Answer:
I would have to say that A is the best choice
Explanation:
This is because all the other choices is not what the question is asking you for.
Answer: Cell
Explanation:
The cell is the structural and functional unit of life. It is the the most basic level. A life starts from a single cell.
When a male and female gamete(germ cell) fuse together they form zygote. Firstly it is a single cell surviving inside the mother's womb.
Then differentiation takes place and the cell keeps on dividing to form different tissue layers and then organs form which makes a complete baby. Hence, zygote and germ cell are cellular level of organization.
Answer:
They once thought that humans came from monkeys and apes but now they think they come from a ancient ancestor not from the monkey or ape family.
Explanation:
Answer:
A. Increasing surface area to improve nutrient absorption between the digestive and the circulatory systems.
Explanation:
Our intestines, on the inside, are lined with the intestinal mucosa. This mucosa is not straightened, as it might seem macroscopically; it rather has this wavy appearance forming folds. Also, epithelial cells in this mucosal layer have lots of small finger-like extensions called the villi.
Folds and villi increase the contact surface between the nutrients in the lumen and mucosa, thus increasing the rate of absorption of these nutrients between the intestines and the blood vessels below the epithelium.
In metaphase I of meiosis I, the pairs of homologous chromosomes, also known as bivalents or tetrads, line up in a random order along the metaphase plate. The random orientation is another way for cells to introduce genetic variation.
