Tag: botany

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Questions Related to botany

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Insect's eggs are

  1. Microlecithal and centrolecithal

  2. Megalecithal and isolecithal

  3. Megalecithal and centrolecithal

  4. Megalecithal and telolecithal
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Enormous amount of yolk is present in megalecithal eggs and here yolk is several times greater than cytoplasm and yolk is concentrated in the interior of the egg and the cytoplasm is distributed as a thin layer on the outside of the yolk in centrolecithal eggs. These type of eggs is a characteristic of insects. Hence, option C is correct.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

The egg of frog is

  1. Microlecithal

  2. Mesolecithal

  3. Centrolecithal

  4. Alecithal
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Mesolecithal egg are those eggs that has a yolk of intermediate size and strongly concentrated in one hemisphere. The young hatch at a later stage of development. It is a characteristic of lung fishes and amphibians likes frog. Hence, option B is correct.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Eggs of birds are

  1. Microlecithal

  2. Centrolecithal

  3. Megalecithal

  4. Alecithal
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Enormous amount of yolk is present in megalecithal eggs and here yolk is several times greater than cytoplasm. These eggs may be small or big. These types of eggs are characteristics of of teleost fishes, reptiles, birds. Yolk of egg is used for two purposes; supply of energy and synthesis of the products required for elaboration of the embryonic body.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

The process in which new organisms are formed by existing organism is called as ___________

  1. Reproduction

  2. Growth

  3. Development

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

  • Reproduction is the biological process in which new individual organisms 'offsprings' are produced from their parents (existing organisms).
Growth is the process of increasing in physical size.
  • Development is the act or process of growing or causing something to grow or become larger or more advanced.

Therefore, the correct answer is option A.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Which one of the following mutations is not hereditary?

  1. Gametic

  2. Zygotic

  3. Somatic

  4. Genetic
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Mutations are the permanent changes in the nucleotide sequence of the genome of an individual. These can occur during replication of DNA or its exposure with radiations or carcinogens, etc.

Somatic mutations occur in somatic cells, also known as non-reproductive cells. The genes in these cells are non-heritable and hence any mutations the will not be passed to next generations. The only mutations that are inherited if they occur in gametes (eggs and sperm). Such mutations that occur in gametes are also called germ-line mutations.
So, the correct option is 'Somatic'.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Number of spermatozoa, a single primary spermatocyte ultimately produced in spermatogenesis is

  1. 1

  2. 2

  3. 4

  4. 8
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
The immature male germ cells (spermatogonia) produce sperms by spermatogenesis that begins at puberty. The spermatogonia present on the inside wall of seminiferous tubules multiply by mitotic division and increase in numbers. Each spermatogonium is diploid and contains 46 chromosomes. Some of the spermatogonia called primary spermatocytes periodically undergo meiosis. A primary spermatocyte completes the first meiotic division (reduction division) leading to the formation of two equal, haploid cells called secondary spermatocytes, which have only 23 chromosomes each. The secondary spermatocytes undergo the second meiotic division to produce four equal, haploid spermatids. 
Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

The life span of a dog is 

  1. 16 - 18 days

  2. 16 - 18 weeks

  3. 16 - 18 months

  4. 16 - 18 years
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The life span of dog is 16 - 18 years. Life expectancy in dogs can be affected by many factors including genetic disease, diet, and exercise, similar to humans. Life expectancy usually varies within a range. For example, a Beagle (average life expectancy 13.3 years) usually lives to around 12–15 years, and a Scottish Terrier (average life expectancy 12 years) usually lives to around 10–16 years.

So, the correct answer is '16 - 18 years'

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

A natural method of birth control assumes that sperms live for three days after intercourse, ovulation occurs between days $13-15$ of the menstrual cycle and released ova live for $36$ hours.
On which day of the cycle should intercourse not result in pregnancy?

  1. Day $7$
  2. Day $10$
  3. Day $12$
  4. Day $16$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A woman is fertile, on average, between the ages of $12$ to $15$. During these fertile years, a recurring process - known as the menstrual cycle - takes place each month. This involves the lining of the uterus preparing for pregnancy. If pregnancy does not occur, the lining breaks down and the woman has a period. This is also known as menstruation. During this period which is generally from day $1$ to the day $7$ of the cycle, the intercourse does not result in pregnancy.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Which statement describes human cells formed by meiosis?

  1. They are genetically identical and they become gametes.

  2. They are genetically identical and they become tissues.

  3. They are not genetically identical and they become gametes.

  4. They are not genetically identical and they become tissues.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In women, both sex chromosomes are the same and are therefore called as XX. In males, they are different and called as XY. When sperm and eggs (ova) are made during meiosis they separate to form different gametes. As women have XX, their eggs always carry the X chromosomes. As males have XY, approximately half their sperm carry the X chromosome while the remainder carries the Y chromosome.

Multiple choice botany modes of reproduction why do plants reproduce? reproduction and variation the life cycle of plants

Which of the following is associated with reproduction?

  1. Parthenogenesis

  2. Fertilization

  3. STDs

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Parthenogenesis is a natural form of asexual reproduction in which growth and development of embryos occur without fertilization.
Fertilization is the action or process of fertilizing an egg or a female animal or plant, involving the fusion of male and female gametes to form a zygote.
STDs stands for sexually transmitted disease. It is the infection transmitted through sexual contact, caused by bacteria, viruses or parasites.
So, the correct answer is option D.