The environment includes abiotic (nonliving) and biotic (living) factors. An ecosystem consists of all the biotic and abiotic factors in an area and their interactions
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.
1. The separation of a substance into simpler substances or basic elements. 2. The process of decaying or rotting. Decomposition of dead organic matter is brought about by the activity of certain bacteria and fungi feeding on it.
Answer: That a STD is not contagious but can be given by blood bond in other words like if you kiss someone and they have blood on there lip or a sore you can get it like that or if you have finger to finger for example holding hands and they have a little wound there would be a 57% chance they would get the STD. Hopes this helps!
Explanation: