1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Mashutka [201]
3 years ago
6

When a muscle cell contracts, Group of answer choices the position of each myosin head is identical at any given moment. some my

osin heads bind to actin molecules as other myosin heads release from actin molecules. the myosin heads each produce a single power stroke. the intracellular calcium concentration remains unchanged.
Biology
1 answer:
White raven [17]3 years ago
3 0

Answer:

When a muscle cell contracts, the myosin heads each produce a single power stroke.

Explanation:

In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When the muscle fiber membrane depolarizes, the action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane and releases calcium into the sarcolemma. At this point, <em>tropomyosin is obstructing binding sites for myosin on the thin filament</em>. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin heads bind to the uncovered actin-binding sites forming cross-bridges, and while doing it ATP is transformed into ADP and inorganic phosphate which is liberated. Myofilaments slide impulsed by chemical energy collected in myosin heads, <u>producing a power stroke</u>. The power stroke initiates when the myosin cross-bridge binds to actin. As they slide, ADP molecules are released. A new ATP links to myosin heads and breaks the bindings to the actin filament.  Then ATP splits into ADP and phosphate, and the energy produced is accumulated in the myosin heads, which starts a new binding cycle to actin.  Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.

You might be interested in
What are the main functions of the skeletal system?
insens350 [35]
The skeletal system<span> performs vital </span>functions<span>— support, movement, protection, blood cell production, calcium storage and endocrine regulation — that enable us to survive.</span>
3 0
3 years ago
The ____________________ pattern of organization places several alternatives side by side and shows why yours is the best.
alexira [117]

The right option is d. comparative advantages

The comparative advantages pattern of organization places several alternatives side by side and show why one of them is more advantageous than the other. The items or alternatives to be compared are in relation to one another and are functionally equal.






7 0
3 years ago
When would a female have a 100% chance of inheriting a sex-linked trait?
Vladimir79 [104]

Answer:

C

Explanation:   Well C is usually correct for everything

:P

3 0
3 years ago
Which answer choice does not contain at least one cellular process inhibited by antibiotics?
USPshnik [31]
<span>Antibiotics work by selectively targeting the reproduction or growth of specific bacteria cells and by not attacking human DNA. Antibiotics do not, or should not, target and affect human DNA gyrases, although they should target the specific bacteria growth. The host, (human) DNA needs to remain unharmed while the bacteria does not replicate.</span>
5 0
3 years ago
Read 2 more answers
Blood is carried away from the heart to provide oxygen to rest of the body by the
LuckyWell [14K]
Tubes that lead from the heart to the rest bud
3 0
3 years ago
Read 2 more answers
Other questions:
  • The enzyme responsible for removing acetyl groups from histone proteins is called
    7·1 answer
  • Where are egg cells produced? (2 points)
    7·2 answers
  • Second growth timber refers to select one:
    7·1 answer
  • The properties and interaction of magnets are referred to as​
    12·1 answer
  • What is climacteric​
    15·1 answer
  • 1. A(n)<br> is the basic unit of matter.
    5·2 answers
  • Which should a scientist conclude about data that are inconsistent with the current, scientific understanding of amphibian repro
    6·1 answer
  • The plant cell wall __________.a. regulates the composition of the cytoplasm. b. is very similar to the animal cell wall. c. mak
    13·1 answer
  • It is possible for a repressor to negatively regulate the expression of an operon because: A. the repressor-binding site overlap
    12·1 answer
  • How many positive particles does zinc have? *
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!