Lecture Set 2 Flashcards
What do all cells have?
Plasma membrane, nucleus, cytoplasm
What are the two types of membranes?
Plasma –> separate inside from outside
Internal –> compartmentalize, separate organelles
What limits the size of the cell?
Minimum –> biomolecules needed for existence
Maximum –> rate of diffusion through cytoplasm
What is the function of the membrane
1) increase SA
2) maintain integrity/structure of cell/organelles
3) Present highly selective permeable barrier –> create concentration gradients
4) Works with signalling –> receptors, generation of chemical/electrical signals
5) energy transformation –> mitochondrial membrane
Describe nucleus
Has nuclear envelope (2 membranes contiguous with ER)
has nuclear pores
has nucleolus –> site of rRNA synthesis, ribosome production
Describe the mitochondria
double membrane, cristae (folds), matrix (inner space)
performs cellular respiration, electron transport, oxidative phosphorylation
Describe the ER
smooth –> no ribosomes, lipid and sterol production
rough –> dotted with ribosomes –> protein synthesis, membrane proteins, oligosaccharides
Describe the Golgi
sorting, post-translational processing
What is the function of glycosylation
helps with sorting
very rigid, provides steric interactions to prevent other molecules from approaching
serve as recognition molecules
act as regulatory role
Created by adding carb to surface bound protein/lipid
what is a lysosome and peroxisome
lysosome –> hydrolytic enzymes
peroxisome –> oxidases that produce hydrogen peroxide used by catalase to break down toxic substances
What is the ECM?
extracellular matrix –> proteins/polysaccharides secreted into extracellular space
Whats the difference between nucleoid and nucleus?
nucleoid = cytoplasmic mass of DNA not in a membrane
nucleus - DNA contained within membrane-bound structure