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The flower - class-VIII

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Plants are able to produce fruits with the help of insects as they are

  1. Help in aestivation

  2. Help in pollination

  3. Help to overcome dormancy

  4. None of the above


Correct Option: B
Explanation:

Many flowers produce nectar, a sugary liquid that many insects eat. When an insect lands on a flower to feed, pollen grains stick to its body. As the insect moves to another flower of the same species, these pollen grains are transferred to the flower's stigma and pollination occurs. After pollination, the plants produce fruits.

So, the correct answer is 'Help in pollination',

Some plants having pleasant odour and attractive colours for

  1. Hydrophily

  2. Anemophily

  3. Entomophily

  4. None of the above


Correct Option: C
Explanation:

Entomophily is a form of pollination whereby pollen or spores are distributed by insects. These plants attract insects with vibrant colours and pleasant odour.

The flower of which of the following plant is zygomorphic?

  1. Bean

  2. Datura

  3. Mustard

  4. Canna


Correct Option: A
Explanation:
A flower can be cut into two equal parts vertically in one direction is called zygomorphic flower.

Bean - zygomorphic flower
Datura - actinomorphic flower
Mustard - actinomorphic flower
Canna - asymmetric flower

So, the correct option is 'Bean'.

Which of the following plant had developed an obligate symbiotic relationship with a moth called Tagetecula, in relation to pollination

  1. Amorphophallus

  2. Ficus

  3. Salvia

  4. Yucca


Correct Option: D
Explanation:

Yucca plant has developed an obligate symbiotic relationship with a moth called Tagetecula, in relation to pollination. Neither the yucca or the moth can survive without the other. The moth’s larvae depend on the seeds of the yucca plant for food, and the yucca plant can only be pollinated by the moth. 


So, the correct option is 'Yucca'.

Select erroneous pair


(A) Sweet potato - Bisexual flower
(B) Castor - Endospermic seed
(C) Vallisneria - Monoecious
(D) Zostera - Hypo hydrophily
(E) Poppy - multi carpellary apocarpous gynoecium.

  1. A & B

  2. B & D

  3. C & E

  4. A & D


Correct Option: A

................... is not unisexual flower.

  1. Coconut

  2. Papaya

  3. Gulmohar

  4. Water-melon


Correct Option: C
Explanation:

Unisexual flowers only have either the gynoecium or the androecium. Example of unisexual flowers are : Coconut, Papaya, Watermelon.

Bisexual flowers have both gynoecium and androecium.
Examples of bixesual flowers are : Hibiscus, Gulmohar, etc.
So the correct answer is ' Gulmohar'.

Bisexual flowers are found in?

  1. Raceme and catkins

  2. Spike and spikelet's

  3. Corymb and spadix

  4. Catkins and spadix


Correct Option: A

Which of the following is not an unisexual flower ? 

  1. Coconut

  2. Papaya

  3. Gulmohor

  4. Maize


Correct Option: C
Explanation:

 A flower that possesses either stamens or carpels but not both. are called a unisexual flower. coconut, maize, and papaya are unisexual flowers because at their development stage they either posses stamen or carpels. so, 'the correct option is Gulmohar'.

Choose odd one w.r.t. sexuality.

  1. Coconut

  2. Cucurbits

  3. Chara

  4. Papaya


Correct Option: D
Explanation:

Monecious Plants (mono meaning one) have male and female reproductive organs on the same plant. In other words, they are hermaphrodites. The organs may or may not be on the same flower (i.e. the flowers can be perfect or imperfect. Eg. Coconut, cucurbits, chara, etc. 

Dioecious Plants (di meaning two) have either male OR female flowers (not both). As a result, plants are either male OR female. Imperfect flowers only. Eg. Papaya, cannabis, etc. 

So, the correct option is 'Papaya'. 

Flowers which have stamens and pistils are called as

  1. Incomplete flowers

  2. Complete flowers

  3. Unisexual flowers

  4. Homosexual flowers


Correct Option: B
Explanation:

  1. A flower that lacks one or two of the four whorls is an incomplete flower.
  2. A complete flower has all four whorls calyx, corolla, stamens, and pistil are present.
  3. A unisexual flower has one of the reproductive organ either stamen or pistil is present.
  4. Homosexual flowers are not probable
So the correct option is "Complete flowers".

A complete flower produces

  1. Stamens

  2. Pistils

  3. Both A and B

  4. None of the above


Correct Option: C
Explanation:

A flower has four different whorls has calyx, corolla, stamen (male part) and pistil (female part) and if both reproductive parts are present in a flower than it is considered to be a complete flower.

So the correct option is "Both A and B".

Flowers are unisexual in.

  1. Cyathium

  2. Thyrsus

  3. Verticillaster

  4. Cyme


Correct Option: A
Explanation:

  • A unisexual flower is a flower that possesses either stamens or carpels. Cyathium looks like a single flower. 
  • It has a cup-shaped involucre formed by bracts encloses a single female flower and a number of male flowers.  
  • Thus it has unisexual flowers with each male flower are as a single stamen while a single pistil represents a female flower. 
  • Also, it is a type of cymose inflorescence. Other options are not as unisexual.
  • The correct option is A.

The number of whorls present in a bisexual flower is

  1. One

  2. Three

  3. Two

  4. Four


Correct Option: D
Explanation:

A bisexual flower is a flower that contains all the four whorls such as petals, sepals, the male reproductive structure (stamen) and female reproductive structure (pistil). Hence it is also called as a complete or perfect flower. Thus the correct answer is 'Four'.

