Wolves are predators, of deer, and without wolves, more deer survived and ate more forest plants.
Answer:
Sunspot: Appears in groups, and is a dark area on the sun
Solar flare: Occurs near sunspots, and Extends into corona
Prominence: Appears as a loop, and is made of cool dense gas
Explanation:
I took the quiz
Answer:
Plants can't use N2 as is so the first option is wrong. They do have relationships with bacteria that live in nodules of the root and convert the nitrogen into ammonia, a usable form for the plants. So the second option is correct. There are bacteria living in the soil as well that convert nitrogen to ammonia so technically option 3 is also correct. Again, nitrogen if present in water would be in the form N2 which is not usable by plants so 4 is wrong.
These are correct:
use bacteria to convert nitrogen to usable form
In obtain usable nitrogen compounds from the soil
Constructive forces build mountains and hills, and are caused by convergent plate boundaries
The body's first line of defense is actually the non-specific immune system which is also called innate immunity.
Innate immunity employs both physical and chemical barriers that form the first line of defense. These include:
1. The intact skin. The skin is made up of keratin in its outermost layer. Keratin makes skin tough and resistant and pathogens usually cannot penetrate unless the skin is broken.
2. The mucus membrane. This is a thin membrane that forms a protective lining inside many organs and other parts of the body such as the trachea. Mucus produced by the membrane traps bacteria and other harmful particle which are then expelled from the body.
3. Tears. Tears from our eyes contain lysozyme, a chemical that kills bacteria.
If the pathogen gets through or evades these types of defenses, then it is dealt with by the second line of defense which is called specific immunity or acquired immunity. It is here that white blood cells namely the B lymphocytes and T lymphocytes attack, kill or neutralize pathogens.
