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Answer:</h2>
<u>A. The concentration of calcium in the myofibril must decrease.
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<h2>
Explanation:</h2>
Each time we move a muscle, it requires the joined activity of trillions of myosin engines. Our muscle cells use calcium particles to facilitate this monstrous atomic exertion. At the point when a muscle cell is given the sign to contract from its related nerves, it discharges a surge of calcium particles from an uncommon intracellular holder, the sarcoplasmic reticulum that encompasses the groups of actin and myosin fibers.
The calcium particles quickly spread and tie to Tropomyosin on the actin fibers. They move shape somewhat and enable myosin to tie and start moving up the fiber. These trillions of myosin engines will keep climbing, getting the muscle, until the calcium is evacuated.
The calcium pump enables muscles to relax after this furious flood of calcium-instigated constriction. The siphon is found in the film of the sarcoplasmic reticulum.
Para realizar la fotosíntesis las plantas necesitan varios elementos que se encuentran en el medio ambiente.
Energía luminosa: impacta sobre las hojas y es absorbida por el pigmento fotosensible de la planta, la clorofila.
Agua: La fotosíntesis requiere un suministro constante de agua. Ésta llega a las hojas a través de las raíces y tallos.
Clorofila: Pigmento de color verde contenido en el cloroplasto. Se encarga de la absorción de la luz, para llevar a cabo la fotosíntesis.
Dióxido de carbono: Es absorbido por unos minúsculos poros, llamados estomas, en la parte inferior de la hoja.
Oxígeno: subproducto de la fotosíntesis. Sale de las hojas hacia el exterior a través de lasestomas.
<h2>
Answer:</h2>
Option C) The organism can move around its environment using a flagellum.
<h2>
Explanation:</h2>
Out of four options option C) matches the most.
- Although most of the bacteria are Heterotrophs but a variety of species of them are Autotrophs making their own food. Hence option a) is incorrect.
- Bacteria belong to prokaryotes which means they do not have a well defined membrane bound nucleus. hence option b) is also incorrect.
- Most of the bacteria can move through flagella only a few species do not have flagella. Hence this option matches the most.
- Bacteria are unicellular organism and none of the species of bacteria is multicellular. Hence option d) is incorrect.
Resut: Option C) matches the most for defining bacteria.
Answer:
In hypertonic solutions, the cells will shrink and in hypotonic solutions the cells will fill up
Cells with cell walls will be able to control their tonicity better than cells without cell walls.
Explanation:
Cells with cell walls
- In a hypertonic solution (high solute concentration), water will flow out of the cell into the solution until equilibrium is reached. If the solution has a high concentration of solute the cell may undergo<u> plasmolysis where the plasma membrane detaches from the cell wall.</u>
- In a hypotonic solution: Water will flow into the cell because it has a higher solute concentration compared to the solution. This will continue until the cell is <u>turgid</u>. If more water continues to enter the cell, the cell is at risk of bursting, this takes a while because the cell wall will withstand the pressure.
Cells without cell walls
- In a hypertonic solution: Water will diffuse out of the cell, however there is no cell wall so cell is in danger of shrinking and dying.
- In hypotonic solution: Water will diffuse into cell,the cell will become turgid and if water keeps moving in the cell will burst because it has no cell wall to resist the pressure.
