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:
the left handedness was a recessive trait and skipped one or maybe multiple generations
Explanation:
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Answer:
1. Klinefelter syndrome
2. Nobody can be born with a single X chromosome
Explanation:
1. A genetic condition in which a male is born with an extra copy of the X chromosome
Klinefelter's syndrome isn't inherited, but rather occurs only as a result of a random genetic error after conception.
Males born with Klinefelter's syndrome may have low testosterone and reduced muscle mass, facial hair and body hair. Most males with this condition produce little or no sperm,
2. Sex chromosome occurs due to combination of the X and Y chromosome of both parents.
This because ice is less dense than water of particular temperature range. Water reaches its maximum density at 4 degrees. Ice is important especially for aquatic life in the polar regions. Polar bears give birth and hunt on sea ice and they need it to travel from one region to another. The ice edge in coastal areas is an important feeding ground for the walrus that uses the ice as diving platforms to feed on clams on the sea floor. Ice algae grow at the porous bottom of sea ice and form the base of the unique marine food web connected to sea ice