Microorganisms such as bacteria can be removed by disinfection. Certauns substances called biocides are addes to water to make it pure. Purification can also be done by UV-light .
Answer:
The correct answer will be option-B
Explanation:
Meiosis is a way of cell division used by the organism to produce a large number of cells from a few parent cells. This is used to make the gametes of the body.
Meiosis produces four daughter cells from a single parent cell in two stages that is meiosis I and II. Each stage proceeds in four phases- prophase, metaphase, anaphase and telophase.
The reduction division of the chromosomes or the ploidy number takes place during anaphase I of meiosis I and not prophase I which is the initial phase of the division. Therefore, during prophase I the chromosome number of the cell remains the same.
Thus, Option-B is the correct answer.
Answer:
The suprachiasmatic nuclei enable the nervous system to respond to daily light/dark alterations through their stimulation of melatonin.
Explanation:
Melatonin is a hormone produced naturally by the body. Its function is to regulate the body's circadian cycle. This hormone is stimulated and begins to act by changing between a light environment and a dark environment. This stimulation interacts with the suprachiasmatic nuclei making the nervous system understand this change and luminosity of the environment and respond to the action of melatonin.
The answer is the first one ( True )
