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Flashcards in Biological Trends Improvement Deck (23):
1

Stretch of lung

Inhibits inspiration

2

Increase in CO2

Decrease in pH. Increase respiratory rate

3

Decrease in O2

Increase in respiratory rate

4

Where are peripheral chemoreceptors

Aorta and carotid arteries

5

What do peripheral chemoreceptors sense

CO2, pH, and O2 in blood

6

Where are central chemoreceptors?

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

7

Recombination Frequency

Number of recombinants/total number of offspring

8

What do myofibrils make up?

Myofibers

9

What do Myofibers make up?

Muscle fassicles

10

Sarcomere length

Z line to z line

11

Actin forms

Thin filaments

12

Myosin forms

Thick filaments

13

What is a sarcomere

Thick and thin filament

14

I bands only contain

Thin filaments

15

H zone only contains

Thick filaments

16

A bands are

Full lengths of thick filaments in H zone

17

What generates contraction

Actin and myosin

18

Length of I band

H zone to H zone

19

During contraction

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

20

4 steps to filament sliding theory

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.

21

What prevents contraction when Ca 2+ is not present

Troponin-Tropomyosin complex in the thin filament

22

Tropomyosin

Long protein winding around actin polymer blocking the myosin binding sites

23

Troponin

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