Answer:
Animal cells and plant cells
Answer:
e.) If exposure to cowpox gives immunity to smallpox in milkmaids, then milkmaids have a natural immunity and their blood should be used to develop a smallpox vaccine.
Explanation:
- Milkmaids who suffered from cowpox did not suffer from smallpox i.e. they were immune to the disease.
- If milkmaids did not suffer from smallpox then there must be some element of immunity that they received once they had recovered from cowpox, this would likely be found in their blood as antibodies.
Answer:
Oxygen or Minerals or Sugars (Oxygen is the most relevant one)
Explanation:
To survive, every cell must have a constant supply of vital substances such as sugar, minerals, and oxygen, and dispose of waste products, all carried back and forth by the blood cells. Without these substances, cells would die in a very short period of time.
Answer:
Figure 3
Explanation:
A mixture is a substance made up of two or more different kind of atoms arranged in such a way that they are not chemically linked or joined. This accounts for the reason a mixture can be separated easily. In the figures attached as an image in this question:
- Figure 1 represents an element because it is made up of only hydrogen atoms chemically bonded together to form a molecule.
- Figure 2 represents a compound because it contains hydrogen and carbon atoms chemically joined together.
- Figure 3 represents a MIXTURE because it contains the oxygen and carbon atoms, which are not chemically joined to one another. As seen in the image, the oxygen atoms are not joined to the carbon atoms.
- Figure 4 represents a compound because it contains oxygen and hydrogen atoms chemically bonded together.
The answer is D
One way to remember this is when you are building a bridge there is one piece right in the middle that keeps the whole thing from collapsing that is called the key-stone. If a keystone species goes extinct then the rest of the ecosystem will crumble around it.
