Which statement best describes the plasma membrane?
(a) it is freely permeable to all substances
(b) it is selectively permeable to certain substances
(c) it is nonpermeable to all substances
(d) more than 1 is correct

Option D

Explanation:

Plasma membrane can be defined as the outer most part of the cell that performs many vital functions for the cell.

It aids in providing structural support to the cell. It prevents the entry of undesirable substances.

Plasma membrane is selectively permeable and it allows the movement of only some particles and molecules which is essential for the cell. It is non permeable as it does not allows the movement of each and every substance.

Hence, the correct answer is option D

label a cell membrane

label b cytoplasm

label c ribosomes

label d dna

the membrane forms the outside of the cell

cytoplasm is the liquid within

ribosomes are the components within that distribute rna

the dna is the genetic make-up

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.