The backbone of DNA and RNA is composed of sugar and phosphate.
DNA is double stranded due to interactions between adenine, cytosine, guanine, and thymine, which are nitrogenous bases.
Uracil is a nitrogenous base that is only used with RNA.
Answer:
Courtney is looking at Prokaryotic Cell.
Explanation:
Ok, when Courtney is observing the science experiment, and finds a cell that includes DNA and has a nucleoid region but does not have nucleus, it is a prokaryotic cell and only the single-celled organisms of the domains Bacteria and Archaea are classified as prokaryotes, where pro means before and kary means nucleus.
Let's explain what is a prokaryotic cell: prokaryotes are unicellular organisms that lack organelles or other internal membrane-bound structures. Therefore, they do not have a nucleus, but, instead, generally have a single chromosome: a piece of circular, double-stranded DNA located in an area of the cell called the nucleoid. And most prokaryotes have a cell wall outside the plasma membrane.
Answer: Xiao can use these structures to create a similarity matrix that enables to differentiate between synapomorphies and homoplasies .
Explanation: A synapomorphy is a trait that has been inherited from the same ancestor, this trait enables to establish a relation of homology between two or more species; while a homoplasy is an analog structure that doesn't have homology.
The bird species has presumably adapted to the conditions after the forest fire if they're still alive. They might have found a new shelter to live at and foods to eat and make it durable for the time period remaining to keep surviving.