Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis.[1][2][3] Nondisjunction results in daughter cells with abnormal chromosome numbers (aneuploidy).
Calvin Bridges and Thomas Hunt Morgan are credited with discovering nondisjunction in Drosophila melanogaster sex chromosomes in the spring of 1910, while working in the Zoological Laboratory of Columbia University.[4]
Answer:
Yes
Explanation:
A phase change does not change the chemical make-up of a substance. Phase changes are typically temperature dependent, and change only the movement and physical arrangement of the atoms and molecules in the substance. Water, for example, is composed of two hydrogen atoms attached to an oxygen atom by covalent bonds. That stays the same whether the water is solid (ice), liquid (water), or gas (steam). The chemical structure of water does not change as it goes through the different faces. It's still water. What does change is the speed at which the molecules move and how far apart they are as a result. Water vapor consists of molecules moving quickly and at random. As temperature drops, water molecules slow down. Since water is slightly polar, hydrogen bonds form between the molecules bringing them closer together.
Answer:
Either B) increased parasympathetic stimulation of the heart. OR D) Constriction of elastic arteries to maintain blood pressure. I'm leaning more towards D) constriction of elastic arteries to maintain blood pressure.
Answer:
Nitrogen thet cannot be used by organisms. C.
Explanation:
Free nitrogen is simply molecular nitrogen (N2). Nitrogen, in its molecular form, consists of two nitrogen atoms bound together with a tripple bond. Because it is very stable, N2 is typically nonreactive, and takes a lot of energy to break them apart. Among these are the amino acids necessary for life to begin and which are the building blocks DNA is made from. Basically, any nitrogen that is in an organic compound is considered “fixed” nitrogen and N2 is considered to be “free” nitrogen
The U.S. has one of the highest, if not, the highest obesity rate in the world.