The flowers are composed of 

  1. Petals, sepals, filament and carpel

  2. Sepals, petals, stamen and pistil

  3. Sepals, petals, anther and pistil

  4. Petals, sepals, ovary and anther


Correct Option: B
Explanation:

The whorl of the flower are differentiated into two categories essential and non-essential whorl and are consists of 

  1. Calyx which is considered as the outermost whorl and its unit is known as sepals and are green in colour helps in protection of flower.
  2. Corolla is the second nonessential unit and is composed of petals and are coloured and helps to attract pollinators.
  3. Stamens or androecium are the male reproductive part and responsible for the production of pollen grains (male gamete).
  4. Carpels, pistil or gynoecium are the female reproductive part and produce ovum (female gamete).

So, the correct option is 'Sepals, petals, stamen, and pistil'.

The female flowers are composed of the 

  1. Pistil, style and ovary

  2. Anther, stigma and filament

  3. Ovary, style and stigma

  4. Ovule, anther and stigma


Correct Option: C
Explanation:

Carpels, pistil or gynoecium are the female reproductive part of the flower that consists of a stigma that holds the pollen grains, a style that leads the path of pollen tube and ovary produce ovum (female gamete). The flower that has the only pistil is referred to as female flower.

So, the correct option is 'Ovary, style and stigma'

Choose the correct statement from the following.

  1. Cleistogamous flowers always exhibit autogamy

  2. Chasmogamous flowers always exhibit geitonogamy

  3. Cleistogamous flowers exhibit both autogamy and geitonogamy

  4. Chasmogamous flowers never exhibit autogamy


Correct Option: A
Explanation:

Cleistogamous flowers (that do not open at all) always exhibit autogamy, whereas chasmogamous flowers(with exposed anthers and stigma) can exhibit autogamy, geitonogamy or xenogamy.

The male flowers are 

  1. The flowers which contain only the anther

  2. The flowers which contain the stamen

  3. The flowers which contain filament

  4. The flowers which contain only the pistil


Correct Option: B
Explanation:

Stamens or androecium are the male reproductive part  contains filament which is aslender stalk and anther is bilobed and responsible for the production of pollen grains (male gamete).The flower with stamens is referred to as male flower.

So the correct option is "The flowers which contain the stamen".

Statement $1$ : Unisexual flowers are either staminate flowers or pistillate flowers.
Statement $2$ : Both monoecious and dioecious plants have unisexual flowers.

  1. Both statement $1$ and $2$ are correct

  2. Statement $1$ is correct but statement $2$ is incorrect

  3. Statement $1$ is incorrect but statement $2$ is correct

  4. Both statement $1$ and $2$ are incorrect


Correct Option: B
Explanation:

In flowering plants, the unisexual male flower is staminate, i.e., bearing stamens, while the female flower is pistillate i.e., bearing pistils. In some flowering plants, both, and female may be present on same individual (monoecious) or on separate individuals (dioecious).

So, the correct option is 'Statement 1 is correct but statement 2 is incorrect'.

Consider the following statements and select the option that correctly fills the blanks.

  1. Mucor mucedo is _____ fungi.
  2. China rose plant bears ________ flowers.
  3. Marchantia is a _______ bryophyte.

  1. Homothallic , Bisexual and Dioecious

  2. Heterothallic, Bisexual and Dioecious

  3. Heterothallic, Unisexual and Monoecious

  4. Homothallic and Unisexual and Monoecious


Correct Option: A
Explanation:

  1. Mucor mucedo is homothallic (self-compatible ) fungi.
  2. China rose or Hibiscus flower has both stamen and pistil present on the same plant so it bears a bisexual flower.
  3. In Marchantia is a liverwort in which male and female are born on different plants so it is dioecious bryophyte.
So the correct option is  'Homothallic, Bisexual and Dioecious'

If a water soaked seed is pressed, a small drop of water comes out through the ...............

  1. Stomata

  2. Lenticel

  3. Micopyle

  4. Radicle


Correct Option: C
Explanation:

When a soaked seed is pressed the water comes out from the pore of the seed which is known as the micropyle.

Stomata and lenticels are not present in the seed.
Radical is a part of the seed which will develop into the roots.
So the correct answer is ' Micropyle'.

Root system grows from

  1. Embryo of seed

  2. Radicle of embryo

  3. Plumule of embryo

  4. Coleoptile


Correct Option: B
Explanation:

Roots system develops from the radicle of the embryo because in seed, the radicle grows downward into the soil to absorb water and nutrients from the soil.

So, the correct option is 'Radicle of embryo'.

............. is not unisexual flower.

  1. Coconnut

  2. Papaya

  3. Gulmohar

  4. Watermelon


Correct Option: C
Explanation:

The flowers wherein both the sex-organs, that is, the stamen and the pistil are present is called the bisexual or the hermaphroditic flowers. Those flowers wherein, only one of the sex-organ is present and the other is rudimentary absent, are called uni-sexual flowers. These can be pistillate when only pistil is present and can be staminate when only stamen is present.

Gulmohar is not unisexual. It is a bisexual flower.
So, the correct answer is 'Gulmohar'

Which of the following plants have unisexual flowers?

  1. Datura

  2. Hibiscis

  3. Rose

  4. Papaya


Correct Option: D
Explanation:
  • Hibiscus, Rose, and Datura have bisexual flowers with both stamens and carpel.
  • Papaya has unisexual flowers, male flowers, and female flowers are on separate plants.
  • So, the correct answer is 'Papaya'.
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