Hope this helps !! :) good luck
Answer:
The correct answer would be zygote...blastocyst...embryo...fetus.
The fertilization of sperm and egg results in the formation of zygote. It receives genetic material from a male as well as a female parent.
It divides with the help of mitotic divisions and results in the formation of 2, 4, 8, and 16 celled stages.
It results in the formation of the hollow spherical ball of cells termed as a blastocyst. The cells are distributed to form the outer layer termed trophoblast and inner cell mass which gives rise to the embryo.
Trophoblast help in the implantation of the blastocyst into the uterine wall.
The cells of the embryo undergo organogenesis during different organs such as heart, brain, lungs et cetera are formed.
In humans, almost 9 weeks after the fertilization the developing embryo is considered a fetus.
The fetus development continues until birth.
DNA replication only happens during meiosis because the chromosome number of the species remains the same from one generation to the next, the chromosome number of germ cells must be reduced by half during meiosis. To achieve this feat, meiosis, unlike mitosis involves a single round of DNA replication followed by two rounds of cell division.
Answer:
on channel-linked receptors, G-protein-linked receptors, and enzyme-linked receptors.
The ability of cells to communicate through chemical signals originated in single cells and was essential for the evolution of multicellular organisms. In multicellular organisms, cells send and receive chemical messages constantly to coordinate the actions of distant organs, tissues, and cells. Cells can receive a message, transfer the information across the plasma membrane, and then produce changes within the cell in response to the message. Single-celled organisms, like yeast and bacteria, communicate with each other to aid in mating and coordination. Cellular communication has developed as a means to communicate with the environment, produce biological changes, and, if necessary, ensure survival.
If we didn't have sun's energy there wouldn't be life on earth.Sunlight is what plants eat. Animals and bugs eat the plants that have sunlight in them. Humans and other animals then eat the bugs and the animals that ate the plants. Indirectly every living thing has sunlight feeding it.
Hope this helps!
