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.
Answer: reading paper books and magazines, sleeping in beds under cotton sheets, having a sandwich for lunch
, sitting at wooden desks
, I picking wildflowers
, eating a favorite breakfast cereal.
Explanation: These are all correct because each has to deal with plants. For example, reading the paper books, sleeping in the bed and sitting at the wooden desk all have to due with the products that come from plants. Paper, cotton, and wood are all grown from plants and turned into resources. Next picking flowers, eating foods are also direct examples of how plants help us. Picking flowers that come directly from plants. Then eating food that is grown from plants shows that it is directly plants providing for humans.
Answer: The student get full credit for attending the field trip. Submitting trip evaluation is optional.
Explanation:
I believe the blank would be the dirt soil