why all life on the earth is ultimately depent on a continued supply of sunlight
Because Sunlight is our source of energy, or food.
Plants, the producers have chloroplasts on their cells that ours cells do not have. These chloroplasts absorbs sunlight’s energy to produce glucose using its chlorophyll, on which where the first order consumers eat the producer or the plant, the energy or food produced will be passed to the consumer, to the other, and to the other.
because sunlight is the number source of energy on earth. life starts due to sun. plants produce food by using sunlight in photosynthesis, the animals or herbivores eat plants that provide them energy, then they will be eaten by carnivores and use the energy that herbivore get from plants. sun also gives heat to us, without sun earth would probbably so cold that life cant exist.