Tag: botany

Quizzes (264) Questions (5276)

Questions Related to botany

Multiple choice botany living world of plants - plant physiology historical events in photosynthesis history of photosynthesis introduction to photosynthesis

Scientist who discovered the role of light in photosynthesis was

  1. Sachs

  2. Jan Ingenhousz

  3. Senebier

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

Joseph Priestley discovered that plants produce oxygen.
Jean Senebier discovered that the source of this carbon is carbon dioxide. 
Sachs discovered that starch grains are produced in plant leaves and  these are the first visible product of the process of photosynthesis. 
Jan Ingenhousz discovered that light plays a major role in photosynthesis. 

Thus, the correct answer is option B.

Multiple choice botany living world of plants - plant physiology historical events in photosynthesis history of photosynthesis introduction to photosynthesis

Most of the experimental work in photosynthesis has been done on 

  1. Chlamydomonas

  2. Chlorella

  3. Hydrilla

  4. Spinach leaf
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Most of the experimental work in photosynthesis has been done on Chlorella. Through photosynthesis it multiplies rapidly, requiring only carbon dioxide, water, sunlight and a small number of minerals to reproduce. 
  • It is easy to culture and it is easy to understand the photosynthetic process in chlorella cells.
  •  Based on the above advantages most of the photosynthetic work was conducted in chlorella compared to hydrilla, spinach leaves, and Chlamydomonas. 
Multiple choice botany living world of plants - plant physiology historical events in photosynthesis history of photosynthesis introduction to photosynthesis

Chloroplast involvement in photosynthesis was discovered by

  1. Julius von Sachs

  2. Mayer

  3. Ingenhousz

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

The correcr answer is ' Sachs ' . Sachs stated that green parts in the plants produces glucose which is later stored as starch and this starch is the first visible product of photosynthesis . in 1865 Sachs proved that chlorophyll was confined to special bodies only , which was later termed as Chloroplasts .

Multiple choice botany living world of plants - plant physiology historical events in photosynthesis history of photosynthesis introduction to photosynthesis

Van Helmont concluded that plants get their food from

  1. Air

  2. Water

  3. Humus
  4. Air and ${H _2 O}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Van Helmont concluded that plants get their food from water. Van Helmont wanted to prove plants use materials from the soil to perform photosynthesis and done an experiment and proved that.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

During isolation of genetic material, the chemical used to precipitate out the purified DNA is

  1. Bromophenol blue

  2. Chilled ethanol

  3. Ethidium bromide

  4. Both A and C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The purified DNA, after treatment with various enzymes, precipitates out after addition of chilled ethanol. This is viewed as a collection of fine threads in the suspension, and is easily collected. The process is known as DNA spooling.
So, the correct answer is 'Chilled ethanol'.
Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

Select the incorrect Statement regarding DNA replication with respect to the template strand

  1. Leading strand is formed in 5 $\rightarrow$ 3 direction.
  2. Okazaki fragments are formed in 5 $\rightarrow$ 3 direction.
  3. DNA polymerase catalyses polymerisation in 5 $\rightarrow$ 3 direction.
  4. DNA polymerase catalyses palymerisation in 3 $\rightarrow$ 5 direction.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since DNA polymerase requires a free 3' OH group for initiation of synthesis, it can synthesize in only one direction by extending the 3' end of the preexisting nucleotide chain. Hence, DNA polymerasemoves along the template strand in a 3'–5' direction, and the daughter strand is formed in a 5'–3' direction.

So, the correct answer is 'DNA polymerase catalyses polymerisation in 5 
→→ 3 direction'

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

The sequence of strategies involved in the isolation of a gene of interest from a plant cell during the process of rDNA technology

  1. Dissolution of biological membrane

  2. Enzymatic digestion of cell wall

  3. Precipitation of DNA

  4. Removal of DNA by spoiling
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Isolation of the Genetic Material (DNA):

Nucleic acid is the genetic material, which is present in all living organisms. In majority of organisms, this is present in the form of deoxy-ribonucleic acid (DNA). DNA must be present into pure form, i.e., free from other macro-molecules (like proteins, RNA, enzymes, etc.) in order to cut the DNA with restrictor enzymes.

Isolation of genetic material (DNA) is carried out in the following steps:

(a) Since the DNA is enclosed within the membranes, so, in order to release DNA along with other macro-molecules such as proteins, polysaccharides and lipids, bacterial cells/plant or animal tissues are treated with the enzyme lysozyme (bacteria), cellulose (plant cells), chitinase (fungus), respectively.

(b) RNA can be removed by the treatment with ribonuclease, whereas proteins can be removed by the treatment with protease.

(c) Other molecules can be removed by appropriate treatments and ultimately purified DNA will precipitate out, after the addition of chilled ethanol. This can be seen as collection of fine threads in the suspension.

So, the correct answer is “Precipitation of DNA”.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

During the process of isolation of DNA, chilled ethanol is added to

  1. Break open the cell to release DNA

  2. Facilitate action of restriction enzymes

  3. Remove proteins such as histones

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

Chilled ethanol is used in DNA isolation because DNA is insoluble in ethanol, causing it to precipitate out of the solution as fine threads.

Multiple choice botany biotechnology: principles and processes manipulation of dna electrophoresis isolation and separation of dna

Insect-resistant transgenic cotton has been produced by inserting a piece of DNA from.

  1. An insect

  2. A bacterium

  3. A wild relative of cotton

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

Insect-resistant transgenic cotton, commonly known as Bt cotton, is created by inserting crystal protein genes (cry genes) derived from the soil bacterium Bacillus thuringiensis into the cotton genome.