Choose the correct alternative
Mitosis/meiosis and fertilization are two important processes involved in sexual reproduction in angiosperms which collectively maintain the chromosome number constant from generation to generation.

Both Meiosis and Fertilization are essential to maintain chromosome number, constant. Why?

Which of the following statements, support the view that elaborate sexual reproductive process appeared much later in the organic evolution. Lower groups of organisms have simpler body design Asexual reproduction is common in lower groups Asexual reproduction is common in higher groups of organisms The high incicdence of sexual reproduction in angiosperms and vertebrates. Choose the correct answer from the options given below:

ASSERTION TYPE QUESTIONS : These questions consist of two statements each, printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following four responses. A. If both Assertion and Reason are true and Reason is correct explanation of Assertion. B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion. C. If Assertion is true but Reason is false. D. If both Assertion and Reason are false. . Assertion : If an endosperm cell of angiosperm contains 24 chromosomes, the number of chromosomes in each cell of rootwill be 16. Reason : As endosperm is triploid and root cells are diploid, the chromosome number in each of root cell will be 16.

NCERT Exemplar Questions A few statements with regard to sexual reproduction are given below: Sexual reproduction does not always require two individuals Sexual reproduction generally involves gametic fusion Meiosis never occurs during sexual reproduction External fertilisation is a rule during sexual reproduction. Choose the correct statements from the options below:

Prior to a sports event blood & urine sample of sports persons are collected for drug tests. Write the generic names of two plants from which these drug are obtained.

Long Answer Questions Five mark Each QUESTIONS FROM CBSE BOARD EXAMINATIONS : A flower of tomato plant following the process of sexual reproduction produces 240 viable seeds. Answer the following questions giving reasons: (a) What is the minimum number of pollen grains that must have been involved in the pollination of its pistil? (b) What would have been the minimum number of ovules present in the ovary? (c) How many megaspore mother cells were involved? (d) What is the minimum number of microspore mother cells involved in the above case? (e) How many male gametes were involved in this case?

Long Answer Questions Five mark Each QUESTIONS FROM CBSE BOARD EXAMINATIONS : Fertilization is essential for production of seed, but in some angiosperms seeds develop without fertilization. (i) Give an example of an angiosperm that produces seeds without fertilization. Name the process. (ii) Explain the two ways by which seeds develop without fertilization.

These questions consist of two statement each, printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following four responses. A. If both Assertion and Reason are true and Reason is a correct explanation of the Assertion. B. If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion. C. If Assertion is true but Reason is false. D. If both Assertion and Reason are false. Assertion: Algae are characterized by multicellular sex organs in which every cell forms the gamete. Reason: Sexual reproduction in algae is only of oogamous type.