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
which cell stores fat?
adipose cells; 90% is fat, rest is nucleus that is pushed to the side
what cells are good for storing glycogen?
liver and muscle cells. this is because they require a lot of energy and dont want to have to wait for you to consume glucose
what is intermediary metabolism?
the chemical reactions inside the cell that involves the degradition, synthesis and transformation of small organic molecules such as simple sugars, amino acids and fatty acids
- the sum of all those reactions you’re breaking down a complex molecule into a simple one AND building a complex molecule from simple ones
what is it called when you break down a complex molecule into simple ones?
catabolic reactions
when working out, are you creating more muscle?
no, building muscle. number of muscle does not change. called hypertrophy. this is an anabolic process because you are taking something simple and making it bigger and complex. build up process
what is metabolism refering to?
- refers to building up, breaking down. anabolism and catabolism
where does intermediary metabolism occur?
in the cytosol
does intermediary metabolism involve enzymes and reactions?
yes, thousands
where is the energy in ATP stored?
in phosphate bonds
when is energy given from ATP?
energy comes from the bond holding the second and third inorganic phosphate together. so once the bond is broken, and ATP –> ADP, energy can be used.
- source of energy for the body is the chemical energy stored in the carbon bonds of ingested food
what type of bonds holds carbon bonds together?
covalent
when covalent bonds are broken, what is released?
energy
what is substrate level phosphorylation?
simply adding a phosphate group to ADP
why is it called oxidative phosphorylation?
because it uses oxygen. this is why we need to breath oxygen, so the process can work.
which process generates the most ATP?
oxidative phosphorylation
- is glycolysis anaerobic or aerobic?
- is it the first or second series of reactions of producing ATP production in oxidative phosphorylation?
- where does glycolysis occur?
- both. breathing or not. only step in breakdown of glucose that can occur without presence of oxygen
- first
- in the cytosol
how many ATP is produced without oxygen through glycolysis?
2 ATP
which system is used when generating ATP with substrate level phosphorylation?
creatine phosphate (CP) system
what is kinase?
an enzyme that phosphorylates. it takes a phosphate group and puts it with another one
what is creatine kinase?
the enzyme that would phosphorylate creatine using the phosphate from ATP
which energy system is used for when in need of fast energy when you have an adrenaline rush?
creatine phosphate
what is the waste of glucose after being broken down?
CO2
net ATP in glycolysis?
2 ATP
how many ATP in cellular respiration?
32 ATP (more or less but this professor says to answer with 32)
what is carbon broken into in glycolysis?
two, three carbon molecules called pyruvate. it then leaves the cytosol and goes into the mitochondria
2 pyruvates are transformed into what?
2 Acetyl-CoA in the citric acid cycle in the mitochondria
what are the carrier molecules?
NADH (10)
FADH2 (2)
what do the carrier molecules carry?
the high energy that was generated from breaking down glucose and take it into the mitochondria and go into the electron transport chain to donate their high energy electrons and hydrogen they’re carrying and then generate ATP
why cant the creatine phosphate system just make infinite ATP?
because it needs ADP in order to do substrate-level phosphorylation.
when the ATP is full, how does creatine make more? what enzyme is used?
creatine takes the high energy phosphate from ATP to create creatine phosphate. reaction is reversible. enzyme used: creatine kinase
what energy system is used for lifting muscles?
Creatine phosphate system
in the skeletal muscle, how much more creatine phosphate is stored than ATP?
5x more
