Science Olympiad Test: Reproduction in Organism- 2 - Class 10 MCQ

Flower as Reproductive part of Plant:

• The flower is the reproductive organ of the plant.
• Flowers can be of two types - Unisexual flower & Bisexual flower
• Unisexual Flower- A flower with only one reproductive structure, male or female, is considered a unisexual flower. 
• Bisexual Flower- A flower that includes both a male and a female reproductive structure (stamen and pistil) is considered a bisexual flower. 

Bisexual Flowers:

• The flowers which contain both male and female reproductive organs are known as full or bisexual flowers.
• They will self-pollinate themselves.
• Examples: Tulip, Hibiscus, Mustard, and Lily.

Unisexual Flowers:

• The flowers which include only the male or female reproductive organs are called unisexual flowers.
• They are called incomplete flowers.
• To reproduce they undergo cross-pollination.
• Examples: Papaya, White mulberry, Corn, and Watermelon.

The exchange of nutrients, oxygen and waste products between the embryo and the mother's body takes place through the umbilical cord.

Oviducts is the tube through which an ovum or egg passes through the ovary.

Reproduction is essential for all organisms for continuation of the species generation after generation and to maintain a steady species population, so that, it does not become extinct.

The genetically identical offsprings formed by asexual reproduction are called clones.

• Unisexual flowers are those, which bear only male or female flowers, but never both together.  They can either possess stamen or pistil.
• As only one sex is present, it undergoes cross-fertilization, where gametes are produced by two different plants. 
• Fruit develops from the female flower and hence, fruit cannot be produced by the unisexual plants which possess male flowers (stamen).

Thus, the correct answer is option (c), '(ii), (iii) and (iv)'.

Planaria are free-living flatworms that live in quiet ponds or bodies of water. They have the unique ability to regenerate, meaning they can re-grow the new tissue to replace lost or injured tissue.

Y represents the testes that produce sperms and V represents the prostrate gland that produces seminal fluid.

Fertilisation is the fusion of two gametes in a sexual reproduction. It produces genetically different offsprings and does not lead to the formation of clones.

The sperms are produced in the Testis, stored in the epididymis and transported to the urethra through vas deferens.
So, the correct sequence is
'testis → vasdeferens → urethra'

Length of pollen tube depends upon distance of pollen on stigma and ovule because after pollination pollen germinates and form pollen tube that reaches upto ovule in ovary and release male gamete to fuse with female gamete.

The reproductive cells contain only half the number of chromosomes as compared to the normal body cells of an organism. The human sperm and egg have 23 chromosomes each. So when they fuse together, the zygote formed has 23 + 23 = 46 chromosomes. So the required ratio is 46 : 23, i.e., 2 : 1.

Gonorrhea, syphilis and chlamydia are examples of STIs that are caused by bacteria.

In binary fission, a single-celled organism divides into two daughter cells that are identical to their parent.

Visceral leishmaniasis (VL), also known as kala-azar, black fever, and Dumdum fever, is the most severe form of leishmaniasis and, without proper diagnosis and treatment, is associated with high fatality. Leishmaniasis is a disease caused by protozoan parasites of the genus Leishmania.