Questions | 5 |
Topics | Arteries, Cell Division, Compound, Curved Lenses, Light Waves |
The aorta is the body's largest artery and receives blood from the pulmonary vein via the left ventricle. From there, blood is circulated through the rest of the body through smaller arteries called arterioles that branch out from the heart. Finally, blood is delivered to bodily tissues through capillaries.
Cell division is the process by which cells replicate genetic material in the nucleus. Cell division consists of several phases:
Phase | Major Process |
---|---|
interphase | chromosomes replicate into chromatids and the cell grows |
prophase | chromatids pair up |
metaphase | paired chromatids move to opposite sides of the cell |
anaphase | cell elongates and nucleus begins to separate |
telophase | separation of nucleus is complete resulting in two new nuclei |
cytokinesis | cytoplasm and cell membranes complete their separation resulting in two separate cells |
A compound is a substance containing two or more different chemical elements bound together by a chemical bond. In covalent compounds, electrons are shared between atoms. In ionic compounds, one atom borrows an electron from another atom resulting in two ions (electrically charged atoms) of opposite polarities that then become bonded electrostatically.
Unlike curved mirrors that operate on the principle of reflection, lenses utilize refraction. A convex lens is thicker in the middle than on the edges and converges light while a concave lens is thicker on the edges than in the middle and diffuses light. A common use for curved lenses is in eye glasses where a convex lens is used to correct farsightedness and a concave lens is used to correct nearsightedness.
Unlike mechanical sound waves that require a physical medium for propagation, light waves are electromagnetic and can travel through empty space. Light waves are also much faster, travelling at 186,000 m/s vs. 343 m/s for sound waves.