Activation energy is the amount of energy required to begin a chemical reaction.
<h2>When too walk your dog you are using energy from the sunlight to power this activity</h2>
Explanation:
The ultimate source of energy in the ecosystem is the sun. When we take our dog for a walk, we are utilizing energy stored in our body that we obtained food. We must have obtained that from either plants or animals. The animal in turn must have obtained its food from plant. Plants are the organisms in the food chain who can convert the energy from the sun into the chemical energy. So, we can say that when we walk our dog we use energy from the sunlight to power this activity.
Breathing is the exchange of gases between animals & the environment.
Answer:
C.
Explanation:
Human reproduction is any form of sexual reproduction that results in fertilisation by humans. It normally includes a man and a woman having sexual intercourse. During sexual intercourse, the contact between male and female reproductive systems leads to the woman's ovum being fertilised by the man's sperm.
In human fertilization, a hapoloid ovum is released that fuses with a haploid sperm and produces a single 2n diploid cell called the zygote.
Hence, the correct option is C.
