Myofibrils are the building blocks or contractile unit of each muscle fiber. The tiniest functional unit of skeletal muscle, the sarcomere, is found in the myofibrils and is made up of protein filaments: actin (thin) and myosin (thick).
Answer:
The statement is false.
Explanation:
Epinephrine (also known as adrenaline) is a hormone and a neurotransmitter produced by the adrenal glands, it helps to regulate cellular energy metabolism and increases the heart rate.
Epinephrine adheres to certain receptors that are exposed on the surface of a large number of body cells. This receptor, called beta-adrenergic, is a receptor that is embedded in the plasma membranes of these cells. Adrenaline does not penetrate the cell, instead, joining for a short period of time to its receptor, induces it to release biochemical signals to the cytoplasm of cells. This steric change, affects the configuration of the cytoplasmic domain of the protein, this is the "link" of the receptor that protrudes in the cytoplasm.
In general, the function of the excretory system is, removal of nitrogen waste products from the bloodstream and transport out of the body through urine. It maintains the balance of fluids and electrolytes, control of red blood cells, regulation of blood pressure and also the formation of red bone marrow.
In humans, the excretory system is responsible for removing waste from the body. Metabolic waste is being removed from the blood and an appropriate amount of water nutrients and water and salt are being retained.
In frogs, the excretory system consists of a pair of ureters, kidney pairs, cloaca, and urinary bladder. Frogs take in liquid waste from kidney which removes wastes and then the extra water becomes urine which then it is collected in the urinary bladder through ureters.
The urinary bladder is present in ventral to return then both open into the cloaca.
Most organisms rely on the sun as a primary source of energy
