Cells- biology

• All living things are made of cells. Cells can be either prokaryotic or eukaryotic. Eukaryotic cells are complex, they include all animal and plant cells. Prokaryotic cells are smaller and simpler, they can be bacteria cells.
• The different parts of a cell are called subcellular structures. A nucleus contains genetic material- it controls the activities of the cell. Cytoplasm is a gel- like substance, this is where most of the chemical reactions take place. Enzymes control these chemical reations. A cell membrane holds the cell together, it controls what comes in and goes out of the cell. Mitochondria is where most of the reactions for aerobic respiration take place. Respiration transfers energy that the cell needs to work.
• Plant cells have more sub-cellular structures than animal cells do. A cell wall is made of cellulose. It supports the cell and strengthens it. A permanent vacuole contains cell sap, a weak solution of sugar and salts. Chloroplasts are where photosynthesis happens, this makes food for the plant. They contain a green substance called chlorophyll, this absorbs the light needed for photosynthesis.
• Bacterial cells are much smaller. Bacterial cells are prokaryotic cells. They contain a cell membrane, cell wall, a single circular strand of DNA, plasmids, and cytoplasm. They don’t have a nucleus, chloroplasts or mitochondria.