Answer:
The tiles can be arranged as follows:
- make an observation
- ask questions
- construct a hypothesis
- test the hypothesis
- analyze the results and make conclusions
- communicate the result
Explanation
A scientific investigation begins with certain observations. By seeing these observations, a question is made. To answer the question, a hypothesis is generated. A hypothesis is a tentative statement that can either be stated s correct or wrong. To test the hypothesis, experiments are made and results are deduced from the experiments. Based on these results, a hypothesis can be proved as correct or wrong. These results are then communicated to check for their authenticity.
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:
peptide antigens by MHC class II molecules
Explanation:
Helper T cells are activated by peptide antigens by MHC class II molecules. These antigens express on the surface of antigen-presenting cells (APCs). After activation, the T helper cells divide and secrete cytokines to assist the immune response.