Transcript Introduction to Animal Cells

Introduction to Animal Cells
Characteristics of Animal
Cells
• They are eukaryotic cells, that means they
contain a membrane bound nucleus
• They lack a cell wall that plant cells have
• Generally they are larger and more
complex than prokaryotic cells
• Contains membrane bound structures
called organelles
Plasma Membrane
• Not an organelle
• Selectively permeable
• Defines boundaries of cell and ensures contents
are retained
• Made of proteins and lipids
– Phospholipid bilayer
Nucleus
• Considered the “Control Center” of the cell
• Controls cell activity
• Contains nearly all of the cell’s DNA
Nucleolus
• Small, dense region within the nucleus
• The beginning site of protein assembly
Nuclear Envelope
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Double membrane that surrounds nucleus
Protects and isolates cell DNA
Selectively permeable
Contains thousands of nuclear pores that
allow material to move into and out of the cell
Centrioles
• Located near the nucleus
• Help to organize cell division in animal
cells
Ribosomes
• Most numerous and smallest organelle
• Composed of RNA and proteins
• Found throughout cytoplasm and attached to
Rough Endoplasmic Reticulum
• Site of protein synthesis
• Made of 2 subunits
Endoplasmic Reticulum (ER)
• Site where lipid components of cell
membrane and proteins are assembled
• Site of preparation of material to be
exported from the cell
• Two types
– Rough ER
– Smooth ER
Endoplasmic Reticulum
cont.
• Rough ER
• Smooth ER
– Has ribosomes
attached to surface
– Portion of ER
involved in protein
synthesis
– Lacks ribosomes
– Contains enzymes
that are specialized
detoxify drugs and
synthesize
membrane lipids
Golgi Apparatus
• Site of protein processing, sorting,
packing, and transport from ER to be
secreted from the cell
Mitochondria
• One of the largest organelles
• Breaks down sugar molecules stored in
food and converts them to chemical
energy for use by the cell (ATP)
• Contain their own DNA, RNA, and
ribosomes and are able to reproduce
themselves
Mitochondria
• The “powerhouse” of the cell
cont
Lysosomes & Peroxisomes
• Similar in both structure and function
• Lysosomes
– Filled with enzymes to breakdown and digest dead
organelles and proteins not being used
• Peroxisomes
– Detoxifies hydrogen peroxide and other harmful
compounds
– Plays a part in the oxidative breakdown of fatty
acids in animal cells
Vacuoles
• Saclike structure
• Storage area for the cell
• Stores materials like water, salt, proteins
and carbohydrates
Cytoskeleton
• Network of protein filaments that help cell
maintain its shape
• Involved in movement of cells