Answer:
Explanition:
The immune system is made up of special organs, cells and chemicals that fight infection (microbes). The main parts of the immune system are: white blood cells, antibodies, the complement system, the lymphatic system, the spleen, the thymus, and the bone marrow.
The correct answer is: d) begins later in life
Eggs or female reproductive cells are formed well before birth in a huge number (primordial oocytes). But, the number of oocyte decreases after birth constantly (there are 2 million oocytes at birth and 40,000 of them in puberty). At menopause, no egg cells are left.
On the other hand, the first sperms are formed only from puberty, but the production of those cells never stops.
Answer:
Oxygen is a colourless, odourless, tasteless gas essential to living organisms, being taken up by animals, which convert it to carbon dioxide; plants, in turn, utilize carbon dioxide as a source of carbon and return the oxygen to the atmosphere.
Answer:
Perception
Explanation:
Perception is usually defined as a collective process of accumulation, selection and interpretation, and organization of the sensory information. In simple words, it helps in the collection of information that is transferred from the different sense organs and interpreted by the brain. This collected information is used in understanding and interacting with the environment.
Thus, perception refers to the use of sense organs such as the nose, ear, eyes and making a person able to smell, hear and see things.