I think because they have a DNA
Answer:
Answer is Sinoatrial node, SA.
Explanation:
The sinoatrial node, SA, is known to be a group of cells which are found at the top of the heart.
The electrical signal that is initiated by the sinoatrial node bring about or stimulates the atria and then the ventricle of the heart.
It should be noted that, the sinoatrial node are regarded as the pacemaker cells.
Answer;
-Keratinized stratified squamous epithelium forms the epidermis of the skin.
-In keratinized stratified squamous epithelial tissue, the cells on the apical (outer) surface are dead.
Explanation;
-Stratified squamous epithelium is a type of tissue found covering and lining parts of the body. Stratified squamous epithelium may be keratinized or nonkeratinized. Non-keratinized surfaces must be kept moist by bodily secretions to prevent them from drying out.
-The cells on the surface of stratified squamous keratinized epithelium are very flat. Not only are they flat, but they are no longer alive. They have no nucleus or organelles. They are filled with a protein called keratin, which is what makes our skin waterproof.
Cell, and gas are for sure made up of atoms so it’s either heat or a solid
Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.