In cardiac muscle
a. an action potential spreads throughout the Z discs.
b. intercalated discs connect the muscle fibers together.
c. calcium enters the cell from storage chambers called intercalated discs.
d. potassium is released from the sarcoplasmic reticulum
Answer:
b. intercalated discs connect the muscle fibers together.
Explanation:
Intercalated discs are components of the muscles found in the heart(cardiac muscles).
Intercalated discs join the cardiomyoctes (muscle cells or fibers) together so that they can function as one and transmit signals amongst themselves during the contraction of the heart.
Intercalated discs are made of up desmosomes and gap junctions.
Intercalated discs are found on the lining of the sacromere and can only be seen by using a microscope to observe the longitudinal section of the heart tissue.
The Precambrian eon is separated from the Phanerozoic eon in the fossil record because of the sudden appearance of organisms.
Explanation:
Precambrian eon is the initial existence on earth that can be predicted by the study of rocks and remaining of fossils. It has been seen as the existence of skeleton in this era, before this era no such things has been observed, even the development of sexual reproduction.
The Phanerozoic era comes after the Precambrian era, more advanced kinds of fossils of animals had been observed in this era. Phanerozoic era period of life on earth. Large organisms sudden appearance are seen in the Phanerozoic era i.e. First dinosaurs, mammals, fishes, angiosperms,first vertebrates etc.
The answer would be B) Nitrogen Trioxide
Homeostasis is the maintenance of a relatively constant internal state. It is the process by which living organisms maintain a state of equilibrium in their internal environment. The organs that take part in homeostasis include: the skin, kidney and liver. These organs works together to maintain a stable internal environment.