Answer: A. Chemical signal
Explanation:
Chemical signal is the type of communication which coordinates actions between neighboring cells
.
This ability originated in single cells organisms and was essential for the evolution of multicellular organisms because after a cell receives a message, it is transferred across the plasma membrane and changes are brought about within the cell in response to this message.
Eutrophication results in the death of trout and other fish as a result of asphyxiation from the lack of oxygen. Eutrophication involves the enrichment of water by nutrients salts such as phosphates, nitrates among others, that causes structural changes of the aquatic ecosystem such as; increased production of algae and aquatic plants, depletion of fish species, deterioration of water quality and other effects that impact negatively the aquatic ecosystem.
Answer:
B
Explanation:
in photosynthesis CO2 is used to produce glucose NOT energy.
in cellular respiration O2 is used to produce energy NOT CO2.
in cellular respiration oxygen is used to produce energy and CO2.
Answer:
The correct answer is D. zygote and finally develops into a fetus
Explanation:
Zygote is formed by the fusion of male gametes and female gametes. It is considered as the first stage of development of a baby. Zygote is a unicellular structure which develops into an embryo which is a multicellular structure.
Then this embryo develops and is called a fetus at the starting of the 11th week of pregnancy. A developed fetus is the final stage of prenatal development.
Therefore during successful prenatal development, a human baby begins as a zygote and finally develops into a fetus. So the correct answer is D.
Carbon dioxide and photosynthesis
