1. Excretion is the process in which all metabolic wastes are passed out of the body. Excretion in humans occurs in several processes through various organs and internal organs of the body.

2. Diffusion is the most common process of excretion in lower organisms. The human body is an extraordinary machine, where various life-processes (respiration, circulation, digestion, etc.) occur simultaneously. As a result, many of the waste products produced in our bodies are in various forms including carbon dioxide, water, and nitrogenous products such as urea, ammonia, and uric acid.

 1. Among these, olive cultivation is studied in olivoculture.

2. Olives originated in the region of Southern Europe near the Mediterranean Sea. Currently, the largest producing countries are in the same region, with Spain, Italy, Morocco, Turkey and Greece being the largest producers.

1. Which plane mirror is used to make periscope?

2. An optical instrument used to see through an object that is occluded from the direct line of sight is called a periscope.

3. A periscope consists of two plane mirrors placed at an angle of 45°.

4. When light falls on one of the mirrors then after reflection from the first mirror it falls on the second mirror which further reflects it and falls on the eye of the observer.

1. Viruses do not find a place in classification because they are not actually considered 'living'.

2. Viruses are non-cellular organisms.

3. The name virus which means poison or poisonous fluid was given by Dmitry Ivanovsky.

4. Viruses cause diseases like mumps, smallpox, shingles and influenza.

1. The average life of red blood cells in the human body is 120 days. This is the time it takes from the formation of red blood cells until they flow in the blood. Red blood cells are made in the bone marrow and then they are shed into the blood. While flowing in the blood, red blood cells carry oxygen from the lungs to the rest of the body and carry carbon dioxide from the rest of the body to the lungs.

1. The largest endocrine gland in the human body is the thyroid gland. This gland is located in the front and bottom of the neck and produces thyroxine and calcitonin hormones.

2. The thyroxine hormone helps regulate the body's metabolism, while the calcitonin hormone helps regulate calcium levels in the blood.

The most important characteristic of evergreen plants is that they always remain green, no matter what the weather. They do not shed their leaves, but replace them with new leaves every year. Evergreen plants thrive well in cold or dry climates, where plants that lose their leaves in winter may die.

Chirmi or Gunja are the seeds of a creeper, which come in two colours, red and white. The color of half of its seeds is red or white and the other half is black. There is also a black-seeded Gunja which is extremely rare.