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
Flowering plants are the most successful land plants because theri seeds are protected in fruits
Ribosomes process proteins that the cells need just like the softball team process the information that the coach give them in order to win.
Answer:
A. dihybrid crosses
Explanation:
A dihybrid cross can be defined as a mating experiment between two lines/varieties/organisms that differ in two phenotypic traits. By using pea plants, Mendel performed dihybrid crosses in order to analyze the mode of inheritance of both phenotypic traits at the same time. From these mating experiments, Mendel observed that the inheritance factors (nowadays called genes) sorted independently from one another in the next generation, which is called the principle/law of Independent Assortment.
DNA.
DNA has a phosphate and deoxyribose sugar backbone.
