Answer: A Microtubules
Explanation: The cytoskeleton is composed of at last three different types of fibers: microtubules, microfilaments, and intermediate filaments. These fibers are distinguished by their size with microtubules being the thickest and microfilaments being the thinnest.
Answer:
A frogs heart has 3 chambers. Two atria and a single ventricle.
Answer:
b. Synergistic dominance
Explanation:
The stabilizing muscles will always be <u>synergistic</u>, since only from the synergies (hence the term synergist) that arise from joint work is efficient and controlled movement possible. However, not all synergists will be stabilizers. Stabilizer will be one that, thanks to the geometric arrangement of its fibers, will have the ability to maintain alignment in the joint and stable the axis of rotation.
In the case of knee extension, we would have as stabilizers all the antagonists who, because the flexion axis is virtual and not physical, must maintain the stability of said axis. If the axle were physical, such as the wheel in a horse carriage, or on a skateboard through the bearings, the antagonistic muscles would not be necessary for this purpose, because the fixed axis would maintain the position. Since the joints of living beings do not have a fixed physical axis, it is the muscles themselves, specifically the antagonists, who must be responsible for maintaining the stability of the joint creating a virtual axis on which rotation occurs.
An example of a population in which evolution could take place in a relatively short period of time could be pathogenic bacteria exposed to antibiotics.
Answer: Option A
<u>Explanation:</u>
Evolution if takes place within a short period of time say the next generation that is called as micro evolution. This is caused when a specific organism exposed in a different environment at once modifies its genes to suit the new environment. This phenomenon can be very well seen in the pathogenic bacteria which are exposed to antibiotics.
When an antibiotic is prescribed to bacteria initially it nullifies its effect by destroying it. When continuously exposed to a certain antibiotic some bacteria dies but there are few which becomes resistant to it and survives. This on the other hand multiplies producing a generation that can’t be touched by the antibiotic.
