiple ovulation

initiate endometrium development

Exam points

  • Define pollination as pollen transfer from anther to stigma.
  • Locate meiosis in anther/pollen and ovary/ovule tissues during flowering-plant reproduction.

Question 1

[Maximum number: 1]

A cross-section of a flower is shown.

Figure for Question 1 — IB Biology SL

What is structure Y?

A

Anther

B

Nectary

C

Style

D

Stigma

No public sample questions are available for this syllabus point yet.

Exam points

  • Explain how separate male and female flowers or plants (dioecy) prevent self-pollination and promote pollen transfer between plants.
  • Explain how different maturation times of male and female structures reduce self-pollination and promote cross-pollination.

Question 1

[Maximum number: 2]

The micrograph shows onion (Allium cepa) meristematic tissue.

Figure for Question 1 — IB Biology SL

Outline how cross-pollination can be promoted by flowering plants.

Exam points

  • Identify reduced inbreeding as the benefit of self-incompatibility alleles, without attributing it to a lower mutation rate or inhibited pollen release.

Question 1

[Maximum number: 1]

Cherry trees (Prunus avium) have two self-incompatibility alleles. What benefit do self-incompatibility alleles have?

A

They decrease genetic variation.

B

They prevent inbreeding.

C

They decrease the chances of mutations taking place within the gametes.

D

They prevent the plant from releasing pollen at certain times of the year.

No public sample questions are available for this syllabus point yet.