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<u>cardic muscles:</u> are present only in the heart .single cell is not very strong by itself, millions of cardiac muscle cells working together are easily able to pump all of the blood in the body through the heart in less than a minute. Cardiac muscle cells have a branched shape so that each cell is in contact with three of four other cardiac muscle cells.
<u>characteristics of cardic muscles: </u> one nucleus ,striated, involuntary, branched and joined to one another by intercalated discs that contain gap junctions for depolarization between cells and hold the fibers together when the heart contracts.
Answer:
300,000 years ago
Explanation:
Homo sapiens evolved from their early hominid predecessors between 200,000 and 300,000 years ago and developed a capacity for language about 50,000 years ago.
Proteins are made up of 20 different amino acids
Answer:
This voice box occurs in all amphibians but is anatomically most complex in frogs. The larynx exits into the trachea; the latter bifurcates into the bronchi and then into the lungs. The glottis then opens, and elastic recoil of the lungs forces the pulmonary air out and over the new air in the buccopharyngeal pocket.
Explanation:
