Answer:
The prolonged electrical depolarization of cardiac muscle cells -that occurs during contraction- is due primarily to the persistent influx of calcium ion
Explanation:
The action potential of the heart muscle is longer with respect to skeletal muscle (around 300 milliseconds), and this is due to the activity of calcium (Ca⁺⁺ ) in the intracellular compartment.
The initial depolarization of cardiac muscle fiber depends on the entry of sodium (Na⁺) into the cell. However, for the action potential to occur and be maintained, Ca⁺⁺ must increase its cytoplasmic levels, which depends on:
- The increase in intracellular sodium induces the release of Ca⁺⁺ from the sarcoplasmic reticulum.
- Calcium entry from the extracellular space through the voltage dependent Ca⁺⁺ channels.
- The entry of extracellular Ca⁺⁺ causes the release of more Ca⁺⁺ ions by the sarcoplasmic reticulum, further increasing its intracellular concentration.
This is how the ion that guarantees the duration of the action potential of the cardiac muscle cell is the Ca⁺⁺.
Learn more:
Calcium, sodium and cardiac muscle cells brainly.com/question/4473795
Answer:
My guess would be H₂O/ water, since osmosis is a form of passive transport and I can't see the model the question references. Gases like O₂/ oxygen, CO₂/ carbon dioxide, and simple sugars like glucose can also pass through a cell membrane with passive transport though.
Natural gas
explanation:
solar power, coal, and petroleum are used to power things (i.e. produce electricity)
Answer:
It's B
Explanation:
Law of independent assortment stated that individual heredity factors assort independently during gamete production. the evidence that Mendel find that supported his law of independent assortment is : different traits are passed on independently of each other
Answer:
c. Proteins
Explanation:
A stretch of DNA that code for specific proteins is said to be a gene. A gene is transcribed into mRNA. The mRNA has a nucleotide sequence complementary to the corresponding gene. The nucleotide sequence of mRNA is read in the form of genetic codes during the process of protein synthesis to specify the amino acid sequence of proteins. Therefore, genes carry the genetic information for the assembly of proteins and the processes of transcription and translation deliver the stored genetic information.
