Eukaryotic Organelles and Functions ✅ Flashcards
Draw and label a eukaryotic cell.
.
What are two types of organelles are there in eukaryotic cells?
non-membranous and membranous
What are the non-membranous cell organelles in the eukaryotic cell?
- Ribosomes
- Microtubules
- Microfilaments
- Chromosomes
What are the membranous cell organelles in the eukaryotic cell (one membrane)?
- Plasmolema
- Endoplasmic reticulum
- Golgi apparatus
- Lysosomes
- Vacoules
What are the membranous cell organelles in the eukaryotic cell (two membrane)?
- Mitochondria
- Plastids
- Nucleus
- Chloroplasts
What does the endomembrane system include?
- Nuclear envelope
- Endoplasmic Reticulum
- Golgi Apparatus
- Lysosomes
- Vesicles
- Plasma membrane
What does the ER enclose?
A series of intercommunicating channels called “CISTERNAE”.
What does ER stand for?
Endoplasmic Reticulum
What is the function of the ER?
ER is a major site for vital cellular activities:
- biosynthesis of proteins
- biosynthesis of lipids.
What are the two types of endoplasmic reticulums?
- rough ER
- smooth ER
What is the function of the rough ER?
The rough ER is the site for the synthesis of most membrane-bound proteins.
(production of membrane-associated proteins, proteins of many membranous organelles, and proteins to be secreted by exocytosis.)
What is the function of the smoth ER?
1) lipid biosynthesis,
2) detoxification of potentially harmful compounds,
3) sequestration (storing) and controlled release of Ca2+ ions.
How does the rough ER look like?
- saclike and parallel stacks of flattened cisternae,
- cisternae are limited by membranes that are continuous with the outer membrane of the nuclear envelope
What is a ribosome?
A ribosome is a complex structure, containing many different proteins and at least three ribosomal RNAs.
What is the function of ribosomes?
Ribosomes are a site of protein synthesis.
What do free ribosomes synthesize?
Free ribosomes synthesize PROTEINS for USE in the CYTOPLASM.
What do ribosomes bound to the ER synthesize?
Ribosomes bound to the endoplasmic reticulum membrane synthesize PROTEINS that are EXPORTED from the cell or INCORPORATED into the membrane.
What is the sedimentation coefficient?
The sedimentation coefficient (s) of a particle characterises its sedimentation during centrifugation.
What is “protein trafficing”?
The movement of newly synthesized proteins in a cell.
What is protein traffic characterised by?
Protein traffic is characterised by common principles that make up protein targetting molecular mechanism.
What is the role of the endomembrane system?
Modify, package, and transport lipids and proteins.
What is the effect of protein trafficing?
- Protein activity and stability are changing.
- Proteins are targeted to specific sites in the cell or secretion to the outside of the cell.
Why does the RER have a highly regulated system?
To PREVENT nonfunctional proteins being forwarded to the pathway for secretion or to other organelles.
What happens with proteins that cannot be folded or assembled properly by chaperones?
proteins undergo ER-associated degradation (ERAD), in which unsalvageable proteins are translocated back into the cytosol, conjugated to ubiquitin, and then degraded by proteasomes.