Solution
Cut open an onion.
Use forceps to peel a thin layer of epidermis from the inside.
Lay the layer of epidermis on a microscope slide.
Add a drop of iodine solution to the layer.
Carefully place a coverslip over the layer.
Observe it under a microscope to see onion cells.
4. When you look up to the sky, it appears as a dark circle with halo light at its edges moving across the face of the sun. As it does, depending on the relative position of the person on earth – that determines where they are on the umbra or penumbra of the eclipse, the place becomes a daytime twilight (umbra) or partial twilight (penumbra).
5. A new moon is formed when the moon is in between the sun and the earth. This is converse to the case of a lunar eclipse where the earth is between the sun and moon. In a new moon, the face of the moon that is faced towards the earth is dark because it is not lit by the sun. It is important to note that a solar eclipse is not formed because the moon’s orbit, around the earth, is tilted at an angle.
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:
Soap is a basic
Explanation:
Soap is a combination of a weak acid (fatty acids) and a strong base (lye), which results in what is known as “alkalai salt,” or a salt that is basic on the pH scale.
The chemical reactions in the cell would not happen as fast and would require more energy to catalyze the reaction between the two reactants.
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Chemistry/ Example: Take breathing for example, when you breath you breath out carbon dioxide. The CO2 can't just leave like that and only 10% binds to hemoglobin. The rest turns into carbonic acid in your blood and its plasma. However, the acid is unstable, so it turns into bicarbonate and a dissociated proton (H). You have carbonic anhydrase that converts the two so you can breath out CO2; the carbonic acid separates into H2O and CO2. This process would take a LONG time without the enzyme-- CO2 build up, even minimal amounts it lethal.