Answer:
the answer is all of the above
<span>Crossover is the first way that genes are shuffled to give rise to genetic diversity. Crossover takes place in sexual reproduction. Chromosomes line up side by side and break off pieces of themselves, then trade those pieces with each other. When they break at the same place (locus) in the sequence of base pairs, the result is an exchange of genes called genetic recombination. That is the normal way for crossover to occur. Genetic recombination ensures that the daughter cells produced have a different genetic makeup from the parent cell and thus diversity is created.</span>
Claim: No tools to discover the impending Cell Theory.
Reasoning:
Schleiden and Schwann, as well as Virchow, are generally seen as the founders of the cell theory, due to their pioneering scientific work in the 1800s. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.
Evidence: The cell theory has many complexities and is of importance due to its affect to nearly every aspect of biology, from our comprehension of life & death, managing diseases, cycles and etc. But early scientists had no tools to study cells. They didn't even know about them. It took the invention of the microscope to view them and to begin an understanding of cells.
(Two Dutch spectacle-makers and father-and-son team, Hans and Zacharias Janssen, create the first microscope.) Matthias Schleiden observed that all plants were made of cells from the microscope and Theodor Schwann observed that all animals were also made of cells. Rudolf Virchow observed that cells only come from other cells Virchow saw cells dividing and added that living cells arise only from other living cells. These ideas led to cell theory, which states that all organisms are made of cells, all life functions occur in cells, and all cells come from other cells.
Answer:
B. A sperm cell
Explanation:
Meiosis creates gametes/sex cells, such as the sperm and egg.
So, sperm cells are formed by meiosis.
Meiosis doesn't create fertilized eggs, it instead creates normal egg cells.
Meiosis also doesn't create heart and bacterial cells because those are made in mitosis.
So, B is the correct answer.
