Nootan solutions for बायोलॉजी [अंग्रेजी] कक्षा १२ आयसीएसई chapter 1 - Reproduction in Organisms [Latest edition]

Offspring produced by vegetative propagation are ______.

After fertilization, fruit is derived from ______.

The process of pollen transfer from anther to stigma of a flower is known as ______.

Mint multiplies vegetatively by ______.

An example of a dioecious plant is ______.

An example of a monoecious plant is ______.

A fruit is ______.

Development of a new plant from a tissue or structure that drops or is separated from the parent plant is called ______.

Which one of the following statements is true for cucurbits?

Which of the following statements is true for date palm?

Which of the following is a post-fertilization event in flowering plants?

The phenomenon wherein, the ovary develops into a fruit without fertilisation is called ______.

A population of asexually reproduced, genetically identical individuals is a ______.

The plants obtained from pollen are genetically ______.

State whether the following statement is true or false.

A clone is a group of genetically identical individuals developed as a result of sexual reproduction.

State whether the following statement is true or false.

Formation of fruit without fertilization is called parthenogenesis.

State whether the following statement is true or false.

Offspring formed as a result of external fertilization have better chance of survival than those formed inside an organism.

State whether the following statement is true or false.

Offspring formed by sexual reproduction exhibit more variation than those formed by asexual reproduction.

State whether the following statement is true or false.

There is no natural death in single-celled organisms.

Name the organism that reproduce through the following reproductive structure: 

conidia

Name the organism that reproduce through the following reproductive structure: 

zoospores

Mention one similarity between conidia and zoospores.

Mention one difference between conidia and zoospores.

All papaya plants bear flowers but fruits are seen in some. Why?

Name the artificial means of vegetative propagation.

What is a clone?

Why are pollen grains produced in enormous quantity in maize?

Pieces of a Bryophyllum leaf when put into wet soil produce new plants. How?

Name the unit of vegetative propagation in grasses.

Name the unit of vegetative propagation in water hyacinth.

Why are living plant cells said to be totipotent?

Write the two pre-fertilization events from the list given below:

Syngamy, Gametogenesis, Embryogenesis, Pollination

A potato plant is infected with a virus. Name a method to obtain virus-free potato plants from it.

Name the vegetative propagule in the following:

Agave

Name the vegetative propagule in the following:

Bryophyllum

Why do moss plants produce very large number of male gametes? Provide one reason. What are these gametes called?

Banana crop is cultivated by farmers without sowing of seeds. Explain how the plant is propagated?

What is the major difference you observe in the offsprings produced by asexual reproduction and in the progeny produced by sexual reproduction?

Name the mode of reproduction that ensures the creation of new variants.

Name an organism where cell division is itself a mode of reproduction.

Give one example of a fungus which reproduces by budding.

Give one example of a fungus which reproduces by conidia.

Write the name of the organism that is referred to as the ‘Terror of Bengal’.

Mention the unique flowering phenomenon exhibited by Strobilanthus kunthiana (neelakuranaji).

Name a plant which flowers every twelve years.

Cucurbits and papaya plants bear staminate and pistillate flowers. Mention the categories they are put under separately on the basis of the type of flowers they bear.

Mention the unique feature with respect to flowering and fruiting in bamboo species.

All date-palm trees bear flowers but fruits are seen in some. Explain.

Name the type of cell division that takes place in the zygote of an organism exhibiting haplontic life cycle.

How does Penicillium reproduce asexually?

Name the kind of reproduction in bees in which drones are produced.

State the difference between meiocyte and gamete with respect to chromosome number.

Name the phenomenon where the female gamete directly develops into a new organism with an avian example.

Name the common phenomenon with reference to reproduction in rotifers, honey bees and turkey.

A male honeybee has 16 chromosomes whereas its female has 32 chromosomes. Give one reason.

Name any two organisms and the phenomenon involved where the female gamete undergoes development to form new organisms without fertilization.

How many chromosomes do drones of honey bees possess?

Name the type of cell division involved in the production of sperms by honey bees.

Give one example of an animal which exhibits oestrus cycle.

Why do we refer to offspring formed by asexual method of reproduction as clones?

Between an annual and a perennial plant, which one has a shorter juvenile phase? Give one reason.

