Matter and energy always flow from the in ecosystems.
A. consumers to the producers
B. heterotrophs to the autotrophs
C. autotrophs to the consumers

When organisms use organic matter for cellular respiration, ALL the goes back into carbon dioxide, water, and minerals, while ALL the energy leaves the ecosystem as heat. So matter cycles, energy flows through ecosystems. So It is C

Explanation: A. The producers generate food for themselves and others; consumers do not produce anything, instead eating producers, other consumers or both.

B. Autotrophs make food for their own use, but they make enough to support other life as well.Heterotrophs cannot make their own food, so they must eat or absorb it.

So C is correct

fertilization, pictured in figure 24.23a is the process in which gametes (an egg and sperm) fuse to form a zygote. the egg and sperm each contain one set of chromosomes. to ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. in mammals, the egg is protected by a layer of extracellular matrix consisting mainly of glycoproteins called the zona pellucida. when a sperm binds to the zona pellucida, a series of biochemical events, called the acrosomal reactions, take place. in placental mammals, the acrosome contains digestive enzymes that initiate the degradation of the glycoprotein matrix protecting the egg and allowing the sperm plasma membrane to fuse with the egg plasma membrane, as illustrated in figure 24.23b. the fusion of these two membranes creates an opening through which the sperm nucleus is transferred into the ovum. the nuclear membranes of the egg and sperm break down and the two haploid genomes condense to form a diploid genome.

explanation:

label a cell membrane

label b cytoplasm

label c ribosomes

label d dna

the membrane forms the outside of the cell

cytoplasm is the liquid within

ribosomes are the components within that distribute rna

the dna is the genetic make-up