Biology Questions

23 chromosomes are in a human gamete.

Human somatic cells have 46 chromosomes(23 pairs) but a gamete(germ cell) gets half the amount, i.e. 23 chromosomes, (one from each pair). There will be half the number of chromosomes an organism has in its somatic cells (all other body cells except gametes).

For example in humans, the somatic cells contain 46 chromosomes which are the diploid number (2n) and each sperm and egg has 23 chromosomes where one of them is the sex chromosome.

Scientists estimate the volume of blood in a human body to be approximately 7 percent of body weight. An average adult body with a weight of 150 to 180 pounds will contain approximately 4.7 to 5.5 liters of blood. An average child with a body weight of 80 pounds will have approximately half the amount of blood as an adult.

The amount of blood in a human body varies, depending on factors such as age, sex, overall health and even where a person lives. For example, men tend to have more blood than women of comparable size and weight.

Interestingly, people who live at high altitudes may have up to two liters of extra blood compared to those who live at lower altitudes. Because the air at higher altitudes has less oxygen, people who live at high altitudes need extra blood to deliver the right amount of oxygen to their lungs.

We know that 1 Pint = 0.473 liters

Hence, an average amount of blood in the human body = 4.7 - 5.5 lit = 10 - 12 pints.

S-phase (synthesis phase) is the part of the cell cycle in which DNA is replicated, occurring between G1 phase and G2 phase. Precise and accurate DNA replication is necessary to prevent genetic abnormalities which often lead to cell death or disease.

Trypanasoma is a protozoan animal. It lives as a parasite in the blood and later invades the cerebrospinal fluid to cause the sleeping sickness. This parasite is transmitted by the Tsetse fly.

Electrons are stripped from water in the light reactions of photosynthesis. Light provides the energy to excite electrons.

ATP and NADPH are both products of the light reactions and are used to power the Calvin cycle.

Mumps : This is a swelling caused by information of parotid glands placed in front of our ear region. The inflammation is caused by a virus.