Bell Work
• Where does cellular respiration take place in the cell?
• Where does photosynthesis take place in the cell?
Intro to Biology – Lecture 43
Cell Storage Facilities
Vacuoles
• Storage Bins (bubbles) in the Cells• Large in plant cells, small in animal cells• Plant cell volume depends on the size of the
vacuole.
Vacuoles
• In a factory, vacuoles would be storage facilities
• store food nutrients or water a cell might need to survive
• store waste products so the rest of the cell is protected from contamination
Vacuole Structure
• membrane that surrounds a mass of fluid
In Plants
• When water is scarce, vacuoles are empty and plants droop.
• When water is plentiful, plants stand tall because of the full vacuole.
• They still look like plants because the cell wall hold them up even with empty vacuoles.
Ribosomes
• Make Proteins (enzymes/support for other cell functions)
• Connect one amino acid at a time and build long chains to make proteins
• In a factory, ribosomes are the construction workers.
Where are Ribosomes
• In the cytoplasm (proteins used in the cell)• In the endoplasmic reticulum (proteins used in
the cell and transported outside the cell)
Ribosome Structure
• Eukaryotic Cells• Two subunits - 60-S (large) and 40-S (small)
• Prokaryotic Cells• Two subunits - 50-S and 30-S
Making Proteins
• mRNA made in the nucleus is sent to the ribsomes
• two subunits come together and lock onto the mRNA to start making the protein by pulling amino acids off of tRNA floating in the cell.
Endoplasmic Reticulum
• The packaging system of the cell• In a factory, it would be the packing center
The Endoplasmic Reticulum
• Works with the Golgi apparatus, ribososmes, RNA, mRNA, and tRNA.
The Endoplasmic Structure
• Rough ER• Has ribosomes attached to it• Looks bumpy
• Smooth ER• No ribosomes• Looks like tubes
Endoplasmic Reticulum
The Purpose of the ER
• Smooth ER - storage organelle• Stores steroids and ions
The Purpose of the ER
• Rough ER - When protein synthesis is completed by ribosomes they are sent to the Rough ER.
• It pinches off a vesicle. • That vesicle (bubble) can move to the cell
membrane or the Golgi apparatus.
The Process
Golgi Apparatus
• (Gogli complex, Gogle Body)• packaging organelle like the endoplasmic
reticulum (ER)
The Gogli’s Job
• Gathers simple molecules and combines them to make molecules that are more complex
• Big molecules are made into vesicles• builds lysosomes (cell digestion machines)• In plants, create complex sugars and send
them off in secretory vesicles.
How are Vesicles Created?
• In the same way the ER does it. • The vesicles are pinched off the membranes
and float through the cell.
Working with the ER
• When a protein is made in the ER, so is a transition vesicle. is made.
• Vesicles floats to the Gogli.• The Gogli uses what it wants, then releases it
with a secretory vesicle back to the cytoplasm.• The vesicle moves to the cell membrane and
the molecules are released out of the cell.
Gogli Apparatus
Gogli Structure
• A series of membranes shaped like pancakes. • The membrane surrounds an area of fluid
where the complex molecules (proteins, sugars, enzymes) are stored and changed.
• Because the Golgi complex absorbs vesicles from the rough ER, you will also find ribosomes inside.