Which of the following is correct:
(a) Cells of all living organisms have a nucleus.
(b) Both animal and plant cells have a well defined cell wall.
(c) In prokaryotes, there are no membrane bound organelles.
(d) Cells are formed de novo from abiotic materials.

Which of the following cells do not have nucleus?

Which one of the following living organisms completely lacks a cell wall?

Which of the following is not correct ? Virchow explained that cells ae formed from pre existing cells

Which among the following are the smallest living known without a definite cell wall, pathogenic to plants as well as animals and can survive without oxygen ?

Which of the following is not correct? (a) Robert Brown discovered the cell. (b) Schleiden and Schwann formulated the cell theory. (c) Virchow explained that cells are formed from pre-existing cells. (d) A unicellular organism carries out its life activities within a single cell.

Which of the following cell organells is responsible for extracting energy from carbohydrates to form ATP ?

A glass full of hot milk is poured on the table. It begins to cool gradually. Which of the following is correct? (a) The rate of cooling is constant till milk attains the temperature of the surrounding. (b) The temperature of milk faills off exponentially with time. ( c) While cooling, there is a flow of heat from milk to the surrounding as well as from surrounding to the milk but the net flow of heat is from milk to the surrounding and that is why it cools. (d) All three phenomenon, conduction, convection and radiation are responsible for the loss of heat from milk to the surroundings.

New cells generate from (a) bacterial fermentation (b) regeneration of old cells (c) pre-existing cells (d) abiotic materials