1. Contraction
2. Actin
3. Tendons
4. Epidermis
5. Dermis
6. Acne
7. A nerve signal from the brain arrives at the intersection of the nerve and muscle cells and releases acetylcholine from the neuron. This triggers chemical changes in the muscle cell involving ions, including Ca2+. Calcium triggers the thick filaments, made of myosin, to attach to the thin filaments, made of actin, in the muscle cell, and the myosin pulls the actin toward the center of the muscle cell. ATP causes the release of the actin fibers, allowing the muscle to relax and the process to begin again.
For Penn Foster.
Sickle cell anemia is a genetic condition that distorts the shape of the hemoglobin. This reduces the capacity of the red blood cells to carry oxygen. Another effect is that the distorted red blood cells come together forming a heavy and compact collection of cells that can block the flow of blood. The sedimentation rate is increased by sickle cell anemia.
Answer:
By changing a gene's instructions for making a protein, a mutation can cause the protein to malfunction or to be missing entirely. When a mutation alters a protein that plays a critical role in the body, it can disrupt normal development or cause a medical condition.
Answer:
C. hormone molecules
Explanation:
hormones are secreted in glands and are transported to the organs where they affect it and cause changes.
Answer:
Its either A or B
explanation:
pls give brainlyest