Questions Related to botany

Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

Phase contrast microscope is 

  1. Based on the scattering of light and using a dark field condenser.

  2. Used for the study of living cells.

  3. Related to retardation and thickness of object.

  4. The best method for studying non-living ultra structure.

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Phase contrast microscopy is particularly important in biology. It reveals many cellular structures that are not visible with a simpler bright field microscope. These structures were made visible to earlier microscopists by staining, but this required additional preparation and killed the cells. The phase contrast microscope made it possible for biologists to study living cells and how they proliferate through cell division. After its invention in the early 1930s, phase contrast microscopy proved to be such an advancement in microscopy, that its inventor Frits Zernike was awarded the Nobel prize in 1953.

Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

A fluorescent microscope is used

  1. For increasing resolving power.

  2. For obtaining X-ray diffraction pattern of DNA.

  3. To study cell and their components in a living state.

  4. To localise cell structure stained with fluorochrome dyes.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A fluorescence microscope is an optical microscope that uses fluorescence and phosphorescence instead of or in addition to, reflection and absorption to study properties of organic or inorganic substances. The "fluorescence microscope" refers to any microscope that uses fluorescence to generate an image, whether it is a more simple set up like an epifluorescence microscope or a more complicated design such as a confocal microscope, which uses optical sectioning to get better resolution of the fluorescent image. So, fluorescent microscope is used to localise cell structure stained with fluorochrome dyes and not for increasing resolving power, for obtaining X-ray diffraction pattern of DNA and to study cell and their components in a living state. 

Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

Light microscopes

  1. Work by reflecting electrons off the surface of an object being studied

  2. Can generally magnify objects about 10,000 times without blurring

  3. Use light and glass lenses to magnify an image

  4. Provides more resolution than an electron microscope

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The microscope is the instrument used to magnify the image of an object that we cannot see by our naked eyes. It is of two types on the basis of a number of lenses, simple microscope, and compound microscope. A light microscope is a compound microscope that uses focused light and two lenses to magnify a specimen.

Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

If a microscope has a $10\times$ objective lens and $10\times$ ocular lens, it would magnify the object by 

  1. $10\times$
  2. $20\times$
  3. $50\times$
  4. $100\times$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The compound microscope is the instrument used to magnify the image of the object that we cannot see by naked eyes. It uses two lenses or lens systems, one is the objective lens which enlarged the image of the object and the second is an ocular lens which magnifies the image formed by the first. The total magnification is the product of the magnifications of two lens systems. Hence, the microscope which has a 10X objective lens and 10X ocular lens, it would magnify the object by 10 × 10 = 100 times. 

Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

The strength of magnification of oil immersion lens is

  1. $20\times$
  2. $500\times$
  3. $1000\times$
  4. $100\times$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
There are three types of objective lens: 10X (low power objective lens); 40X (high power objective lens) and 100X (oil immersion objective lens). Each objective lens is represented by a particular colour. Oil immersion is the technique used to increase the resolving power of the microscope. In this technique, oil is used to avoid the different refractive index of air and glass which affect the numerical aperture.
Multiple choice botany cell and cellular organization cell theory microscope cell and its discovery

Anton van Leeuwenhoek was from

  1. France

  2. Holland

  3. Sweden

  4. Britian

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Antonie Philips van Leeuwenhoek was a Dutch businessman and scientist. He belonged to Holland. He discovered protozoa, a single-celled organisms. He named it as animalcules. He also had contributed in the improvement of the microscope and laid foundation for microbiology. 

Thus, the correct answer is 'Holland.'

Multiple choice botany kingdom plantae classification of bryophytes types of bryophytes bryophyta

The female sex organs in Riccia and Funaria is

  1. Antheridium

  2. Paraphyses and capsule

  3. Archegonium

  4. All of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In Bryophytes, archegonium is the female sex organ. The female shoot arise from the base of the male shoot and called as archegonial branch or archegoniophore. The apex of female shoot is called female receptacle from which cluster of archegonia arise intermixed with non- capitate paraphysis. 

Each archegonium has a stalk, flask-shaped venter and a neck. Venter encloses a basal egg cell (oosphere) and upper smaller venter canal cell. Neck consists of 6 or more neck canal cells (6-11).

Multiple choice botany pictorial feature of plant kingdom classification of bryophytes types of bryophytes bryophyta

Which of the following statements is true about bryophytes?

  1. The sporophyte is dependent on gametophyte for support, shelter and nutrition

  2. The sporophyte is haploid

  3. The gametophyte is diploid

  4. The gametophyte is dependent on sporophyte for support, shelte and nutrition

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bryophytes are gametophyte dominant, meaning that the more prominent, longer-lived plant is the haploid gametophyte. The diploid sporophytes appear only occasionally and remain attached to and nutritionally dependent on the gametophyte.

So, the correct answer is A. (The sporophyte is dependent on gametophyte for support,shelter and nutrition)

Multiple choice botany pictorial feature of plant kingdom classification of bryophytes types of bryophytes bryophyta

Moss plants develop from

  1. Oospores

  2. Protonema

  3. Antherozoids

  4. Diploid spores

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the life cycle of mosses, haploid spores germinate to produce a filamentous, creeping, green, and branched structure called a protonema. The leafy gametophyte, which represents the mature moss plant, then develops as a lateral bud from this protonema stage.

Multiple choice botany kingdom plantae classification of bryophytes types of bryophytes bryophyta

Plant body of liverworts is

  1. Thalloid in Porella

  2. Thalloid in Marchantia

  3. Leafy in Marchantia

  4. More than one option is correct

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Liverworts can have diverse plant bodies; some like Marchantia are thalloid, while others like Porella are leafy. Thus, stating Marchantia is thalloid is correct, but claiming it is the exclusive thalloid form or that Marchantia is leafy is incorrect, making the 'more than one' option a distractor since specific statements can vary, but Marchantia specifically has a thalloid body.