Sponges have specialized cells and an endoskeleton, but they lack tissues and body symmetry. ... They include jellyfish and corals, both of which have radial symmetry. All cnidarians have nematocysts, and many are bioluminescent. They may exist in medusa and/or polyp form.
Answer:
When the frequency of stimulation of a muscle increases -without it having the opportunity to relax- a process called summation (addition) occurs, promoting an increase in the generation of force in the isolated skeletal muscle.
Explanation:
Summation is a phenomenon that occurs as a consequence of the arrival of successive stimuli that produce the contraction of the skeletal muscle before it achieves its partial or total relaxation, between subsequent stimuli.
<em>When the summation occurs in the muscle, the force generated on it increases its magnitude proportionally to the number of stimuli received, maintaining the muscle contraction in time</em>.
Tetany is the prolonged contraction of a muscle in an abnormal way, by the summation of stimuli received , as some bacterial toxins can produce. The summation can be temporary -when multiple stimuli reach the muscle in a determined time- or spatial, when the amount of stimuli activates a greater amount of motor units.
Learn more:
Spatial summation in a post synaptic neuron brainly.com/question/9632682
Answer:
Aa
Explanation:
The dominant gene is purple and usually represented with the capital letter while the recessive gene is white
Answer:
The half-life of a substance is the amount of time it takes for half of that substance to decay. However, after two half-lives, half of the half remaining will decay, leaving you with one quarter of the original substance.
So, after 1 million years you will have 50% of the original substance remaining.
And, after 2 million years you will have 25% of the original substance remaining.
After 3 million years you will have 12.5% of the original substance remaining.
And after 4 million years you will have 6.25% of the original substance remaining.
Explanation:
Hope it helps:)
Hox genes are also called Homeotic genes. In which they act as dictators on specific areas of an organism's body on when or where it should be developed. When these genes are overactivated or inactivated it may cause genetic disorders.