Layer D is the oldest because bottom layers form first and are covered by new rock layers.
The correct answer is earthquakes
Answer:
Smooth muscle
Explanation:
- The smooth muscle is one of the three types of muscle present in the human body and other animals.
- The smooth muscle is called smooth because of its smooth appearance without any striations in its structure.
- The smooth muscle is made of the spindle-shaped cells characterized by a single nucleus.
- The smooth muscle cells are controlled by the autonomic nervous system and therefore is involuntary in its action.
The smooth muscle is present in the hollow organs and propels the substances through these hollow internal passages like in the alimentary canal of the digestive tract and urinary bladder.
Thus, the Smooth muscle is correct.
Plants’ nonspecific immune responses includes cell-surface receptors (pattern recognition proteins) which allow them to identify certain patterns characteristic for pathogens. Activated receptors trigger the production of chemical signals that may initiate both local and systemic defense responses. Sometimes when a plant is affected by infection, it triggers rapid localized programmed cell death to stop the infection further. When it comes to defense form the herbivores, plants have physical barriers (plant cell walls and their extensions), some antibiotic compounds (phytoalexins), and even enzymes that can defend them.