Module 1: Lecture 2 Flashcards
what is the cytoskeleton and what is it used for?
- it is the “bone and muscle” of the cell
- allows the cell to hold shape, structure and do movement
what is a miccrotubule?
a cytoskeletal protein
- a long cylinder made of tubulin protein
what do microtubules do?
all the cell to hold a specific shape
- function as “molecular highways”
- transport something from one place to another
- assemble into mitotic spindle
what positions cytoplasmic organelles (like the ER, Golgi complex, lysosomes and mitochondria) into their proper place?
microtubules
what is the largest and smallest cytoskeletal proteins?
largest: microtubules
smallest: microfilaments
are actin and myosin microtubules or microfilaments?
microfilaments
what is actin microfilaments and myosin filaments made up of?
- actin microfilaments are made up of actin subunits
- myosin microfilaments are made up of myosin subunits
what do we need actin and myosin for?
movement
- most abundant (common) in muscle cells because they are always contracting
- certain white blood cells and fibroblasts
where is microvilli?
in the small intestine
why do we make cytoplasmic projections?
to increase surface area
why do we want to increase surface area of the intestine by making cytoplasmic projetcions?
to increase absorption
what holds structure of microvilli? especially against all the fluid in the intestine?
microfilaments
what does an intermediate filament look like?
- the pull apart twizzlers
- rope-like
- teeny strands all put together and twisted
because an intermediate filament is made up of many teeny strands all put together and twisted, it makes it hard to break. what may this be good for?
resisting pressure
- helps resist mechanical stress
- this is what allows our skin to not pull apart
Intermediate filaments are most present in which cells?
skin cells, lung cells, heart cells, muscle cells
- good because each need to be stretched and expand
is intermediate filaments only present in cells?
no, can also be present in certain types of proteins that the cells make, like hair and nails, keratin
what are the three types of cytoskeletal protein?
- microtubules
- microfilaments
- intermediate filaments
what is the cytosol?
the cell gel
- water, enzymes, vesicles and inclusions
what are the intermediary metabolism enzymes?
the enzymes in the cytosol that are used to break down or make something (metabolic process)
what are the transport, secretory and endocytic vesicles?
the vesicles in the cytosol that transports or stores products being moved within, out, or in the cell
what are inclusions?
deposits of things we want to store. stores glucose in the form of glycogen and stores fat droplets