Answer:
3. the absence of a cell wall in human cells
Explanation:
Animal cells do not have cell walls. Cell membranes separate the cytoplasm of the animal cells from the surroundings and maintain their interior. Plant cells have cellulosic cell walls. A cell wall surrounds the cell membrane of a plant cell. Cell walls serve to provide structural support and protect plant cells from pathogens. Cell walls also help keep excess water out of cells so they do not burst. Therefore, human cheek cells would not have cell walls while the onion cells would have cell walls made up of cellulose.
Answer:
Each ion or charged molecule in a fluid contributes to the fluid's overall electric charge. A difference in charge between two regions of fluid can affect the rate and direction of diffusion between them. For example, positively charged substances will tend to diffuse toward a region with an overall negative charge.
Explanation:
Answer:
Cells and atoms both work together to be a physical shape
Explanation:
You are made up of cells much as say a fridge is made up of atoms. The cell is also broken down into several parts such as the mitochondria, vascoles, and the smooth endoplasmic reticulum.
Adenine, thymine, cytosine and guanine are the four nucleotides found in DNA.