Class Notes (1,100,000)
CA (620,000)
UTSG (50,000)
BIO (2,000)
Lecture 7

Lecture 7 - Movement.pdf

Course Code
Chris Garside

This preview shows pages 1-3. to view the full 22 pages of the document.
Movememtn can be created and produced in ways we may not
necesasrily think about. Not always made from mysoin / mucsle cells.
Lecture 7 - Movement
November 8, 2013
6:14 PM
BIO270 Page 1

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

All multicellular organisms can move, but animals are the only one who
can move from place to palce based on the myosins they are unique
because of the organization of the moelcules.. And use the muscle cells.
These components the actina dn motor proeins can be ofound within
the simple fungus as well. What really matters is the structural
organization the isoforms of the ones in the fungus , which have evoled
allowing the production of the superstructure , sarcoemre.
The 3D super structure allows us to really move to place to place. This is
really a cluster of tissues. Which allows us to eb envous of sme animals
like the cheetah. etc
Why is there originally a muscle protein? Why did they evolve? Why are
there so many different isoforms?
As animals grew larger the surface area to volume ratio is reduced.
Diffusion is no longer able to provide materials. They are required.
So you needed largfer animals to eveolve circulatory and
respiratory systems to give O2 all the body. Along with that you
required some compiudnand ,structure which could pump and
develop a force which could move those moelcules.
The movememnt os animal was knwn wa from water to land
stimulating evolution of these specific isoforms.
Therer are couple of reasons.
Should be envious of these
animals because of their
Q: skeletel muscle
Is striated.activated by a nerve impulse.
Have well developed tubules.
Skeleton muscles are multi nucleus and found on the periphery moslty
due to the fact that there are so many myofibres that the nucleus is
pushed to the periphery of the cell.
BIO270 Page 2

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Sketeon of the cell prividing structure and shape tp the cell.
There are so mant tracks of microtubules and microfilamets rhoguh out
the cell. They are polarized and have a + and - end. Vesicles move on
these cytoskelton tracks. Motor proteins that holds onto the vesicles
move in a specific direction. Cytoskelton netwerk is like a network of
roads. Determines where everything is going to go. We cant go without
a direction. Polarity gives direction.
Motor proteins: theya re enzymes , ATP ases most of the time.
Converte chemical --> mechanical energy
Kinesin and dyneine are the two primary tubules based motor protein
While myosin is the actin based microfilaments.
Kinesin moves rowatds the + end (remember that K looks like a plus
from the front without allignment K=+ ,) and dynenin moves towards
the - end. Mysoin moves towards the + end.
Directionality is given by the plarity
BIO270 Page 3
You're Reading a Preview

Unlock to view full version