Answer:Carbon has four valence electrons, so it can achieve a full outer energy level by forming four covalent bonds. When it bonds only with hydrogen, it forms compounds called hydrocarbons. Carbon can form single, double, or triple covalent bonds with other carbon atoms.
Explanation:
Answer:
Ecologist
Explanation:
"Ecologists study the interrelationships between organisms and their environments." (Environmentalscience.org)
You didnt exactly put in any answer options...
But here is my answer: Comparing a desert to Mars, i would say that
A desert has oxygen
And mars has carbon dioxide
A desert has sand
Mars has a rocky surface
Mars is a planet
A desert is not
The things i could think of that a desert and planet mars can relate to...I would say they both have heat and both sometimes have dust storms.
I think the statement “the human digestive system is very efficient at squeezing everything it can out of any food?" refers to the way the stomach is good at absorbing the wanted nutrients and keeping them in the body, while disposing of the unwanted waste and toxins. The biomolecules are broken down to preserve only certain nutrients within the molecules.
There's 39 chromosomes in the sperm cell. Why? Because sperm cells are gametes and therefore they are haploid cells meaning they have half the number of chromosomes of a regular cell or diploid cell.
78 / 2 = 39
