Cell Study Guide

Both animal and plant cells have some similar structural elements. First off they are both eukaryotic, which means they have a defined nucleus. The nucleus contains chromosomes. It is protected and surrounded by the cytoplasm, which is a watery or gel-like liquid. Further, animal and plant cells have a cell membrane that surrounds the cell. This allows for the cell to exert control, in most cases, over what can penetrate the cell, and what cannot.
One of the primary differences between animal and plant cells is that plant cells have a cell wall made up of cellulose. This helps the plant cells to allow high pressure to build inside of it, without bursting. A plant cell has to be able to accept large amounts of liquid through osmosis, without being destroyed. An animal cell does not have this cell wall. If you start to fill the animal cell with too much distilled water or other fluid, it will eventually pop.
Plant cells also are different from animal cells because they use photosynthesis to covert sunlight into needed food for the plant. Plant cells have chloroplasts, which has its own DNA, essentially directing the work of the chloroplasts.
Also plant cells, if one could view them under the microscope, appear extremely different than an animal cell because of the presence of a large vacuole, which exists in the cell’s cytoplasm. It usually takes up most of the room in the cell, and the membrane of the cell encircles it. It contains waste materials, water, and nutrients that can be used or secreted as necessary.
Animal cells have small vacuoles and may have numerous ones. They never have the large single vacuole that takes up most of the space in plant cells. As well, under the microscope plant cells often have a more regular shape. Animal cells tend to vary greatly in appearance.
Animals cells and plant cells have many similarites and many differences. In both plants and animals, cells form the building blocks for the parts of the organisms from lungs, heart, petals, stems and every other part. They all have a nucleus which dictates the role of the cell, its function and carries the genetic code. The function of each cell depends on which parts of the genetic code are ‘switched’ on in both plant and animals cells.

However, there are differences, the primary one being that plant cells have cell walls. In animal cells, the cells themselves play little part in prividing supportive structure for the organsims. This is carried out by structures like bones, exoskeletons and specific structural parts created by cells. In plants, however, the cells themselves are important in maintaining the structure.
Each plant cell is surrounded by a rigid cell wall. This is made from a material called cellulose which is starch based and forms a rigid structure. To use this rigidity, the plant cells have a liquid called sap inside their cellular space or vacuole. When this is full of as much water as it can absorb, it pushes outwards, placing pressure on the cell wall and keeping the cell in its turgid shape. This is called turgidity. In animal cells there is no need for a cell wall but animal cells and plant cells both have cell membranes.
In a plant, the cell membrane is used in a specific way. It is selective or semi-permeable. This simply means that, due to its chemistry, it allows some particles in (like water and dissolved glucose) while keeping others out (like certain toxins). This means that a plant cell can keep absorbing water until the concentration of water on both sides of the membrane is equal and sometimes beyond that, which results in them being able to obtain nutrients dissolved in the water because plants only take nutrients in in solution.
Plant cells also have organelles within them. These can be of different ypes and include chloroplasts – where pigments for photosynthesis are stored and mitochondria – which are the powerhouses of the cell and oxidise food substances to release energy. In the chloroplasts are the grana and stroma in which the different stages of photosynthesis occur (the dark and light phases), animal cells do not need these organelles because they take in nutrients directly from surrounding fluid – the animal takes them in orally.
So plant cells and animal cells have much in common but due to their different roles within the organisms they have definite differences too.