1) B
(I'm not so sure of this one) All of the other options have a steady impact on population regardless of the density of organisms except competition
2) D
Increased carbon dioxide levels would not hinder plant growth, and tsunamis aren't really linked to carbon dioxide levels. Increased carbon dioxide is unlikely to lower the air temperature so only D is left.
3) A
4) Three properties of water that allow it to sustain life are that it is adhesive, it is a good solvent, and cohesion. Adhesion is important in situations such as water travelling up xylem tubes in plants so that the water is not pulled down by gravity and can reach parts of the plant that need water. Cohesion allows the water being pulled up the xylem to stay together and for water molecules to be pulled when a neighbouring one is moved. Water being a good solvent allows inorganic minerals to be taken with water through vascular tissue, such as in the previous example.
The summer solstice is the first day of summer. This day, June 21, is the longest day of the year.
<span> In </span>animal cells centrioles<span> organise the pericentriolar material to produce microtubules including mitotic spindle fibres.</span><span />
Answer:
A) They form chemical bonds with other atoms
Explanation:
In chemistry, a valence electron is an outer shell electron that is associated with an atom, and that can participate in the formation of a chemical bond if the outer shell is not closed; in a single covalent bond, both atoms in the bond contribute one valence electron in order to form a shared pair.
That is what we call the muscular system. This system allows us to move, circulates blood through the body and their is 3 types of muscle. Skeletal muscle is voluntary and are mostly attached to two bones. Smooth muscle is found inside organs such as stomach and blood vessels. And Cardiac muscle is ONLY found in the heart .