Rearrange the following events of sexual reproduction in the sequence they occur in a flowering plant:

Embryogenesis, Fertilisation, Gametogenesis, Pollination.

In haploid organisms that undergo sexual reproduction, name the stage in the life cycle when meiosis occurs. Give reasons for your answer.

The meiocyte of rice has 24 chromosomes. Write the number of chromosomes in its endosperm.

In which two of the following organisms is the fertilization external?

Cartilaginous fishes, Bony fishes, Frog, Birds.

With which type of reproduction do we associate the reduction division?

A moss plant is unable to complete its life cycle in a dry environment. State two reasons.

The male gametes of rice plant have 12 chromosomes in their nucleus. How many chromosome number will be in the female gamete, zygote and the cells of the seedling?

The number of chromosomes in the shoot tip cells of a rice plant is 20. What would be the number of chromosomes in the microspore mother cells of the same plant?

‘Fertilisation is not an obligatory event for fruit production in certains plants’. Explain the statement.

If a certain plant when introduced into a new environment neither it produces seeds nor responds to vegetative propagation. How can more plants of its kind be produced from this plant? Describe the method in brief.

If the haploid number of chromosomes in a plant species is 20, how many chromosomes will be present in the cells of the shoot tip?

Name the terminal stage of ageing in the life cycle of plants.

List the three stages the annuals and biennial angiosperms have to pass through during their life cycle.

List any two vegetative propagules in flowering plants.

Give a significant point of difference between the oestrous and menstrual cycles.

How many chromosomes are present in meiocytes of a fruit fly?

Some crop plants can be grown from a seed as well as vegetatively from stem cuttings. List any four advantages of vegetative propagation in such cases.

Name two unique features regarding the reproduction of flowering plants.

State the three advantages of vegetative reproduction.

State two disadvantages of vegetative propagation?

Describe the events that take place between pollination and fertilization in plants.

Give four points to show the importance of vegetative propagation.

Define lifespan.

Give the life span of an elephant. 

What are seasonal breeders?

Give an example of seasonal breeders?

How is the chromosome number maintained in sexually reproducing organisms?

The life span of rice plant is ______.

Which of the following organisms is a seasonal breeder?

The phase of life cycle of an organism which is characterised by gradual deterioration of vital capacities is called ______ phase.

A single pea plant in your kitchen garden produces pods with viable seeds, but the individual papaya plant does not. Explain.

The number of species exhibiting asexual reproduction is drastically reduced in higher organisms as compared with lower organisms. Can you assign any possible reason for this situation?

Why is reproduction essential for organisms?

Which is a better mode of reproduction sexual or asexual? Why?

Which is a better mode of reproduction sexual or asexual? Why?

Offspring formed due to sexual reproduction have better chances of survival. Why? Is this statement always true?

How does the progeny formed from asexual reproduction differ from those formed by sexual reproduction?

Distinguish between asexual and sexual reproduction.

Why is vegetative reproduction also considered as a type of asexual reproduction?

What is vegetative propagation? 

Give two suitable examples of vegetative propagation.

Define Juvenile phase.

Define reproductive phase.

Define senescent phase.

Higher organisms have resorted to sexual reproduction in spite of its complexity. Why?

Explain why meiosis and gametogenesis are always interlinked?

Identify each part in a flowering plant and write whether it is haploid (n) or diploid (2n).

1. Ovary
2. Anther
3. Egg
4. Pollen
5. Male gamete
6. Zygote

Define external fertilization.

Mention the disadvantages of external fertilization.

Differentiate between a zoospore and a zygote.

Differentiate between gametogenesis from embryogenesis.

Describe the post-fertilization changes in a flower.

What is a bisexual flower?

Collect five bisexual flowers from your neighborhood and with the help of your teacher find out their common and scientific names.

Examine a few flowers of any cucurbit plant and try to identify the staminate and pistillate flowers. Do you know any other plant that bears unisexual flowers?

Why are offspring of oviparous animals at a greater risk as compared to offspring of viviparous animals?

Difference between an annual and biennial plants. Provide one example of each.

Differentiate between monoecious and dioecious plants.

Differentiate between parthenocarpy and parthenogenesis. Give one example of each.

List any two differences between pollination and fertilization.