Fertilisation and Development Practice Questions
20 free Fertilisation and Development practice questions for the NCERT Biology. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Fertilisation is defined as the process of:
- A Formation of gametes in gonads
- B Fusion of male and female gametes
- C Development of the embryo post-zygote
- D Formation of the zygote nucleus only
Correct answer: Fusion of male and female gametes
Fertilisation involves the fusion of male and female gametes. This fusion results in the formation of a diploid zygote.
Which type of fertilisation occurs outside the body of the organism?
- A Internal fertilisation (inside body)
- B External fertilisation (outside body)
- C Cross fertilisation between mates
- D Self fertilisation within one organism
Correct answer: External fertilisation (outside body)
External fertilisation occurs when gametes fuse outside the body. It is common in aquatic animals like fishes and frogs.
Which animal group most commonly shows internal fertilisation?
- A Fishes
- B Amphibians
- C Reptiles
- D Echinoderms
Correct answer: Reptiles
Reptiles show internal fertilisation. This adaptation increases chances of survival on land.
The immediate product of fertilisation is the:
- A Embryo
- B Blastula
- C Zygote
- D Fetus
Correct answer: Zygote
Fusion of gametes produces a single-celled zygote. This cell later undergoes divisions to form an embryo.
Cleavage refers to:
- A Increase in the overall size of the embryo
- B Differentiation of embryonic tissues into layers
- C Repeated mitotic divisions of zygote
- D Formation of the three primary germ layers
Correct answer: Repeated mitotic divisions of zygote
Cleavage is the rapid mitotic division of the zygote. It increases cell number without increasing size.
Which stage of embryonic development is a hollow ball of cells?
- A Morula
- B Gastrula
- C Blastula
- D Zygote
Correct answer: Blastula
Blastula is a hollow structure formed after cleavage. It contains a fluid-filled cavity called blastocoel.
Formation of three germ layers occurs during:
- A Cleavage
- B Blastulation
- C Gastrulation
- D Organogenesis
Correct answer: Gastrulation
Gastrulation leads to formation of ectoderm, mesoderm, and endoderm. These layers give rise to all tissues and organs.
Which germ layer gives rise to the nervous system?
- A Endoderm
- B Mesoderm
- C Ectoderm
- D Blastoderm
Correct answer: Ectoderm
Ectoderm forms the nervous system and epidermis. It is the outermost germ layer.
Viviparous animals are those that:
- A Lay eggs that hatch externally
- B Show external fertilisation only
- C Give birth to fully developed young ones
- D Undergo complete metamorphosis
Correct answer: Give birth to fully developed young ones
Viviparous animals give birth to fully developed young ones. Development occurs inside the mother's body.
Oviparous animals are characterized by:
- A Undergoing internal embryonic development
- B Giving birth to live young ones
- C Laying eggs that develop externally
- D Reproducing without any fertilisation
Correct answer: Laying eggs that develop externally
Oviparous animals lay eggs. Embryonic development occurs outside the mother's body.
Which structure provides nourishment to the developing embryo in mammals?
- A Yolk sac
- B Placenta
- C Amnion
- D Chorion
Correct answer: Placenta
Placenta facilitates exchange of nutrients, gases, and wastes between mother and fetus. It supports embryonic development.
Which embryonic stage directly precedes gastrula?
- A Zygote stage
- B Morula stage
- C Blastula
- D Fetal stage
Correct answer: Blastula
Blastula is formed before gastrulation. Gastrulation reorganizes blastula cells into germ layers.
The process by which organs are formed from germ layers is called:
- A Cleavage division
- B Gastrulation process
- C Organogenesis
- D Blastulation phase
Correct answer: Organogenesis
Organogenesis involves differentiation of tissues into organs. It follows gastrulation.
Which of the following animals shows metamorphosis?
- A Human
- B Cow
- C Frog
- D Dog
Correct answer: Frog
Frog undergoes metamorphosis from tadpole to adult. This involves drastic structural changes.
In birds, the embryo develops inside the egg mainly due to:
- A Presence of placenta
- B Large amount of yolk
- C Internal fertilisation only
- D Lack of cleavage
Correct answer: Large amount of yolk
Yolk provides nutrition for the developing embryo. This supports complete development inside the egg.
Which membrane protects the embryo from mechanical shock?
- A Chorion
- B Amniotic sac
- C Allantois
- D Yolk sac
Correct answer: Amniotic sac
The amniotic sac (amnion) surrounds the embryo with amniotic fluid. This fluid cushions and protects the embryo.
Which hormone is mainly responsible for initiation of childbirth?
- A Progesterone
- B Estrogen
- C Oxytocin
- D Prolactin
Correct answer: Oxytocin
Oxytocin stimulates uterine contractions. These contractions lead to childbirth.
The period between fertilisation and birth in humans is called:
- A Menstrual cycle
- B Gestation period
- C Lactation period
- D Ovulation period
Correct answer: Gestation period
Gestation period refers to duration of embryonic and fetal development. In humans, it lasts about nine months.
Which structure in egg-laying animals helps in respiration of embryo?
- A Amniotic sac
- B Chorionic layer
- C Allantois
- D Yolk sac membrane
Correct answer: Allantois
Allantois functions in respiration and excretion. It facilitates gas exchange for the embryo.
Which statement best describes fertilisation and development in animals?
- A All animals rely on external fertilisation regardless of habitat
- B Embryonic development always occurs outside the mother's body
- C Fertilisation and development strategies vary across animal groups
- D Viviparity is found exclusively in aquatic animal species
Correct answer: Fertilisation and development strategies vary across animal groups
Animals show diverse modes of fertilisation and development. These adaptations are influenced by habitat and lifestyle.