Sarcomere
There are no bright lines and no dark lines in the spectrum, incandescent light has a continuous spectrum with all visible colors present
absorption lines! :)
Visible light is defined as ALL frequencies in the range of 380 to 750 nm, and shows up as a smooth transition of colors like a rainbow when we split it up with a prism or diffraction grating. The spectrum of a star (like our Sun) contains (or is missing, depending on how you look at it) absorption lines that show up as dark lines in the spectrum. The link below has a very good visual comparison.
a spectroscope
We see the sun because of the light it shines and the light from it, travelling in straight lines, is going into our eyes allowing us to see it.
unit of alternating light and dark striations between z lines is a sarcomere.
Sarcomere
These are called striations.
Skeletal Muscle (as well as Cardiac Muscle) have striations do to their sarcomere's anatomy. The sarcomere is the functional unit of the muscle and appears striated because the different thick and thin filaments present.
The scratch marks left on the proyectile by the rifling lines of the inside of the bore (barrel).
In the sense that it makes it known that the rock existed before a period of glaciation, yes.
Power lines carry electricity as alternating current.
Striations are long, thin lines in the surface of something, usually multiple, and commonly all roughly or exactly parallel to each other. Picture dragging a stiff bristled floor broom across wet concrete - the marks it leaves behind are striations.
It is called an absorption spectrum.
Interlaced display is a type of cathode ray tube. The lines are in an alternating pattern that focuses on interwoven and rasterized lines.
alternating
The café wall illusion is a geometrical-optical illusion in which the parallel straight dividing lines between staggered rows with alternating black and white "bricks" appear to be sloped.