The answer is viruses change their form when the immune system knows how to kill it and thats how they trick the immune system and viruses are much smaller than bacterias
Answer: According to the World Health Organization (WHO), 462 million people face health problems because of under-nutrition and another 1.9 billion people face health problems because of over-nutrition.
Explanation: 462 million adults are underweight around the world according to the World Health Organization (WHO) while 1.9 billion are overweight or obese. Undernutrition, includes 4 sub-forms: wasting, stunting, underweight, and deficiencies in vitamins and minerals. Wasting is low weight-for-height, stunting is low height-for-age and underweight is low weight-for-age. Overweight or obesity is when a person is too heavy for his or her height.
Answer:
The answer is the Severe combined immunodeficiency (SCID).
Explanation:
SCID which is an immune deficiency that is present at birth, is deadly without treatment. Children born with SCID are in constant danger of infections from bacteria, viruses, and fungi. This is because of lack of some essential white blood cells.
The disease however can be essentially cured by a bone-marrow transplant from a related donor, for example, a sibling that is a match in terms of certain immune system proteins.
Explanation:
-infectious
-microscopic
-specific to their host
-can't reproduce on their own (this is why they are not considered alive)
-no organells or membranes. just a protein coat and genetic material
-3 basic shapes: helical , polyhedral , and comples
