DNA is essentially a storage molecule. It contains all of the instructions a cell needs to sustain itself. These instructions are found within genes, which are sections of DNA made up of specific sequences of nucleotides. In order to be implemented, the instructions contained within genes must be expressed, or copied into a form that can be used by cells to produce the proteins needed to support life.
The instructions stored within DNA are read and processed by a cell in two steps: transcription and translation. Each of these steps is a separate biochemical process involving multiple molecules. During transcription, a portion of the cell's DNA serves as a template for creation of an RNA molecule. (RNA, or ribonucleic acid, is chemically similar to DNA, except for three main differences described later on in this concept page.) In some cases, the newly created RNA molecule is itself a finished product, and it serves an important function within the cell. In other cases, the RNA molecule carries messages from the DNA to other parts of the cell for processing. Most often, this information is used to manufacture proteins. The specific type of RNA that carries the information stored in DNA to other areas of the cell is called messenger RNA, or mRNA.
How does transcription proceed?
Transcription begins when an enzyme called RNA polymerase attaches to the DNA template strand and begins assembling a new chain of nucleotides to produce a complementary RNA strand. There are multiple types of types of RNA. In eukaryotes, there are multiple types of RNA polymerase which make the various types of RNA. In prokaryotes, a single RNA polymerase makes all types of RNA. Generally speaking, polymerases are large enzymes that work together with a number of other specialized cell proteins. These cell proteins, called transcription factors, help determine which DNA sequences should be transcribed and precisely when the transcription process should occur.
Human anatomy deals with the study of the human body, its structures, and how these structures specifically function. Microscopic anatomy on the other hand deals with structures found within the body that cannot be seen by the naked eye but can be viewed with the use of the microscopic. Microscopic anatomy deals with the study of the smallest structures of the cells, tissues, and organs of the body.
Answer:
Carbon dioxide goes with the concentration gradient across the cell membrane. It goes in the direction of the concentration gradient, from high concentration to low concentration.
Explanation:
undergoes simple diffusion, which is an example of passive transport. Passive transport diffusion goes with the concentration gradient, while on the other hand, active transport goes against the concentration gradient.
Going with the concentration gradient means that the molecules move from areas of high concentration to areas of low concentration. This is what carbon dioxide does.
Going against the concentration gradient means that the molecules move from areas of low concentration to areas of high concentration. This goes against the concentration gradient.
Answer:
B. because science only uses facts that are proven 100% true through the use of variable
Answer:
D) Competition between organisms
Explanation:
Random mating between organisms, absence of any factor of evolution (mutation, recombination, gene flow, migration etc.) and a large population size serve to maintain the allele frequency and thereby the phenotype frequency over generations. However, competition between organisms for any natural resource leads to natural selection of "better competing organisms" and increases their phenotype frequency in the population.
