The muscular system can be broken down into three types of muscles: skeletal, smooth and cardiac, according to the NIH. Skeletal muscles are the only voluntary muscle tissue in the human body and control every action that a person consciously performs. The muscle that is found at the heart is Cardiac Muscle. It is an involuntary, striated muscle that constitutes the main tissue of the walls of the heart. Hope this helps.
Answer:
Motor neurons:
A. Function:
It relay messages coming from the brain or spinal cord to the muscles or organs.
B. Structure:
●Presence of long axons due to long distances the signals have to travel to the muscle its stimulating.
●It's myelinated, to assist the signal in travelling long distances as soon as possible.
Sensory neurons:
A. Function: its sensory receptors respond to stimuli by converting it into an electrical signal to the brain or spinal cord.
B. Structure:
●Presence of long dendrites / axons
● its myelinated
●since it's found in the middle of the neuron it forms ganglia that unites in the spinal cord and aid in involuntary reflexes.
Interneurons:
Structure:
● shorter than motor or sensory neurons
● has branches, a lot of branches consisting of axons and dendrites off the cell body to enable multiple simultaneous between neurons
● It's body is partially myelinated.
●occurs in large clusters of neurons to compensate for its partial myelination to speed up the signal
Answer:
The answer is number two extinction happened, this was the time dinosaurs went extinct ebcause lack of sun because oh how much dirt was blown into the earth atmosphere becuase of the asteriod, third option is talking about big bang theroy so that dosnt apply!
Explanation:
The correct answer is:
D
.Villi in the small intestine have thin-walled capillaries to make the absorption of nutrients more efficient.
Explanation:
The small intestines are well adjusted for absorbing nutrients during digestion by being very long, having villi and microvilli that enlarge surface area, using muscular contractions to move and mix food, and raising and housing digestive enzymes and bile that aid the breakdown of food. The inner surface of the small intestine is not flat but thrown into circular folds, which not only enhance surface area but aid in preparing the ingesta by acting as baffles. Villi: the mucosa makes multitudes of ridges which project into the lumen and are satisfied with epithelial cells.