Fundamental features of eukaryotic cells Flashcards
What are the fundamental features of a eukaryotic cell that you don’t see in prokaryotic cells?
Membranes provide compartments for processes inside the cell
What is the main method of reproduction in Prokaryotes?
Binary fission, mostly asexual
What is the main method of reproduction in Eukaryotes?
Mitosis or meiosis, mostly sexual
What function does compartmentation in the cell serve?
Differences in pH across the membrane inside the cell
Metabolic regulations by keeping enzymes/substrate separate
Isolate toxic substances
What affect does SA:V ration have on a cell?
limits the rate of exchange
Why are cells small?
Need to be able to communicate with the environment, and quick communication within the cell.
What is a coenocyte?
Large cell with multiple nuclei and chloroplast.
What are the main components of the Plasma membrane?
bilayer of phospholipids, with various proteins embedded
What makes up a phospholipid?
hydrophilic phosphate head, glycerol molecule and hydrophobic two fatty acid tails.
What is an amphiphatic molecule?
Has both hydrophilic and hydrophobic parts (polar and non polar)
What is contained within the nucleus?
Most of the genes contained within a eukaryotic cell
Describe the membrane around the nucleus
Is an envelope, perpetuated by pore structures which are lined by protein complexes that regulate entry and exit of materials.
How is DNA organised in the nucleus?
In chromosomes, which are made of chromatin.
How many chromosomes does a human have?
46
What processes take place within the nucleus?
Synthesis of mRNA with the instructions provided by the DNA.
What does the Endoplasmic Reticulum consist of?
network of membranes and tubules called cisternae, connected to the nuclear envelope
What is the role of the SER?
varies within cell type, lots of metabolic processes, e.g.. synthesis of lipids, modification of carbs and detoxification of drugs and poisons
What is different about the RER and SER?
RER has bound ribosomes
How do proteins leave the ER?
In vesicles
What is the name for vesicles in transit?
Transport vesicles
What are the roles of the ER?
protein processing, phospholipid production and membrane production
How is the RER a membrane making factory?
It grows in place by adding membrane proteins and phospholipids to its own membrane.
What is the role of the Golgi apparatus?
centre of manufacturing, modification, sorting and shipping
What is the structure of the golgi apparatus?
flattened membrane sacs, cisternae, all staked up.