Correct Answer:
(C) Viroids consist of single-stranded RNA molecules
Prions are a smallest proteinaceous infectious particle. Mycoplasma is a genus of bacteria that lack a cell wall around their cell membrane. Viroids are the smallest infectious pathogens known consisting solely of short strands of circular, single-stranded RNA without protein coats. They are mostly plant pathogens, some of which are of economic importance. Rickettsia is a genus of non-motile, gram- negative, non-spore forming, highly pleomorphic bacteria. They have cell wall.
Ques: 2
Which of the following statements are correct regarding the general difference between plant and animal cells?
Plant cells have cellulose cell walls whilst animal cells do not.
Plant cells do not have plasma membrane unlike animal cells which do.
Mature plant cell has one large vacuole whilst animal cell has many small vacuoles.
Select the correct answer using the code given below:
Correct Answer:
(C) 1 and 3 only
Cell wall is found in the cells of plants, which is made up of cellulose. It provides the cell structural support, protection and a filtering mechanism. Animal cells lack cell wall. Thus, statement 1 is correct. The plasma membrane is a biological membrane that separates the interior of all cells from the outside environment which protects the cell from its environment. Animal cells as well as plant cells have plasma membrane. Hence, statement 2 is incorrect. A vacuole is a membrane - bound cell organelle which are enclosed compartments filled with water containing organic and inorganic molecules. Most mature plant cells have one large vacuole while an animal cell contains several small vacuoles performing various functions. Therefore, statement 3 is correct.
Ques: 3
Which of the following organelle is called ‘Power House’ of the cell?
Correct Answer:
(B) Mitochondria
Animal cells and plant cells both contain cell membrane, cytoplasm, and nucleus. The nucleus has two major functions. It stores the cell’s hereditary material or DNA and it, co-ordinates the cell’s activities within cells. The mitochondrion (plural mitochondria) is a membrane-bound organelle found in most eukaryotic cells. Mitochondria range from 0.5 to 1.0 m in diameter. These structures are sometimes described as 'the powerhouse of the cell' as they generate energy through respiration. During cellular respiration, the initial process takes place in cytoplasm and then in mitochondria.
Ques: 4
Plasma membrane is built up of:
Protein (b) Lipid
Correct Answer:
(D)
The cell membrane (also known as plasma membrane) is a biological membrane that separates the interior of cell from the outside environment. It is composed of two layers of phospholipids and embedded with proteins.
Ques: 5
Which of the following cell organelles play the most significant role in protein synthesis?
Correct Answer:
(B) Endoplasmic reticulum and Ribosome
The rough endoplasmic reticulum (RER) is named as such because its outer membrane is littered with ribosomes. They are responsible for protein synthesis.
Ques: 6
Who is the father of modern genetics?
Correct Answer:
(A) Gregor Johann Mendel
The law of Inheritance was discovered by Gregor Johann Mendel. He is known as the father of modern genetics.
Ques: 7
Mendel's principle of inheritance is based on-
Correct Answer:
(C) Sexual reproduction
Mendel's principle of inheritance is based on sexual reproduction.