Biology · Science General

Botany and Plant Science

4,989 Questions

Botany and plant science delve into the biological study of plant life, covering structural anatomy, physiological processes, and reproductive mechanisms. Key topics include inflorescence patterns, root modifications, and seed development, which are vital for biology sections in medical entrance exams. This collection of practice questions helps solidify understanding of complex plant functions.

Plant ReproductionPlant AnatomyRoot ModificationsInflorescence PatternsPlant Morphology

Botany and Plant Science Questions

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Colour of Bougainvillea is due to 

  1. Coloured sepals

  2. Coloured bracts

  3. Coloured petals

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Bougainvillea plant is so colourful due to the magenta bracts. Three flowers are borne at each stem node, with flowers surrounded by three bracts, resulting in thick plant coverage with masses of color. Color is due to papery bracts, that enclose the true slender tubular white flowers. Bract colors can be white, pale to deep pink, magenta, various shades of red, purple, mauve, lavender, gold, peach, orange, salmon and some color combinations. Colors can change as bracts age and can be deeper or paler depending on where the plant is grown
So, the correct answer is 'Coloured bracts'
Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Glumes represent

  1. Bracts

  2. Sepals

  3. Petals

  4. Stamens
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Glumes represent bracts. Glumes are a basal, membranous, outer sterile husk or bract in the flowers of grasses (Poaceae) and sedges (Cyperaceae). A bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger or of a different colour, shape or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals. 
Thus, the correct answer is option A.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Autogamy can occur in a chasmogamous flower if.

  1. Pollen matures before maturity of ovule

  2. Ovules mature before maturity of pollen

  3. Both pollen and ovules mature simultaneously

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Autogamy is pollination within a flower. Chasmogamous flowers are those in which anthers and stigma are exposed. For autogamy, in such a flower to take place, pollen and ovule should mature simultaneously and anther and stigma should lie close to each other.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Non-essential floral organs without differentiation of calyx and corolla are called ________.

  1. Thalamus

  2. Pedicel

  3. Perianth

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

The non-essential parts of the flower are those that are not involved in the process of fertilization directly. These are called the accessory whorls. The calyx (made up of sepals) and corolla (made up of petals) represent the accessory whorls. In some flowers, the calyx and corolla are not differentiated or distinct. Then the resultant structure is called perianth whose individual units are called tepals.

A. Thalamus is the swollen end of the peduncle that bears flowers.
B. Pedicel connects individual flower to the inflorescence.
C. The perianth is the non-essential floral whorl without differentiation of calyx and corolla.
D. Lodicules are the scaly structure below ovary in grasses.
Hence, the correct answer is 'Perianth' 

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Colour of Bougainvillea flower is due to colour of its ________.

  1. Corolla

  2. Bracts

  3. Calyx

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

The flowers of Bougainvillea are bright pink in colour because of the colour of the bracts. These flowers do not have a distinct and differentiated corolla as well as calyx. Three tiny flowers are surrounded by the bracts. These bracts are modified leaves. They protect the flower and attract the pollinators.

Hence, the correct answer is 'Bracts'

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Identify the wrong statement.

  1. A plant that bears male, female and bisexual flowers is polygamous

  2. Actinomorphic flower can be dissected into two equal halves from any place

  3. Superior ovary is found in hypogynous flowers

  4. Side of the flower towards the bract is called posterior side
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When the flowers are laterally borne, then the side of the flower towards the apex of central axis or mother axis is considered to be the posterior side in a floral diagram while the side opposite to the posterior side is towards bracts and is called the anterior side. So, side of the flower towards the bract is called the anterior side.

Hence, the correct answer is 'Side of the flower towards the bract is called posterior side'

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Perianth refers to

  1. Nonessential floral organs

  2. Essential floral organs

  3. Fused stamens and carpels

  4. Undifferentiated calyx and corolla
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When the calyx and corolla are indistinct and undifferentiated, the resultant whorl is called the perianth. 

