Hormone/protein production in a eukaryotic celll and the cytoskeleton Flashcards
Where is the specific instruction for making a hormone?
the instructions are in the DNA in the nucleus
the specific instructions is known as the gene for that hormone, the gene is on a chromosome
How is mRNA formed?
the nucleus copies the instruction in the DNA into a molecule called mRNA
How is the protein formed from the mRNA?
leaves through a nuclear pore and attaches to ribosome, which is attached to the the rough endoplasmic reticulum
the ribosome reads the instructions and uses the code to assembly the hormone (protein)
After the protein is formed, where is it transported?
the assembled protein inside the rough ER is pinched off in a vesicle and transported to the golgi appartatus
What does the golgi apparatus do to the protein and what happens after it leaves the golgi apparatus?
the golgi apparatus modifies and packages the protein so that it is ready to be secreted
it is then packaged into a vesicle and moved to the cell SURFACE membrane, where it is secreted
additional info:
the term cell membrane is too vague at a level as it could refer to any of the membranes within the cell
What are vesicles?
mebranous sacs that have storage and transport role, contains fluid
What is the function of the cytoskeleton?
throughout the cytoplasm of all eukaryotic cells, necessary for stability.
holds organelles in place and controls cell movement
What is the function of microfilaments?
microfilaments are contractile fibres formed from the protein actin, they are responsible for cell movement and contraction (cytokinesis - cytoplasm is divided to form two cells)
What is the function of microtubules?
globular tubulin proteins polymerise to form tubes, forms scaffolding like structures to control cell shape, form tracks for organelles
spindle fibres which segregate chromosomes in cell division is made from microtubules
What is the function of intermediate fibres?
give mechanical strength to cell and help maintain its integrity
Describe the roles of the cytoskeleton?
support cell
movement of cilia/flagella
change shape e.g. cytokenisis/phagocytosis/bulk transport/ muscle contraction
hold organelles in place / move them
movement of chromosome / mRNA
Outline how the organelles in the pancreatic cells work together to produce and release protease enzymes from the cells?
nucleus contains gene / is the site of transcription
ribosomes are site of translation
vesicles transport protein
golgi apparatus modified protein
vesicles fuse to the cell surface membrane to release the protein
