Answer:
d. The dermis is usually thicker than the epidermis
It becomes positive because ATP synthase allows H+ ions to pass through the membrane .
Explanation:
The chest (thoracic or pleural) cavity is a space that is enclosed by the spine, ribs, and sternum (breast bone) and is separated from the abdomen by the diaphragm. The chest cavity contains the heart, the thoracic aorta, lungs and esophagus (swallowing passage) among other important organs.
Human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion. Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body. The process of digestion has many stages.
Answer:
Explanation:
An element only has <u>one</u> type of atom and cannot be broken down by chemical means.
Let's analyze the answer choices.
1. This has two types of atoms, so it cannot be an element. It has more than one type of atom.
2. This has two types of atoms that are bonded together. It cannot be an element because there is more than one type of atom and the bonds can be broken.
3. This has one type of atoms, so it is an element.
Therefore the best answer choice is 3.