Answer: movement is always voluntary
Explanation:
Muscles are contractile:
- Contractility is the ability of muscle cells to forcefully shorten. Think of having the ability to flex a muscle.
Muscles are excitable:
- Excitable tissue can conduct or transmit electrical impulses. Basically, it can react to stimulus, which may be delivered from a motor neuron or a hormone. For example, the hormone epinephrine helps muscles to produce force.
Muscles respond to stimulus:
- well since muscles are an excitable tissue, they can react to stimulus. (see answer above)
————————
Muscle movement is NOT always voluntary:
- Some muscle movement is voluntary, which means it is under conscious control. For example, a person decides to open a book and read. Other movements are involuntary, meaning they are not under conscious control, such as the contraction of your pupil in bright light, breathing, blinking, your heart beating, etc.
- Therefore, the correct answer is:
movement is always voluntary
hope this helps :)
Answer:
The cell wall is a fully permeable membrane while as the plasma membrane is a particular membrane
Explanation:
The cell wall will allow all the substances go inside or outside while as the plasma membrane will only allow certain substances to go in or out based on the cell's needs.
Flatworms (Platyhelminthes) are phylum of unsegmented, soft, flat invertebrates.
Flatworms have no body cavity which is why they are flat. The advantage of a flat body is facilitated respiration and circulation. Flatworms do not have respiration and circulation system. But, oxygen diffuses across the skin and reach all parts of the body thanks to a flattened shape. Also, it is easy to hide from predators because they can get almost everywhere thanks to the body shape.
