Transcript Cell Organelles

Cell Structure and Organelles
Unit 2 - Cells
Cellular Boundaries
PAGE 203-204
Cell Membrane
• Surrounds all cells in a double layer of lipids!
• Is selectively permeable
▫ Some things can get in/out, others cant
• MAIN FUNCTION
▫ Regulates what enters and leaves
▫ Protection
▫ Support
Cell Wall
• Found outside of the cell membrane
• Found in
▫ Plants
▫ Fungi
▫ Algae
▫ Prokaryotes
• MAIN FUNCTION:
▫ Provide support – helps plants stand vs. gravity
▫ shape
▫ Protection
Cell Organization on the Inside!
PAGE 196-197, 199
Nucleus
• All Eukaryotes including plants and animals have a
nucleus
• MAIN FUNCTION
▫ Contains DNA (in the form of chromatin)  coded
instructions for making proteins & other molecules
• Contains the following parts ▫ Nuclear Envelope
 membrane for protection and to allow RNA & proteins in
and out (through nuclear pores)
▫ Nucleolus
 Makes ribosomes!
Cytoskeleton (Cytoplasm)
• MAIN FUNCTION
▫ Made up of protein pieces that helps give the cell shape.
▫ Involved in many forms of cell movement
▫ Houses most of a cells organelles
Organelles That Store, Clean Up,
and Support
PAGES 198-199
Vacuoles
• MAIN FUNCTION – storage area for water, salts,
proteins, and carbohydrates
• A sac-like structure
• Many plant cells have a single, large vacuole filled with
liquid.
▫ Helps to support heavy structures such as stems and leaves
• Also found in single-celled organisms and animal cells.
Vacuole in a Plant Cell
Notice how much
room the vacuole
takes up in the
cell!!!
Vesicles
• Found in all EUKARYOTIC cells
• MAIN FUNCTION
▫ Store and move materials between organelles and
to the cell surface
Lysosomes
• Filled with enzymes
• MAIN FUNCTION
▫ Break down lipids, carbohydrates, and proteins from
food into particles that can be used by the cell
▫ Break down organelles that are no longer useful
Centrioles
• MAIN FUNCTION
▫ used in cell division to separate chromosomes during
mitosis
• Usually only found in animal cells in the cytoplasm
Organelles That Build Proteins
PAGE 200-201
Ribosomes
• One of the most important jobs in the cell is making proteins
▫ Free ribosomes work in the cytoplasm
▫ Bound ribosomes are stuck on the ER (they are what makes it a “rough”
ER!)
• MADE OF – small particles of RNA and proteins
• MADE IN – the nucleolus
• MAIN FUNCTION – make proteins
▫ They do this by following coded instructions that come from DNA in the
nucleus
Free and Bound Ribosomes
Endoplasmic Reticulum
• Rough Endoplasmic Reticulum
▫ Involved in making protein
▫ Has ribosomes on the surface (how it gets its name)
▫ MAIN FUNCTION: Modifies proteins
• Smooth Endoplasmic Reticulum
▫ No ribosomes on surface
▫ MAIN FUNCTION: Make lipids
Interesting ER Facts
• ((You should write these down!!)
• Cells that produce hormones have many
Smoother ER’s
▫ Example: testes and ovaries have LOTS of smooth
ER
• The liver is the main organ in your body for drug
and alcohol detoxification – therefore, the cells
of the liver have many smoother ER too!!
The Endoplasmic Reticulum
Rough ER
Smooth ER
Golgi Apparatus (Golgi Body)
• After proteins are made by the RER, they move to the
Golgi
• MAIN FUNCTION
▫ packages, sorts, stores proteins and other materials from
the ER.
Organelles That Capture and
Release Energy
Page 202
Chloroplasts
• Found in plants and SOME other organisms (bacteria and algae!!!)
• Animals and fungi do NOT contain chloroplasts
• Chloroplasts contain chlorophyll which makes a plant look green!
• MAIN FUNCTION
▫ use energy from the sun to make food through photosynthesis
Mitochondria
• MAIN FUNCTION – release energy from stored food molecules to
be used to power growth, development, and movement.
• Nearly all eukaryotes have mitochondria
• Important, cells that need more energy have more mitochondria.
▫ Muscles
▫ Heart