Answer:A. The release of calcium ions causes myosin and actin to attach to each other.
The contraction of skeletal muscles takes place by induction of a nerve impulse, which produces a movement and the interaction of the filaments containing proteins named as actin and myosin. This interaction of filaments is regulated by proteins called tropomyosin and troponin present on the actin filaments. The motor nerve causes the depolarization of the muscle membrane sarcolemma. This triggers the sarcoplasmic reticulum to release calcium ions. This calcium binds to troponin and thus allows the tropomyosine strand on the actin filament to displace so that the part of the actin where myosine head needs to be attached remain uncovered. Binding of the actin myosine filament results in contraction.
Hence, the release of calcium ions causes myosin and actin to attach to each other causes muscle contraction.
I believe it is a araebacteria
Answer:
Explanation:
This is because ferns are vascular plants i.e they have vascular tissues which are xylem and phloems which help to conduct water and nutrients while mosses are non vascular plants.
2. Ferns sporophytes are differentiated into true leaves, stems and true roots while mosses lack true roots, stems and leaves.
Underground stems are modified part of plants that are derived from stem tissues which grow under the ground. Underground stems grow beneath the soil. Examples include Rhizomes, ginger, tubers e t.c.
The property is called Adhesion
In short, because the UV rays damage skin cells, which increases the risk of a mutation possibly leading to skin cancer.
Hope this helps.
