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:
Explanation:
Gas exchange occurs at the alveoli in the lungs and takes place by diffusion. The alveoli are surrounded by capillaries so oxygen and carbon dioxide diffuse between the air in the alveoli and the blood in the capillaries.
a. Sugar cane, corn, carbgrass which are identified as C4 Plants allow fixation of carbon dioxide into four carbon compounds. This happens during the hottest time of the day - their so-called stomata gets partially closed. C4 plants have been identified to lose only half of the water that C3 plants lose when they produce the similar amount of carbs.
<span>b.CAM PATHWAY - Plants such as pineapples and cactus have different approach to adapting heat. Carbon is fixed through a cam pathway. They use it to open their stomata at night and close it in the morning.</span>
The answer would be c i think hope i could help
The forelimbs of all mammals are homologous traits, meaning that they originate from a common ancestral trait.
The correct answer is therefore C. Homologies (homologous traits), from the same common ancestor.
(To clarify, we know it is from a common ancestor because both bats and humans are mammals)
