Cell Structure Eu 2 Flashcards
How is the cytoplasm of a eukaryote divided?
The cytoplasm of eukaryotic cells is divided up into membrane-bound compartments called organelles.
What is the primary function of the plasma membrane in eukaryotic cells?
The plasma membrane surrounds all cells and controls the exchange of materials between the internal cell environment and the external environment.
What is the main structural component of the plasma membrane?
The fact that is it formed from a bilayer of phospholipids spanning a diameter of around 10nm.
What is the nucleus present it and what is it not?
The nucleus is present in all eukaryotic cells except for red blood cells.
What is the nucleus?
It is a large organelle that is separated from the cytoplasm by a double membrane (nuclear envelope) , which has many pores.
Why are nuclear probes important?
Because the nuclear pores provide important channels for allowing mRNA and ribosomes to travel out of the nucleus, as well as allowing enzymes and signalling molecules to travel in.
What does the nucleus contain?
The nucleus contains chromatin which is the material from which chromosomes are made.
What are chromosomes made of?
chromosomes are made of sections of linear DNA tightly would around proteins called histones.
Where is the rough endoplasmic reticulum found?
In plants and animal cells.
What is the surface of the rough endoplasmic reticulum covered in?
It is covered in 80S ribosomes.
How is the rough endoplasmic reticulum formed?
It is formed from folds of membrane continuous with the nuclear envelope. These flattened membrane sacs are called cistern.
What is the function of the rough endoplasmic reticulum?
-It processes the proteins made by the ribosomes.
What happens to the proteins synthesised by the ribosomes? How do they leave the cell?
The proteins synthesised by the ribosomes move to the cisternae, bud off into vesicles that carry the proteins to Golgi apparatus before being secreted out of the cell
What type of ribosomes are found in eukaryotes?
80S ribosomes
Where are the 80S ribosomes found in the cell?
They are found freely in the cytoplasm or as part of the rough endoplasmic reticulum in eukaryotic cells.
where are ribosomes constructed?
they are constructed in the nucleolus.
What is the function of ribosomes?
It is the site of translation, thus a part of protein synthesis.
What is the mitochondria the site of?
Mitochondria is the site of aerobic respiration within all eukaryotic cells.
With what are mitochondria visible?
Mitochondria are just visible with a light microscope.
What does the matrix produce?
The matrix contains enzymes needed for aerobic respiration, producing ATP.