A. external
These types of signals are observed when there is a cut on the body. The epidermal cells lose contact with one another and divide faster until they are in contact once again. After they come into contact, division slows down again.
Diffraction occurs when a wave moves through an opening in a barrier. This causes the wave to change direction and spread out.
Waves can behave in three different ways depending on the obstacles they encounter. They can reflect, refract or diffract. In diffraction, waves such as sound, light or water either bend around small objects that obstruct their passage or spread out as they travel through a gap in the barrier.
The degree of diffraction forms a direct relationship with wavelength. It generally increases as wavelength increases. Conversely, the amount of bending lessens as wavelength decreases. However, if the opening of the barrier is smaller than the wavelength, the effect of diffraction is not easily observed. Hope this helps.
Answer: In females, most of gametogenesis occurs during embryonic development. Primordial germ cells migrate into the ovaries at week 4 of development and differentiate into oogonia (46,2N).
Explanation:
Movement is the main function of muscular tissue. They have the ability to contract and this is what brings about the movement of body parts. They also help to maintain body posture and position.
