Animal cells have many organelles such as nucleus, endoplasmic reticulum, Golgi body, vesicles and mitochondria. Animal cells have non-membranous structure such as ribosomes and cytoskeleton. Some animal cells have flagella and cillia.
Internal structures and functions
- Consists of nuclear envelope, nucleolus and chromosome.
- Two layers of membranes, outer and inner membranes. Nuclear envelope surrounds the fluid portion, called nucleoplasm. It controls the movement of substance in and out from the nucleus.
- Nucleolus is the dark dense mass material in nucleus. It may be one or more nucleolus in a nucleus and has cluster of DNA and proteins.
- Chromosomes are threadlike structures that contain genetic information that is passed on from one generation to the next generation.
Endoplasmic reticulum continuous with nuclear envelope and extends to cytoplasm.
- Two types of endoplasmic reticulum: rough endoplasmic reticulum and smooth endoplasmic reticulum.
- Many ribosomes attach to the surface of rough endoplasmic reticulum. Ribosomes synthesize proteins.
- Smooth endoplasmic reticulum does not have ribosomes. It synthesizes lipids.
Golgi body composes of a series of flattened membrane-bound sacs.
- It contains enzyme which finishing protein and lipid, sort them out and package them inside vesicles for shipment to specific location.
- Vesicles (read more) are tiny, membranous sacs to transport or store variety of substances, digesting substances and structure in the cell.
- Mitochondria has double membrane system which has outermost membrane and inner membrane.
- Inner membrane fold inward to form cristae.
- Mitochondria functions as energy generating.
- An interconnected system of fibres, threads and lattices. It extends between the nucleus and plasma membrane.
- It provides the internal organization, shape and capacity of cell to move.
- Most of the cytoskeleton elements are permanent except some are appear only in certain period, example, spindles are formed before cell division and disappeared after division.
Flagella and cilia
- Flagellum (plural, flagella) and cilium (plural, cilia) are the examples structures of cell movement or motility.