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:
The blood brain barrier blocks chemicals from entering brain tissue.
Explanation:
A: Scientific knowledge can be revised with time.
The answer is logistic growth.
It is modeled by an S-shaped curve. Carrying capacity (K) is the maximum individuals of a population that a habitat can sustain indefinitely
given the limited resources in the environment. Before this number
is achieved, the population grows exponentially and slows as it gets close. When
the K number is reached, the stationary phase enters.