Cell Components
Cytoplasm is made of a clear fluid (cytosol) inside the cell. Organelles float throughout the cytosol.
Cytoskeleton – a supportive and structural network inside the cell. Think of 2x4s inside the cell; structural support and anchor for organelles. It also allows for transport along the cytoskeleton.
Ribosomes are involved in protein synthesis and composed of protein and RNA. They can be free floating in the cytoplasm and make proteins for cytoplasm. Ribosomes can be attached to the Endoplasmic reticulum, and make proteins that travel through Endoplasmic reticulum.
Endoplasmic Reticulum – a network of membranes, flattened sacs, and vesicles. It provides a tubular transport system inside the cell for synthesis reaction. Rough endoplasmic reticulum – rough ER has ribosomes attached and functions in protein synthesis (named because it looks rough under a microscope because of the attached ribosomes). Smooth endoplasmic reticulum – smooth ER – does not have ribosomes and is involved in lipid synthesis.
Vesicles – membrane bound sac for transport through the cell. The vesicle membrane is made of phospholipids (like the cell membrane). They are the UPS delivery service of the cell, transporting packages throughout the cell. They can transport from organelle to organelle, such as ER to Golgi apparatus. Vesicles can also bind with the cell membrane and release products outside cell.
Golgi apparatus – flattened sac that refines, packages, and modifies products. The final packaging and modification. Products can be released in vesicles that are used in the cell or transported out of cell. Vesicles combine with cell membrane to secrete its contents out of the cell.
Mitochondria produce energy for the cell; this is where ATP is produced with aerobic respiration. Often called the powerhouse of the cell, two membranes are characteristics of mitochondria. The inner membrane is folded into cristae, which are where enzymes for ATP production are located. Cells that require more energy have more mitochondria. For example, active muscle and tissue with high metabolic demand have more mitochondria than adipose cells (fat).
Lysosomes contain digestive enzymes for breaking down bacteria and old cellular components. Often called the garbage disposals of cells.
Peroxisomes break down lipids, alcohol, and rare biochemicals with catalase and oxidase enzymes. Involved with destruction of bile acids. Abundant in liver and kidney cells.
Microtubules and microfilaments – structural components of cells. Think of 2x4s for frame work of house. Major component of the cytoskeleton.
Cilia – tubular extensions of the cell used for motility. In the respiratory system, multiple cilia beat to move mucous past the cell. Many cilia are often on the outside of a cell.
Flagella – long, tubular extension provides motility for sperm in reproduction. One flagella per cell.
Centrosomes – two hollow cylinders involved in chromosome separation during cell division. Spindle fibers attach to centrosomes to pull cell components.
Cell Nucleus – where the DNA is kept. Double layered membrane protects DNA. There are nuclear pores that allow the passage of allowed substances.
Nucleolus – composed of RNA and protein, site of ribosome production.
Chromatin – loosely coiled DNA.