A. Accessory whorls of calyx, corolla and perianth are non-essential floral organs as they are not directly involved in the process of fertilization.
B. Androecium and gynoecium are considered to be essential floral organs because they form the male and female gametes respectively.
C. Fused stamens with style and stigma of carpel form gynostegium.
D. Undifferentiated calyx and corolla are called perianth.
Hence, the correct answer is 'Perianth'.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Structure equivalent to perianth is

  1. Superior palea

  2. Inferior palea

  3. Glumes

  4. Lodicules
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The term perianth is used to refer to the condition when the calyx and corolla are not differentiated. In grasses, the similar condition is seen by the presence of lodicules, that are situated below the ovary. 

A. & B. Palea are bracts present in spikelets of the grasses.
C. Glumes are the involucre in the inflorescence of a spike.
D. Lodicules are the covering present below the ovary, similar to the perianth.
Hence, the correct answer is 'Lodicules'

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Individual components of perianth are called ______.

  1. Sepals

  2. Petals

  3. Tepals

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

The whorl perianth represents undifferentiated calyx and corolla. Its individual units are called tepals. Tepals can be petaloid if coloured bright or sepaloid if green.

A. Sepals are the units of the calyx.
B. Petals are the units of the corolla.
C. Tepals are the units of perianth.
D. Bracts form a cover exterior to the calyx.
Hence, the correct answer is 'Tepals'.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Achalmydeous flower occurs in

  1. Sunflower

  2. Betel

  3. Onion

  4. <p>Avena</p>
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Achlamydeous condition refers to the absence of both the calyx and the corolla. Instead, there is a presence of the whorl called perianth. This type of condition is seen in betel, belonging to the family Piperaceae.

A. Sunflower shows calyx as pappus and corolla.
B. Betel is achlamydeous.
C. Onion has perianth arranged in two whorls.
D. Avena has the lemma and palea.
Hence, the correct answer is 'Betel'.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Involucre is composed of

  1. Bracts

  2. Extra calyx

  3. Bracteoles

  4. Scale leaves
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Involucre refers to the group of bracts that are arranged in one or more whorls around the flowers. Example, sunflower.

A. Bracts make up the involucre.
B. Epicalyx makes up the extra calyx, present exterior to the calyx, example, Cotton.
C. Bracteoles make up the epicalyx.
D. Scale leaves make up the scaly bracts at the base of each floret in family Asteraceae.
Hence, the correct answer is 'Bracts'

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Read the statements carefully :
a) Flowers are morphological and embryological marvel and the site of sexual reproduction
b) The proximal end of the filament is attached to the thalamus or the petal of the flower
c) The number and length of stamens are variable in flowers of different species
d) stamen attached to the petal is epipetalous
How many above statements are correct

  1. One

  2. Two

  3. Three

  4. Four
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Flowers are the site of sexual reproduction in a flowering plant. They are a morphological and embryological marvel. The proximal end of the filament of the stamen is attached to the thalamus or the petal of the flower. The number and length of stamens are variable in flowers of different species. The number varies from 3 to 10 in different species. Also, the size of stamens varies largely in different species. Stamen attached to the petal is called as epipetalous. For example, Brinjal.

Thus, the correct answer is option D.

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Bougainvillea flower is an example of

  1. incomplete flower

  2. having a large nectary

  3. water pollination

  4. large colorful bracts
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Bougainvillea flower of the plant is generally white and in which each cluster of 3 flowers is surrounded by 3 or 6 bracts with the bright colors associated with the plant, including purple, magenta, red, pink, white, or yellow, orange,

So, the correct answer is 'large colorful bracts'

Multiple choice biology the flower structure of a bisexual flower growth and development in plants basics of leaf and flower

Perianth is bilabiate personate is

  1. Antirrhinum

  2. Salvia

  3. Peristrophe

  4. Ocimum
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Antirrhinum is a genus of plants commonly known as dragon flowers or snapdragons because of the group (Saerorhinum). The genus is characterized by personate flowers with an inferior gibbous corolla. Cultivars have showy white, crimson, or yellow bilabiate flowers Corolla is blipped. The two lips may be open (Bilabiate and Ringent, e.g., Salvia) or closed (Bilabiate and Personate, e.g., Antirrhinum). The mouth is closed by a projection of the lower lip called palate.
So the correct answer is 'Antirrhinum'.