Biology · Science General

Cell Biology and Structure

3,062 Questions

Cell biology focuses on the structure and function of cellular organelles. Key topics include cellular respiration, DNA inheritance, and energy production. These fundamental biology concepts are crucial for medical entrance and state service examinations.

Cell organelles functionsCellular respiration sitesDNA and ribosomesAnimal cell structurePlant cell components

Cell Biology and Structure Questions

Multiple choice biology cell-the basic unit of life nucleus organelles in cell membranous and non-membranous organells

Which of these is not found in the nucleus?

  1. Nucleoplasm instead of cytoplasm

  2. Functioning ribosomes

  3. Chromatin that condenses to chromosomes

  4. Nucleolus that produces rRNA
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Ribosomes are synthesized in the nucleolus but function in the cytoplasm. Therefore, functioning ribosomes are not found within the nucleus.

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Cellular totipotency is demonstrated by

  1. Only gymnosperm cells

  2. All plant cells

  3. All eukaryotic cells

  4. Only bacterial cells
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Totipotency is the ability of a single cell to divide and produce all of the differentiated cells in an organism. Many somatic plant cells, including some fully differentiated types (e.g., leaf mesophyll), provided they contain intact nuclear, plastid and mitochondrial genomes, have the capacity to regenerate into whole plants. This phenomenon is totipotency.

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Rapidly dividing unorganised mass of cells in tissue culture is

  1. Callose.

  2. Callus.

  3. Embryoid.

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

Tissue culture is a growth of cells or tissues separate from the organism in an artificial environment. The process is called as micropropagation in plant tissue culture. In tissue culture, the small piece of plant or animal is used to grow complete individual and those small parts are called as explants whereas complete grown individuals are called clones. The explant initially turns into rapidly dividing unorganised mass of cells on solid or liquid culture and that is called a callus. 

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Cellular totipotency means

  1. Synthesis of new cells.

  2. Formation of new species.

  3. Formation of new plants.

  4. Capability of plant cell to form complete plant.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Cellular totipotency means the ability of a cell to give rise to complete individual i.e., the formation of the complete cellular organisation from a single cell. Plant cells are totipotent as they can give rise to complete plant. So answer D is correct.

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Callus is

  1. Tissue that forms embryo

  2. An insoluble carbohydrate

  3. Tissue that grows to form embryoid

  4. Unorganised actively dividing mass of cells maintained in culture
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Callus is unorganized actively dividing the mass of cells maintained in culture. It has a meristematic cell which has ample amount of cytoplasm to trigger cell division. It is treated with the growth hormones to allow the cell division and differentiation. Callus when treated with auxin it promotes rooting and when it is treated with cytokinin it stimulates cell maturation, differentiation and finally, promotes the development of stem.

So, the correct answer is option D.

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Callus is _____________.

  1. Tissue that forms embryo

  2. An insoluble carbohydrate

  3. Tissue that grows to from embryoid

  4. Unorganised actively dividing mass of cells maintained in culture
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Callus is defined in plant tissue culture as an unorganized, proliferating mass of parenchyma cells that arises from an explant. It is typically maintained on a culture medium containing specific hormones.

Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

A totipotent cell means ________________.

  1. An undifferentiated cell capable of developing into a system or entire plant

  2. An undifferentiated cell capable of developing into an organ

  3. An undifferentiated cell capable of developing into complete embryo

  4. Cell which lacks the capability to differentiate into an organ or system.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A totipotent cell means an undifferentiated cell capable of developing into a system or entire plant.
Multiple choice botany tissue culture common modes of vegetative propagation plant breeding for food production plant tissue culture

Agitation during tissue culture serves for

  1. Aeration of the culture

  2. Constant Mixing

  3. Breakage of cell aggregates in small particles

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

Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition. Plant tissue culture is widely used to produce clones of a plant in a method known as micropropagation. Agitation during tissue culture serves for:

  • Aeration of the culture
  • Constant Mixing
  • Breakage of cell aggregates in small particles

Multiple choice evs we are special defects of eye disorders of nervous system braille script

Braille cells are

  1. made up of six dots that fit under the fingertips, arranged in two columns of three dots each.

  2. made up of ten dots that fit under the fingertips, arranged in two columns of five dots each.

  3. made up of fourteen dots that fit under the fingertips, arranged in two columns of seven dots each.

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Braille was named after the creator, Louis Braille, a Frenchman who lost his sight as a result of a childhood accident. It involves the usage of 6 dots and the direction is left to right. The paper used is thought as a file folder or index card for proper sensing by the visually impaired people. The characters have rectangular blocks called cells that have tiny bumps called raised dots. The cells are arranged in two columns of three dots each.
So, the correct answer 'made up of six dots that fit under the fingertips, arranged in two columns of three dots each'.
Multiple choice botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

Chromonemata are embedded in a

  1. Stroma

  2. Matrix

  3. Sugar

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

Chromonemata are embedded in the matrix. Chromonemata are the spirally coiled central filament of a chromatid along which the chromomeres are aligned. A chromomere is one of the serially aligned beads or granules of a eukaryotic chromosome, resulting from local coiling of a continuous DNA thread. It is visible on a chromosome during the prophase of meiosis and mitosis. 

So, the correct answer is option B.

Multiple choice botany the mitotic cell cycle chromosome and its structure chromosome nucleus and chromosome

Nucleus contains ________ which are rod shaped structures.

  1. Cytoplasm

  2. Chromosomes

  3. Chromatin

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

Chromosomes are thread like structures located inside the nucleus of animal and plant cells. Each chromosome is made of deoxyribonucleic acid (DNA). Passed from parents to offspring, DNA contains the specific instructions that make each type of living creature unique.