What are eukaryotic cells?
Animal, plant, fungi and protista cells are examples of eukaryotic cells. They are cells with membranes around organelles ( nucleus ). All the different organelles of a cell are called utrastructures and this includes: nucleus, golgi apparatus, ribosomes, mitochondria, ER, lysosomes, plasma membrane and cell wall.
Nucleus: It controls all cell activities and genetic information ( DNA ). The nucleus and the cytoplasm is called the protoplast.The nucleus is divided into 4 different parts which are the nuclear envelope, nuclear pores, nucleoles and heterochromatin.
Golgi apparatus: this is a series of membranes, bond sacs, which transport and store the proteins made in the ribosomes.
Ribosomes: Very small organelles made of equal amounts of protein and RNA. They are the sities of protein synthesis and they are mainly found in the ER ( endoplasmic reticulum ). Their size is of 80s in eukayotic cells.
Lysosomes: Spherical sacs ( suicide sacs ). Contain digestive enzymes, concerned with the breaking down of molecules. They contain digestive enzymes.
Mitochondria: this is where aerobic respiration takes place. It is a double membrane. Inside the mitochondria there is the matrix, DNA, phosphate granules and ribosomes.
ER: a system of flattened, membrane bounded sacs called cisternal, forming tubes and sheet. Sometimes it has ribosomes attached to it ( rough ER ) but if it doesn't it is called smoth ER.
Cell surface membrane: also called plasma membrane, it controls exchange between the cell and its enviroment. It is partially permeable.
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