Equilibrium, by definition, is a situation or condition wherein all forces that act upon an object are balanced. This follows the condition that rightward forces are balanced by the leftward forces and the upwards forces are balanced by the downward forces, but does not necessarily mean that they should equate each other. Balanced is the keyword that is utilized to describe equilibrium conditions or situations.
Answer:
The correct answer would be D.Alveolar sacs are surrounded by thin capillaries where gases can be exchanged.
Alveoli are tiny sacs which form the site of gas exchange in the lungs.
The features of alveoli which help in gas exchange are:
- They increase the surface area in the lungs thus, more space is available for gas exchange.
- They have very thin walls, as thin as the thickness of a single cell only.
- They are surrounded by a bunch of thin capillaries which exchange gases with alveoli.
Answer:
Stomata are the organs present on the stem and leaves of the plant and help in the gaseous exchange and evaporating water present in the aerial parts of the plant. Mainly leaves stomata plays role in gaseous exchange and transpiration which is the evaporation of the aerial water of plants by opening and closing the stomata. Stomata are small pores mostly and normally present under the leaves and regulated by the guard cells, dum bell shaped cells to close or close it.
Other than closing and opening the stomata, stomata density also can affect the rate of gas exchange as well as transpiration. Stomata density is the presence of the numbers of the stomata per unit area. In heat or sunny area the stomata density is higher than the shady or dark area to increase the transpiration in order to cool down the leaves of the plant which prevent the chloroplast proteins to denature.