Cell Organelles Edwin P. Davis, M.Ed.

Animal Cell Nucleus 2 Cell Types No nucleus Nucleus Cell Organelles  organs in a cell Most important = nucleus (controls all cell functions) Nucleus:Cell :: brain:body 2 Cell Types Prokaryote Eukaryote No nucleus Nucleus No membrane bound organelles Membrane bound organelles Simple Complex Contains: cell wall, cell membrane, and ribosomes Contains: nucleus and organelles Bacteria only Plants/animals/fungus

Types of Cells

Types of Cells

Organelles are small, specialized structures in cells which operate like organs by carrying out specific tasks.

Eukaryotic Nucleus The nucleus stores chromatin (DNA plus proteins) in a gel-like substance called the nucleoplasm. The nucleolus is a condensed region of chromatin where ribosome synthesis occurs. The boundary of the nucleus is called the nuclear envelope. It consists of two phospholipid bilayers: an outer membrane and an inner membrane. The nuclear membrane is continuous with the endoplasmic reticulum. Nuclear pores allow substances to enter and exit the nucleus.

Nucleus Nucleus – control center (contains chromatin) Nuclear membrane Nucleolus Chromatin Nucleus – control center (contains chromatin) Chromatin – Tangles of DNA Nucleolus – A small, dense region in the nucleus where the assembly of proteins begins

Ribosomes Cytoplasm Found on the endoplasmic reticulum or cytoplasm Site of protein synthesis Makes proteins using coded instructions from the nucleus Ribosomes Cytoplasm Liquid between the nucleus and cell membrane Suspends organelles A place for chemical reactions and transport

Endoplasmic Reticulum Folded membrane (increased surface area) Assembly and transport of proteins and lipids Rough ER has attached ribosomes

Golgi Apparatus (body) Packaging and shipping of proteins and lipids Packaged into vesicles Vacuole Storage of food, water, and waste Larger in plant cells – usually contains water

Mitochondrion Produces Energy (ATP) for the cell Inner folded membrane increases surface area

Cilia Short hair-like projections from the membrane Cell movement Flagella Long whip-like structure that extend from the cell membrane Usually 1 or 2 on a cell

Cytoskeleton Cell Membrane Helps a cell keep its shape Serves as the cell's boundary from its environment and regulates which materials enter and leave the cell

Centrioles - Found in animal cells Centrioles - Found in animal cells. Organizes the chromosomes during cell division. Chromatin - A granular material made up of DNA bound to protein Chromosome - Threadlike structure that contains genetic information. Nuclear Envelope - A double membrane that surrounds the nucleus.

Lysosomes - Contains enzymes that break down lipids, carbohydrates, and proteins

Lysosomes Enzymes within the lysosomes aid the breakdown of proteins, polysaccharides, lipids, nucleic acids, and even worn-out organelles. These enzymes are active at a much lower pH than that of the cytoplasm. Therefore, the pH within lysosomes is more acidic than the pH of the cytoplasm.

Plastids are double membrane bound organelles found inside plants and some algae, which are primarily responsible for activities related to making and storing food. Many plastids are photosynthetic but some are not.