Sunlight is required for all cellular organisms on earth, because all organisms are either photosynthetic or dependent on a photosynthetic organism.
a. true
b. false

True

Explanation:

The sunlight is required for the living organism because all the living organism on the earth are either autotrophs or depends on the autotropic organism for their survival.

The green plants perform the process of photosynthesis by trapping sunlight. The other organism depends on the plants for their survival.

Hence, the given statement is true that all the living organism depends directly or indirectly on the sunlight.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.