Answer:
isometric contraction
Explanation:
An isometric contraction occurs as the muscle produces tension without changing the angle of a skeletal joint. Isometric contractions involve sarcomere shortening and increasing muscle tension, but do not move a load, as the force produced cannot overcome the resistance provided by the load.
Answer:
c. Spindle fibers
Explanation:
In eukaryotic cells, the centrioles are small sets of microtubules composed of tubulin proteins. Moreover, in animal cells, a centrosome is an organelle localized near the nucleus which contains a pair of centrioles. These organelles (centrosomes) are referred to as microtubule-organizing centers. During Anaphase, centrioles move to opposite sides in the cell in order to organize the spindle fibers and separate the chromosomes during cell division.
Answer;
Antibodies.
The human immune system fights infection by releasing antibodies.
Explanation;
The immune system acts to defend the body against pathogens such as viruses, bacteria and fungi that may cause a disease.
It does so using various types of mechanism, one is by the production of antibodies.
Antibodies are proteins that are produced by the B-cell and are used by the immune system to identify and neutralize pathogens.
These antibodies also activates proteins known as complements which assist in the killing of bacteria, viruses and the infected cells.