lecture 16

Question 1

what can’t skeletal muscles do

Answer 1

• the skeletal muscles can’t really do anything unless spanning to something or attaching to it. The attachment point will determine the muscles action, or what it will do when it contracts

Question 2

origin

Answer 2

the immovable/less moveable attachment point.
* Is the anchor for the muscle. Is a stable attachment point during contraction that either does not move at all or moves very little.

Question 3

insertion

Answer 3

the attachment to the moveable bone.
* When contraction occurs, it pulls the insertion point towards the origin point.

Question 4

prime mover (agonist)

Answer 4

The muscle that is primarily responsible for a particular movement
* Ex: during abduction of the shoulder the deltoid is the prime mover. In adduction there would need to be something working in opposition to the deltoid.

Question 5

antagonist

Answer 5

A muscle that works in opposition to the agonist. Typically, it is on the opposite side of the joint from the agonist.
* Ex: the Teres Major muscles are the antagonist. It works against the deltoid muscle to help in the process of should adduction.

Question 6

synergist

Answer 6

These muscles work together alongside the agonist to help perform a movement.
* Ex: the supraspinatus is a synergist for the deltoid in should abduction.

Question 7

isometric

Answer 7

there is muscle tension, but it has no change in muscle length. This is what happens when the muscle is not able to overcome the load.

Question 8

isotonic

Answer 8

the muscle shortens in length because it can overcome the load. The sliding of the filaments occurs allowing the sections to slide over each other.

Question 9

identify the stages of muscle contraction processes that require ATP

Answer 9

• Cross-bridge contraction (ATP is needed to allow for myosin to attach and pull on actin. Also to make myosin detach from actin.)
• The power stroke (when ATP allows myosin to detach from actin after pulling on it)
• The sodium - potassium pumps
• Sarcoplasmic reticulum – the calcium has to be removed by ATP to do muscle contraction, and then ATP has to move calcium against the concentration gradient and back into the sarcoplasmic reticulum.

Question 10

direct phosphorylation

Answer 10

is the act of covalently linking a phosphate group onto a molecule. When the ATP is used up, it hydrolyzes into ADP +Pi and then to later regenerate ATP, we must phosphorylate ADP. Essentially removing the group by separation, then adding it back in to recreate the original stage.
- linking ADP + Pi, not good as a long term solution, can last about 15 seconds

Question 11

aerobic respiration

Answer 11

it occurs inside the mitochondria and requires the use of oxygen. This can continue for as long as there is oxygen and a fuel source. Cells that require a lot of ATP or energy will have a lot of mitochondria to allow for a lot of aerobic respiration.
* For each response we release 32 ATP per glucose. Releases carbon dioxide and water

Question 12

anaerobic glycolysis

Answer 12

this is a type of reaction that does not require the use of oxygen but needs the use of ATP to occur. It can provide enough ATP for reactions to last for 30-40 seconds. Lactic acid is produced in these processes.
* We produce 2 ATP per cycle and the byproduct is lactic acid.

Question 13

identify the byproduct of direct phosphorylation

Answer 13

creatine phosphate
- Which is a high-energy molecule that is stored in muscles that can be used to regenerate ATP. This is a limited thing and can only provide maximal muscle power for around 15 seconds.

Question 14

the byproduct of aerobic respiration

Answer 14

carbon dioxide and water

Question 15

the byproduct of anaerobic glycolysis

Answer 15

lactic acid

Question 16

Describe the efficiency of ATP production in aerobic vs. anaerobic conditions

Answer 16

• ATP production is much more efficient in aerobic conditions. In an aerobic condition the body produces 32 ATP, while with anaerobic there is a production of 2 ATPs.