Tag: bio-chemistry

Quizzes (82) Questions (1918)

Questions Related to bio-chemistry

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Cells were determined to be the basic structural units of plants and animals, in which of the following time period?

  1. 1600's

  2. 1700's

  3. 1800's

  4. 1900's
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

  • The cell was discovered by Robert Hook in 1665. But the statement that cell is the structural and functional unit of life generalized as cell theory in 1839 by Schleiden and Schwann. Thus, the correct answer is option C.

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Auxospores are formed in the life cycle of diatoms these structure are ________________.

  1. Vegetuative cells with ploidy level N

  2. Asexual spores with ploidy level N

  3. Statosspores with 2N ploidy Level
  4. Sexual spores with ploidy level $2N$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Auxospores are formed by diatoms at an important stage of their life cycle. They are specialized cells which help the diatoms in regaining their normal size. After cell division in diatoms, each daughter cell inherits one of the two valves and hence results in reduction of size of the diatom, to retain the size diatoms produce auxospores and hence they are vegetative.
So, the correct option is, 'Vegetuative cells with ploidy level N'.
Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Which one of the following is incorrect for the members of chrysophyta?

  1. These are nonmotile bivalved organism

  2. Presence of primordial utricle around a central vacuole

  3. Resetve food materials are paramylon and volutin granules

  4. Movement occurs by mucilage propulsion
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Chrysophyta are motile. They sometime produce flagellated motile zoospores during reproduction. They are also bivalved.

Therefore the right answer is "These are nonmotile bivalved organism".

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

The concept ''OMNIS cellula-e-cellala'' means that ,new cells are formed from:

  1. Non living materails

  2. Pre-existing living cells

  3. Dead organic matter

  4. As the results of chemical reaction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

"Omnis cellula e- cellula" means new cells are formed from pre-existing living cells. 

So the correct option is 'pre existing living cells'.

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Which of the following statement is false?

  1. Properties of cellular organelles are present in the molecular constituents of the organelles

  2. Interaction among the molecular components of the organelles results into properties of cell organelles

  3. Biology is the story of life on earth(formation, evolution and biodiversity)

  4. Biology is the life sciences dealing with every aspect of life
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A cell possesses several cellular organelles. Each of the organelle such as mitochondria, endoplasmic reticulum etc. have their own specific function in the cell. These organelles are composed of several molecules and ions such as proteins, lipids, calcium and magnesium ions etc. These molecules together help the organelles perform their specific function. However, when present outside the organelle or in a different organelle the same molecules may perform functions that are different. So, the correct option is 'Properties of cellular organelles are present in the molecular constituents of the organelles'.

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

The size of the cell is not related to the size of the body of an animal.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
The size of cell of an organism has no relation with the size of its body. The size of the cell does not matter. It is always the number of cells. If the organism is unicellular, it is very microscopic. If it is multicellular, as the cell number increases, the size of the organism will also increase. 
Thus, the correct answer is 'True.'
Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Simple one-celled cyanobacteria-like organisms developed on earth.

  1. $5600$ million years
  2. $5000$ million years
  3. $4600$ million years
  4. $3600$ million years
  5. $3000$ million years
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fossil evidence and molecular clocks suggest that simple one-celled prokaryotic organisms, resembling modern cyanobacteria, first evolved on Earth approximately 3.5 to 3.6 billion (3500 to 3600 million) years ago. These early microbes played a crucial role in producing oxygen through photosynthesis, eventually altering Earth's atmosphere.

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

The 'cell doctrine' was given by____________.

  1. Robert Hooke

  2. Schwann, Schleiden and Virchow

  3. Dutrochet

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

Cell theory was proposed by a German botanist, Matthias Schleiden and English zoologist, Theodor Schwann in the year 1839. Cell theory was considered as the most acceptable theory which, elucidated the functioning of a cell. The cell theory includes the following points -
1) All living things are made up of cells.
2) The cell is the smallest living thing that can perform all the functions of life.   
Later on, in the year 1855, Rudolf Virchow added a new point in cell theory that all cells must come from pre-existing cells, which was also known as "Omnis cellula e cellula". The modern cell theory is called as 'Cell Principle' or 'Cell Doctrine'.
So, the correct answer is option B.

Multiple choice bio-chemistry cell-the basic unit of life introduction to cell discovery and cell theory cell discovery cell discovery and cell theory cell as structural and functional unit

Who reported that entity of an organism is not because of the cell but collection of many cells?  

  1. Dutrochet

  2. Dujardin

  3. Robert Brown

  4. Schleiden and Schwann
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Leeuwenhoek was the first to see 'free-living cells' under his microscope. In 1809, Lamarck concluded that all living beings are formed of cells. Living substance was first observed by Corti in 1772 and was named sarcode by Dujardin in 1835. Dutrochet believed in the individuality of cells, i.e., living organisms are made up of a number of individual cells. The nucleus was discovered by Robert Brown and Schleiden and Schwann are credited with the formulation of the cell theory. Thus, the correct answer is option A.