Ap Biology Chapter 4 Study Guide

Transcription is the formation of an RNA strand from a DNA template within the nucleus of a cell. There are four nucleotides of DNA. These are adenine, cytosine, guanine and thymine. These nucleotides are transcribed to form messenger ribonucleic acid (mRNA) consisting of nucleotides made of adenine, cytosine, guanine and uracil. This transcription from DNA to mRNA happens by an RNA polymerase II. This newly created mRNA is read in the 5' to 3' direction in sets of 3. These sets are called codons. Each mRNA also has a cap and end. On the 5 prime side is a methylated guanine triphosphate and on the 3 prime is a poly A tail. Messenger RNA then moves to the cells cytoplasm and through the cells ribosomes for translation. Messenger RNA is matched to molecules of transfer RNA (tRNA) in the ribosomes to create amino acids. These amino acids subsequently form an amino acid chain. (Osuri, 2003) A visual representation of this can been viewed in figure 3.

Concept 6.1 Biologists use microscopes and the tools of biochemistry to study cells 1. The study of cells has been limited by their small size, and so they were not seen and described until 1665, when Robert Hooke first looked at dead cells from an oak tree. His contemporary, Anton van Leeuwenhoek, crafted lenses and with the improvements in optical aids, a new world was opened. Magnification and resolving power limit what can be seen. Explain the difference. Magnification is the ratio of an object’s image size to its real size. Resolution is a measure of the clarity of the image; it is the minimum distance two points can be separated and still be distinguished

O'Leary, J. (2010). How is EM different from light microscopy? Retrieved April 25, 2015, from http://bsp.med.harvard.edu/node/222

Translation is the process in which ribosomes synthesize proteins using the mRNA transcript produced during transcription. AT first, the mRNA binds with a ribosome so that it can be decoded one codon at a time. Each codon codes for an amino acid is activated. A tRNA molecule has two ends: one that has a specific binding site for a particular sequence of nucleotides, an anticodon that can base pair with a codon. Appropriate tRNA molecules attach to, then carry the activated amino acid to the ribosome. Anticodons air with codons to bring the specific amino acid to the correct place. A second tRNA repeats this process and the first tRNA releases its amino to the second tRNA. The two amino acids form a peptide bond using the energy from ATP. The ribosome reads the next codon and then another tRNA comes along to repeat the process. As tRNA come and go, amino acids link together, forming more peptide bonds. Eventually, a polypeptide chain in synthesized and it undergoes its conformational changes to carry out its function as a protein. DNA Replication and protein synthesis are both similar and

The mRNA will first go to the cytoplasm and attach with ribosome. The ribosome will help mRNA to produce the chain of amino acids, which will produce the final product- luciferase enzyme. To produce

The first part of this process is called transcription, where the DNA of a gene is turned into mRNA. The second part of this process, translation, is where the mRNA is turned into a protein. The transcription process is regulated by small proteins called transcription factors. The location of the transcription factors' binding to DNA, determines which genes the cell expresses. Different transcription factors are operating actively in different cell types, which causes different cell types to produce different proteins, which causes each cell to have a unique distinctive

5. The MRNA strand detaches from the DNA and moves out of the nucleus into the cytoplasm. 6. The mRNA passes through a ribosome when it passes through each bases causes an amino acid to be attached to a particular protein that is made in the Ribosome. Which is then translated to a correct sequence of amino acids at a ribosome.

Translation is when the mRNA is read by the ribosome to create protein, linking together each specified amino acid. An mRNA attaches to the ribosome. Transfer RNA (tRNA) is small RNA molecules that carry the amino acids to the ribosome for their polymerization into a polypeptide. An mRNA and a tRNA carry the first amino acid and which binds to the start codon. Then, the amino acids are brought to the mRNA by tRNA’s and are added, one by one, to a growing polypeptide chain. Finally, a stop codon in the mRNA is recognized by a protein release factor, and it comes apart releasing a completed

After the process of transcription has happened then the process of translation comes in. Translation is the process that puts the amino acids in a specific order. When mRNA comes back out of the nucleus

All cells function through the proteins. Protein synthesis involves two steps: transcription and translation. During the transcription phase the information encoded in DNA is taken and encodes it to messenger RNA (mRNA) which is smaller than DNA so it can come out of the cells nucleus into the cytoplasm. In transcription the DNA is transcribed to mRNA which is one strand of the double stranded DNA. In the translation phase the mRNA works with a ribosome and transfer RNA (tRNA) to synthesise proteins and occurs in the cytoplasm. The tRNA translates the nucleotide sequence of mRNA to the specific amino acid sequence. These amino acid sequences join together to form a

When the mRNA arrives at the ribosome, the mRNA will connect to the end of it. From here the information on the mRNA will be read. On the mRNA are codons, a set of three nitrogenous bases in DNA or mRNA, these codons are what is being read. When the placement of codons has been looked over, the transfer RNA (tRNA) is activated and begins to match each codon with an anticodon that is in the tRNA. Together the codon and the anticodon create amino acids that are joined by peptide bonds, these amino acids are the building blocks of

Ribosomes- This is a tiny particle made up from RNA and a large number of proteins found in the cytoplasm. Ribosomes bind to messenger RNA and then synthesises proteins.

Polypeptides are chains of amino acids, which are all proteins. Proteins are made and developed outside the nucleus; in the ribosome. The way strung amino acids are put together is very important. The individual 3D and sequence must be correct, or else you will have a completely different protein. There are two different types of RNA which are involved in the entire process. They are transfer RNA (tRNA) and messenger RNA (mRNA). The mRNA, in the process of making new proteins, makes a copy of a gene which exits the nucleus. It sends the information which is needed to make new polypeptides. You might think that it goes straight to connecting to the ribosome, but it does not. First the copy of the gene goes to the Endoplasmic Reticulum (ER).

The RNA copy (messenger RNA) of the protein genetic information encoded in DNA molecule is produced in the nucleus. Each mRNA encodes the information for a single protein. They are single strands of nucleotides created during the process of transcription, which acts as a messenger that carries codes from the DNA in the nucleus to the cytoplasm. The mRNA molecules exit the nucleus through tiny openings called nuclear pores. In the cytoplasm, the protein polymers are synthesised through chemical reactions and this helps to enable the actual protein synthesis. Once it exits the nucleus and enters the cytoplasm, the mRNA can interact with the ribosome, which is the cell’s assembler within the process of protein synthesis. The ribosome is made up

Scanning Electron Microscope-(SEM) it is a type of electron microscope that also uses a magnetic fields within a vacuum tube to manipulate a beam of electrons. The surface of the specimen need to be coated with a metal such as platinum or gold. It is used to observe the surface details of microbes and cellular structures, and this can be a disadvantage since it does not magnify the internal structures of the specimen. It can magnify up to 10,000x with a resolution about 20nm. The resulting image is in 3D and can be enhance with color.