Epiglottis
The epiglottis is a flap of cartilage the covers the entrance to the throat protecting the lungs from obstruction. It moves when we swallow to allow food in.
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Bacteria are helpful because they produce oxygen, which our bodies need to breathe, and they help us to digest the food we eat. Bacteria are also helpful because they are used in medicine to help us overcome disease. Bacteria are harmful because they can cause tooth decay and illnesses that can be either common or quite serious.
D the expansion of their territory
PHYSICAL DEVELOPMENT involve growth and changes in ......... Physical development in humans starts from infancy up to late adolescent. Features of physical development include: development of motor skills, puberty, development of muscle and physical coordination, etc.
