3) Because cardiac muscles are mechanically, chemically, and electrically connected to one another, cardiac muscle tissue functions like a single enormous muscle cell. For this reason, it is called a functional .

FUNCTIONAL SYNCYTIUM

Explanation: The cardiac muscles are the Pericardium (outermost), Myocardium (middle) and Endocardium (innermost) though three(3) in number but they work as a unit,this functional unit starts with the action of the pacemaker cells,the Sinoatrial nodes,Atrioventricular nodes, bundle of his,bundle branches/purkinjes fibers.

The contraction of the heart muscles relies on impulses from the nervous system and the contraction is coordinated and rapid inorder to bring about a uniform conduction of blood into, through and out of the heart.

humans, along with other animals and plants, have linear chromosomes that are arranged in pairs within the nucleus of the cell. the only human cells that do not contain pairs of chromosomes are reproductive cells, or gametes, which carry just one copy of each chromosome.

option a and d is the correct answer

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