Revision Notes for CBSE Class 12 Biology Chapter 1 (Reproduction in Organisms) - Free PDF Download





















FAQs on Reproduction in Organism Class 12 Notes CBSE Biology Chapter 1 (Free PDF Download)
1. What is the Process of Gametogenesis?
Gametogenesis is the process of creation of female and male gametes. They are a form of haploid cell that may look the same or sometimes different in structure. In algae, it is found to have similar properties, also called as homogametic. An organism like a human, which falls in higher-level, two morphologically separate cells or gametes is produced. This is called heterogametes, while sperms become the male gametes and ovum is the female gamete.
It is seen that gametes have a half set of chromosomes irrespective of an organism having a diploid cell. A diploid organism like gymnosperms, angiosperms, pteridophytes, makes use of meiotic division to produce offspring. This category ideally includes fungi, algae, and bryophytes.
2. What are the Properties of an Oestrous Cycle?
An oestrous cycle is a part of the female reproductive system, which is followed by menstruation. Here are some properties of this cycle.
This cycle ideally occurs in an organism like dog, deer, tiger, cow, etc. who are non-primitive.
This cycle stays for a short period and produces heat in the body. In animals like a cow, this phenomenon can last upto 24 hours which is followed by an anoestrus.
In this cycle, menstruation blood doesn’t flow; instead, a bust endometrium is absorbed.
The copulation process in females can be successful during this period.
Hormones are responsible for the regulation of reproductive processes. This also conducts the transition phases in animals and plants.
3. Define the Process of Gamete Transfer in Reproduction?
It is seen that in the majority of organisms, gametes are non-motile, which is part of a male and female human. At the same time, motile gametes are a part of algae and fungi. In the case of plants like algae, fungi, bryophytes and pteridophytes male and female gametes move through the water. Here the male gametes are more in numbers than female as sperms are required to pass through female vaginal fluid.
In higher plants, pollen grains carry male gametes to seeds. Pollen grains are transferred through air, birds, or natural phenomenon. This transfer goes from another stigma to ovule, also known as pollination. Pollen grains sprout on stigma to create a pollen tube that distributes the male gametes next to the ovule.
4. Why is reproduction important according to Chapter 1 of Class 12 Biology?
Reproduction refers to the process of producing similar offspring by the parents. It is an important process needed for the continuity of a particular race. When the offspring grow, they produce new offspring. In this way, the cycle continues. Reproduction is important for the existence of life on the earth. It also helps in differentiating the different organisms present on the earth. Producing organisms of similar species is not possible without reproduction.
5. How will you differentiate asexual and sexual reproduction?
Asexual reproduction is the process in which only one parent takes part in producing offspring. The offspring is produced by a single parent and it is the same as the parent cell. Sexual reproduction involves two parents. The offspring is produced by fertilization of a male and female reproductive cell. The offspring produced in sexual reproduction may not look exactly similar to the parent cell. To learn more about this, refer to Vedantu’s Class 12 Biology Chapter 1 Revision Notes.
6. How can I download the Class 12 Biology Chapter 1 notes PDF?
Yes, students of Class 12 can download Chapter 1 Biology notes online. They can visit the Vedantu website or app to download the Class 12 Biology notes. Notes of all chapters of Class 12 Biology are available online to help students to prepare for the final board exams. All NCERT Solutions are also available in the notes for easy understanding of the chapters. Students can save the Biology notes on their computers and refer to them during the exams.
7. Discuss the different ways of asexual reproduction discussed in Chapter 1 of Class 12 Biology?
Asexual reproduction can take place by different methods. Some of the common methods of asexual reproduction include binary fission, vegetative propagation, budding, and fragmentation. There are different methods of asexual reproduction by which organisms reproduce and produce similar young one. Only a single parent is required for asexual reproduction. The offspring produced during asexual reproduction looks the same as the parent cell because only a single parent is involved in producing a new young one.
8. What is the significance of sexual reproduction?
Sexual reproduction is important for the sustenance of life. It is the process in which two parents take part to produce offspring. The offspring consists of half cells from each parent cell. The offspring may not look the same but it carries similar genes as from the parent cells. It is an important process needed to produce the offspring of similar species. Sexual reproduction is also important to carry on one particular type of species in the future.