A species is a group in which all member have common characteristics and can produce fertile offspring.
2. The populations of predators are dependent on the populations of their prey.
The correct option is B.
The blood brain barrier is designed to prevent the passage of some substances such as drugs from the blood stream into the brain. The blood brain barrier is made up of high density cell barriers which restrict passage of substances into the brain area.
In photosynthesis, the light-dependent reaction takes place on the thylakoid membranes. The inside of the thylakoid membrane is called the lumen, and outside the thylakoid membrane is the stroma, where the light-independent reactions take place.
The "light-independent" or dark reactions happen in the stroma of the chloroplasts. This is also known as the Calvin Cycle.