Start learning →

ISC Class 12 Reproduction in Organisms & Plants — practice questions — page 3

Explore 98 free Reproduction in Organisms & Plants questions in ISC Class 12 Biology. Open each question or exercise to read its content, reference answers and available explanation.

Practise Reproduction in Organisms & Plants with Quill →

Reproduction in Organisms & Plants questions and exercises with answers

Showing questions 61–90 of 98.

Parturition is triggered by which hormone?Read the answer and worked solution →True or false: human reproductionRead the answer and worked solution →Male or female structure?Read the answer and worked solution →Reading the termsRead the answer and worked solution →Spot the odd one outRead the answer and worked solution →Colostrum (the first milk after childbirth) is rich in:Read the answer and worked solution →LH surge in the menstrual cycle triggers:Read the answer and worked solution →A single spermatogonium ultimately produces how many functional sperm cells?Read the answer and worked solution →The first milk produced after birth, rich in antibodies, is calledRead the answer and worked solution →The hormone that drives uterine contractions during childbirth (parturition) is:Read the answer and worked solution →Ovulation in a typical 28-day human menstrual cycle occurs around dayRead the answer and worked solution →The hormone detected by home pregnancy tests isRead the answer and worked solution →NEET · Bio · Human Reproduction · Sperm Structure PartsRead the answer and worked solution →NEET · Bio · Human Reproduction · Fertilisation Term — Gap FillRead the answer and worked solution →Flip and pair: term with meaningRead the answer and worked solution →NEET · Bio · Human Reproduction · Hormone to Source GlandRead the answer and worked solution →True or false: evidence for evolutionRead the answer and worked solution →NEET · Biology · Tap the STIsRead the answer and worked solution →Order the sequence the chapter sets outRead the answer and worked solution →OriginsRead the answer and worked solution →HIV (Human Immunodeficiency Virus) primarily attacks which cells of the immune system?Read the answer and worked solution →Which contraceptive method ALSO prevents sexually transmitted infections?Read the answer and worked solution →Two true, one falseRead the answer and worked solution →Spot the odd one outRead the answer and worked solution →Amniocentesis was BANNED for sex-determination purposes in India by:Read the answer and worked solution →Oral contraceptive pills (OCPs) work primarily by:Read the answer and worked solution →A typical angiosperm embryo sac hasRead the answer and worked solution →NEET · Bio · Human Reproduction · Uterus RegionRead the answer and worked solution →Human pregnancy lasts approximately:Read the answer and worked solution →Spermatogenesis occurs in the:Read the answer and worked solution →

Worked practice questions

Parturition is triggered by which hormone?

  1. Estrogen
  2. Oxytocin
  3. Insulin
  4. Thyroxine
Show answer and solution

Correct answer: B. Oxytocin

Parturition is the process of giving birth (childbirth). It is induced by a complex neuroendocrine mechanism. The process begins with signals originating from the fully developed fetus and the placenta, which induce mild uterine contractions known as the **fetal ejection reflex**. This reflex triggers the release of **oxytocin** from the maternal posterior pituitary gland. Oxytocin acts on the uterine muscles (myometrium), causing stronger contractions. These contractions, in turn, stimulate further secretion of oxytocin. The stimulatory reflex between the uterine contraction and oxytocin secretion continues, resulting in increasingly stronger contractions, which eventually leads to the expulsion of the baby out of the uterus through the birth canal.

Open this question →

True or false: human reproduction

Read exercise and reference answers
Questions
  1. Statement is true
    Yes
    Statement
    Humans reproduce sexually.
  2. Statement is true
    Yes
    Statement
    Fertilisation produces a zygote.
  3. Statement is true
    Yes
    Statement
    Gametes are produced by meiosis.
  4. Statement is true
    No
    Statement
    A zygote has the same chromosome number as a gamete.
  5. Statement is true
    Yes
    Statement
    The embryo develops from the zygote.
The chapter's framework. Source: syllabus Biology, Human Reproduction.

Open this exercise →

Male or female structure?

Read exercise and reference answers
Items
  1. Item
    Testis
    Category
    Male
  2. Item
    Produces sperm
    Category
    Male
  3. Item
    Ovary
    Category
    Female
  4. Item
    Produces the ovum
    Category
    Female
Categories
  1. Item
    Male
  2. Item
    Female
The two reproductive systems. Source: syllabus Biology, Human Reproduction.

Open this exercise →

How to practise

  1. Choose a Reproduction in Organisms & Plants question and try to work out your answer.
  2. Open the question to check the correct answer and read its worked solution.
  3. Continue in the app for bite-sized lessons, explanations and review with Quill. You can start without creating an account.

Put it into practice

Continue with Reproduction in Organisms & Plants practice for ISC Class 12. Read explanations as you go. No signup form needed to start.

Practise Reproduction in Organisms & Plants →

More Biology topics

Genetics and EvolutionBiotechnology and ApplicationsBiology in Human Welfare & HealthEcology and Environment