Answer: C). Sensory neurons, D).motor neurons
Explanation: Sensory neurons are nerve cells that carry signals from the external parts of the body such as the skin, eyes, ear, nose (the sense organs) to the brain.
Motor neurons are nerve cells that carry information or messages away from the central nervous system ( brain and spinal cord) to the rest of the body such as the skin, muscles and glands.
Answer:
Option 1.
Explanation:
r-selected species may be defined as the species that has higher growth rate, shows less parental care and the rate of survival of the off spring is low as compared with k selected species.
Black widow spiders have the ability to produce 1000 offspring. Their chances of survival are extremely low and only few species of black widow spiders survive. Hence, black widow spider is r-selected species.
Thus, the correct answer is option (1).
Process by which the internal structure of a mineral is altered by the addition or removal of elements. Change in phase (mineral type) and composition are due to the action of chemical agents. Chemical weathering is dependent on available surface for reaction temperature and presence of chemically active fluids.