Biological Trends Improvement

Question 1

Stretch of lung

Answer 1

Inhibits inspiration

Question 2

Increase in CO2

Answer 2

Decrease in pH. Increase respiratory rate

Question 3

Decrease in O2

Answer 3

Increase in respiratory rate

Question 4

Where are peripheral chemoreceptors

Answer 4

Aorta and carotid arteries

Question 5

What do peripheral chemoreceptors sense

Answer 5

CO2, pH, and O2 in blood

Question 6

Where are central chemoreceptors?

Answer 6

Medullary respiratory control center. Monitor CO2 and pH of the CSF

Question 7

Recombination Frequency

Answer 7

Number of recombinants/total number of offspring

Question 8

What do myofibrils make up?

Answer 8

Myofibers

Question 9

What do Myofibers make up?

Answer 9

Muscle fassicles

Question 10

Sarcomere length

Answer 10

Z line to z line

Question 11

Actin forms

Answer 11

Thin filaments

Question 12

Myosin forms

Answer 12

Thick filaments

Question 13

What is a sarcomere

Answer 13

Thick and thin filament

Question 14

I bands only contain

Answer 14

Thin filaments

Question 15

H zone only contains

Answer 15

Thick filaments

Question 16

A bands are

Answer 16

Full lengths of thick filaments in H zone

Question 17

What generates contraction

Answer 17

Actin and myosin

Question 18

Length of I band

Answer 18

H zone to H zone

Question 19

During contraction

Answer 19

Z lines shorten, Myosin uses ATP, myosin head attaches to myosin binding site on actin. Contraction occurs when myosin head is cocked

Question 20

4 steps to filament sliding theory

Answer 20

Myosin head binds to actin with ADP and Pi bound, power stroke occurs with myosin head moving to low energy conformation pulls actin toward center of sarcomere. ADP released. Binding of ATP needed necessary for release of actin by myosin. ATP hydrolysis occurs immediately and myosin head is cocked into a high energy confirmation.

Question 21

What prevents contraction when Ca 2+ is not present

Answer 21

Troponin-Tropomyosin complex in the thin filament

Question 22

Tropomyosin

Answer 22

Long protein winding around actin polymer blocking the myosin binding sites

Question 23

Troponin

Answer 23

Globular protein bound to Tropomyosin that can bind Ca2+. When undergoing conformational change it is bound to Ca that moves Tropomyosin so that myosin binding site exposed