Cell Structure Flashcards
Describe a lysosome
Round organelle surrounded by a membrane
Contains digestive enzymes
Describe a ribosome
Small orgamelle that floats freely or is attached to rough ER
Made up of proteins, not surrounded by a membrane
Site of protein synthesis
Describe rough ER
Membranes encolsing fluid-filled spaces that is covered in ribosomes
Folds and processes proteins made at ribosomes
Describe smooth ER
No ribosomes
Synthesises and processes lipids
Describe golgi apparatus
A group of fluid-filled, membrane bound, flattened sacs (vesicles often seen)
Processes and packages new lipids and proteins + makes lysosomes
Describe mitochondrion
Double-membrane bound organelle containing cristae (inner fold) and matrix (contains enzymes for respiration)
Site of aerobic respiration
Describe a centriole
Small, hollow cyliners made of microtubules (tiny protein cylinders)
Found in animal cells and SOME plant cells
Involved in separation of chromosomes during cell division
Describe nucleus
Large organelle surrounded by a nuclear envelope containing pores
Nucleus contains chromatin and the nucleolus
Controls the cells activities: DNA contains instructions to make proteins, pores allow subtsances to move in and out and nucleolus makes ribosomes
Where are proteins made?
Ribosomes
Where do ribosomes on the rough ER go after?
Make proteins that are excreted or attached to cell membrane
Where do free fooating ribosomes go?
They make proteins that stay in the cytoplasm
Describe protein production and transportation
- New proteins made on the rough ER are folded and processes eg. Sugar chains added
- Trasnported from the ER to golgi apparatus in vesicles
- Proteins undergo further processing eg. Sugar chains trimmed
- Proteins enter more vesicles to be transported around cell
For cell/tissue/organisation - see Biology January Mock ‘control of gene expression’
:)
What do prokaryotes not contain that eukaryotes do?
Prokaryotes do not contain any membrane-bound organelles
