<span>Certainly. Every organism has a variety of different characteristics. One person writing a key might choose to use different characteristics than another person would use.
For example: Here's a key for separating fish, snake, frog and mouse
1.
A. Has scales on its skin ... 2
B. Has no scales on its skin ... 3
2.
A. Breathes with gills - fish
B. Breathes with lungs - snake
3.
A. Has hair or fur - mouse
B. Has no hair or fur - frog
Here's a different key for the same four animals:
1.
A. Has four legs ... 2
B. Does not have 4 legs ... 3
2.
A. is warm-blooded - mouse
B. is cold-blooded - frog
3.
A. has fins - fish
B. has no fins - snake</span>
66% of new HIV infections occur in sub-saharan Africa.
The answer to the question above is letter D. <span>Chromosomes found in the cell nucleus.</span>
In the cell nucleus, DNA is tightly packed into the
thread-like structure known as chromosomes. Every chromosome is made up of
tightly coiled DNA around proteins (histones) that support its structure.
Chromosomes are not visible when there is no cell division. It cannot be seen
in the cell’s nucleus nor under the finest microscope. They are only visible
when the cell is dividing and is apparently visible under a microscope.
The answer is "<span>B: all the gray squirrels that live in a forest" </span>
In animals, the circulatory system performs a similar function because it transports vital nutrients around the body of the animal, just like how xylem and phloem transport water, minerals, and sugar to different parts of the plant.