Cells

By: Arsalan Syed

What are Cells?

Cells are considered the basic units of life, this is what helps something live and die. Cells are important because one of the main things cells do to help us live is that it carries oxygen throughout our body. That's because all cells are surrounded by a structure called the cell membrane. Much like the walls of a house, the wall creates a boundary between the cell's internal and external environments. The cell membrane is sometimes also referred to as the plasma membrane.

Where do we find Cells?

Cells are found in any living object, person or a thing.Living cells are found everywhere on this planet unless the area is sterile. Run your fingers along a smooth wooden fence (even wood is composed of dead plant cells) and you will pick up cells of pollen, fungal spores, bacteria and probably green algae. Most of the cells will be too small to see without a microscope but you will probably have hundreds of cells on your fingers.

3 main parts of a cell

Are all cells the same?

Although all cells have some simular organelles and functions, they are not very alike at all. For instants cells have different jobs to do within the body, a cell can be a heart cell and another can be a liver cell. Another example is animal and plant cells are different, plant cells have no lysosomes and have a cell wall instead of a membrane. Plant cells also have chloroplasts which make the green color of the plant.

If cells makes up is what makes up a cell?

Cells are made of organic molecules, such as lipids, carbohydrates, nucleotides and amino acids. The cell uses chemical energy to make polymers of these molecules, for example to make DNA and RNA strands from nucleotides and proteins from amino acids. Cells also contain inorganic molecules, such as salt and metals in small amounts, and lots of water, too.

What is osmosis and diffusion?

Osmosis is the result of diffusion across a semipermeable membrane. If two solutions of different concentration are separated by a semipermeable membrane, then the solvent will tend to diffuse across the membrane from the less concentrated to the more concentrated solution. This process is called osmosis. At the cellular level, both processes are types of passive transport.

How long do cells live?

It depends. The cells that line your digestive system turn over very rapidly. Brain cells last a very long time. In fact, scientists thought that once our brain finished growing, the cells we start with are the only ones we'll ever have. Over the past few years, scientists have figured out that brain cells do get replaced. This has changed the way we think about the potential of the brain to recover from some kinds of injuries or illnesses.