Eukaryotic cells do not have a nucleus. The nucleus is where DNA, your genetic material, is usually stored. Prokaryotic cells do not have a nucleus. The DNA just floats around the cell instead of staying in one designated area.
Sugar-phosphates and nucleotides
I think Autorhythmic fibers are fibers that are self excitable or on their own for example some cardiac muscle. They repeatedly generate action potentials that trigger heart contractions.They continue to stimulate a heart to beat even when it is removed from the body. In comparison to contractile fibers, autorhythmic fibers are self excitable and do not require nervous system stimulation to trigger contractions. Contractile fibers have stable resting membrane potentials of -90mV, when a contractile fibers reaches threshold by action potential, the voltage gated fast sodium ions channels will open.
Answer:
Option C.
Scientist explain the incomplete fossil record because not all organisms become fossils. Processes like erosion and mountain building can change rock layers, causing fossils to be spread over multiple layers or destroyed.
Explanation:
- Fossils are the remains of organisms that are found on the rocks after they die.
- So, no one can be 100% sure about the complete fossil record because of the continuous process like erosion and other natural calamities.
- The sediment must cover any organism's remains to start the fossilization process to start. Most of the organisms start decomposing before this process can be executed.
