Biology

Plant Transport and Physiology

2,012 Questions

Access a comprehensive set of questions on plant transport mechanisms and physiological adaptations. Topics include water movement, translocation of food, and plant responses to external stimuli. These biology questions are essential for medical entrance exams and other science competitive tests.

Xylem and phloem transportTranspiration and evaporationPlant adaptationsGeotropic and phototropic responsesWater absorption by rootsRespiration in roots

Plant Transport and Physiology Questions

Multiple choice

Stomata is found in?

  1. nonvascular plants

  2. vascular plants

  3. neither

  4. both non and vascular plants
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Stomata are specialized pores found in the epidermis of leaves and stems of vascular plants, allowing for gas exchange.

Multiple choice

Vascular tissues are important for the?

  1. diffusion of water

  2. absorption of energy

  3. transport of materials

  4. opening of stomata
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Vascular tissues, specifically xylem and phloem, are responsible for the transport of water, minerals, and nutrients throughout the plant.

Multiple choice

What pushes water and minerals up the plant?

  1. root motor

  2. root pressure

  3. gravity

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

Root pressure is one of the mechanisms that helps push water and dissolved minerals upward from the roots through the xylem.

Multiple choice

Water is transported from a plant's roots to its leaves in a tissue called?

  1. muscle

  2. xylem

  3. veins

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

Xylem is the specialized vascular tissue responsible for transporting water and dissolved minerals from the roots upward to the rest of the plant. Muscle and arteries are animal tissues, while veins in plants are bundles of vascular tissue but not the name of the tissue itself.

Multiple choice

Openings that let air and water move it and out of leaves are called?

  1. stomach

  2. stomata

  3. las bocas

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

Stomata are tiny pores, typically found on the underside of leaves, that facilitate gas exchange (carbon dioxide and oxygen) and the release of water vapor through transpiration. Stomach and las bocas are incorrect terms in this biological context.

Multiple choice botany stem - external morphology morphology of the stem stem shoot system in plants

In a hollow stem, what is most affected?

  1. Conduction of food

  2. Conduction of water

  3. Storage of food

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Hollow stem is characterized by the disintegration of pith leaving the central space empty which is otherwise occupied by pith. The disintegration of pith is caused by rapid elongation and radial expansion of growing stem. Translocation of organic nutrient and water is the function of phloem and xylem respectively and hence, the disintegration of pith does not affect these functions. Pith serves to store and transport the nutrient while the hollow stem contains water, storage of food is most affected in hollow stem. 
Thus, the correct answer is option C.
Multiple choice botany stem - external morphology morphology of the stem stem shoot system in plants

Function of stem is

  1. Bear leaves and branches

  2. Conduction of water & minerals

  3. Conduction and storage of food

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The main functions of stems are as follows,

  • The stems bears branches and leaves and also gives place from where flowers and fruits grow.
  • Conduction of fluids and minerals between the roots and the shoots in the xylem and phloem.
  • Storage of food.
  • Stems have meristems that generate new living tissue.
    Thus, the correct answer is option D.

Multiple choice botany stem - external morphology morphology of the stem stem shoot system in plants

Stems have played and important role in plant evolution. Their functions have changed and evolved over a period of time. From the list given below (i to iv), identify the functions performed by stems in different types of plants.
(i) Photosynthesis
(ii) Support
(iii) Storage
(iv) Spread and dispersal of plants

  1. (i) and (ii) only

  2. (i), (ii) and (iii) only

  3. (i), (ii), (iii) and (iv)

  4. (ii), (iii) and (iv) only
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In some plants, the stem has been modified to perform different functions. These are the adaptations shown by the plants due to adaptation and evolution. 

In dessert plants, the stem become green and flat to perform photosynthesis. 
In climbers, the stem tendrils cling or wound on the other plants to provide support. 
In rhizome and tubers, the food is stored in the stem. 
In plants like runners which spread on the land, the seeds or the spores are dispersed. This helps in the dispersed growth of the plants. 
Thus, the correct answer is option C. 

Multiple choice botany stem - external morphology morphology of the stem stem shoot system in plants

Plants belonging to family Cactaceae  stores water in stems. It means, they are 

  1. Ephemerals

  2. Drought resistants

  3. Annuals

  4. Non-succulents
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cactaceae have many adaptations that make them drought resistant in dry areas. They have a thick and hard-walled stem that helps in water storage. The stems of Cactaceae are fleshy and photosynthetic. A thick and waxy coating of it helps the cactus from evaporating excess water. Instead of leaves, most of them have spines or scales which are modified leaves. These spines and scales do not lose water through evaporation and protect the cactus from herbivores.

So, the correct answer is 'Drought resistants'

Multiple choice biology plant nutrition limiting factors factors affecting photosynthesis photosynthesis in higher plants

Blackman's law was conceived in connection with

  1. Photosynthesis

  2. Respiration

  3. Transpiration

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

In the twentieth century, Blackman (1905) proposed his principle of limiting factors. According to this principle, the rate of photosynthesis controlled by several factors is only as rapid as the slowest factor permits. He claimed that, if all other factors are kept constant the factor under consideration will affect the rate of photosynthesis, starting at a minimum below which no photosynthesis takes place and ending with an optimum at which a horizontal would be established, that is, the rate would remain constant despite further increases in that factor. At this point some other factor becomes limiting.

So, the correct option is 'Photosynthesis'.

Multiple choice biology plant nutrition limiting factors factors affecting photosynthesis photosynthesis in higher plants

Blackman's law of limiting factor is applied to ...........

  1. Respiration

  2. Transpiration

  3. Photorespiration

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

Law of Limiting factor was given by Blackman This law governs the rate of photosynthesis According to this law, the process of photosynthesis is controlled by many factors but the rate of photosynthesis will depend on the factor which is present in limited quantity.

For example, photosynthesis depends upon carbon dioxide concentration, light intensity, water, presence of chlorophyll. If all factors are present but light intensity is low then light will become the limiting factor and rate of photosynthesis will depend only on light, the limiting factor. Hence option D is correct.