When we talk about evolution we come across the process of natural selection. Genetic variation is always required for the natural selection. A change or variation in the genes may help the individuals in a population to better adapt to the environment. Such changes may be brought by mutations or random mating in the population. Such variations help in the survival of the population by allowing them to adapt to changing environmental conditions.
The process of the development of reproductive cells in males is called Spermatogenesis. Spermatogenesis develops immature germ cells into mature sperm cells. Oogenesis is the process of the development of reproductive cells in females. Fertilization happens when the sperm and egg cells unite.
The correct answer is 'If molecules are small enough, then they can pass through the semipermeable membrane because they can cross the semipermeable membrane from their small pores or openings'.
The semipermeable membrane is permeable to few molecules, and the smaller molecules pass through the molecules from small pores present in the semipermeable membrane. The size of the big molecules are large, so, they cannot cross through semipermeable membrane.
Synchroniser switch is in the "on" position.
The phrase that best describe the word "energy" is letter "C. the ability to do work". The unit most commonly used to express energy is Joules (J) which is also derived from the equation of work which is the product of force and the distance that a body moves parallel to the force applied.