BIO 111 FINAL EXAM (Chapters 11-12 are first)

Epigenetic control

"in addition to genetics". It is the study of how cells and organisms change gene expression and function without changing the base sequence of their DNA. Epigenetic control works in three ways: 1. Modification of DNA 2. Modification of chromosomal proteins 3. Changing transcription and translation through the actions of several types of RNA collectively called noncoding, or regulatory, RNA. - important because transcription and translation must be controlled so that the appropriate amounts of specific proteins are present in the specific cell types under specific conditions. Noncoding RNAs can reduce or enhance transcription, depending on the exact nature of the epigenetic controls that are affected.

Chemical structure of DNA: 1. listing the four nitrogen containing bases, sugars, and phosphate group for DNA nucleotides. 2. Diagramming how the nucleotides are arranged within the DNA double helix. 3. Relating the formation of a base sequence to the genetic message.

1. Adenine, guanine, thymine, and cytosine 2. Adenine and guanine (purine bases) have a double ring structure, while thymine and cytosine (pyrimidine bases) have only a single ring. 3. The bases point inward toward each other from the sugar-phosphate backbone like rings on a ladder.

Electron energy levels

1st- 2 2nd- 8 3rd- 18

Disaccharides

2 sugars joined together- maltose and sucrose

Equation for photosynthesis

6CO2 + 6H2O + Light energy ARROW C6H12O6 + 6CO2

Solvent

A fluid capable of dissolving a solute

Glycolysis

A molecule is split into 2 pyruvate molecules (a 3 carbon molecule) and 2 ATP molecules are formed

Ribosome

A particle consisting of RNA that serves as a workbench for the synthesis of proteins within the cell cytoplasm

Predict if someone has inherited cystic fibrosis based on diagnostic array analysis

A person's DNA is tested for cystic fibrosis by cuttinig into small pieces, separating the pieces into single strands, and labeling the strands with a colored molecule. The array is then bathed in the resulting solution of labeled DNA fragments. Under the right conditions, only perfect complimentary strand of the person's DNA will bind to any given probe on the array, thereby showing which CFTR alleles (cystic fibrosis is caused by a defect in protein, called CFTR) the parent possess.

Solute

A substance that can be dissolved by a solvent.

Light reactions

ATP and NADPH capture light energy. Water us split and oxygen gas is released as a by product

Autotroph

Ability to make own food. Producers- plants

Autosome

Any chromosome not considered a sex chromosome, not involved in sex determination.

Biotechnology

Any use or alteration of organisms, cells, or molecules to produce food, drugs, or other goods.

Glyolysis equation

C6- splits into 2 molecules of C3

Glucose (monosaccharide)

C6H12O6

Equation for cellular respiration

C6H12O6 + 6CO2 ARROW 6CO2 + 6H2O + ATP

Aerobic respiration equation

C6H12O6 + 6CO2 ARROW 6H2O + energy

4 common elements

Carbon, hydrogen, nitrogen, and oxygen

Pinocytosis

Cell drinking

Phagocytosis

Cell eating

Cleavage furrow

Cell wall of an animal????

Difference between cellular respiration and photosynthesis

Cellular respiration breaks down sugars to make ATP (end product), while photosynthesis creates sugars (end product). The processes overall chemical equations are the reverse of each other.

Explain the molecular basis of a gene mutation.

Changes in the sequence of DNA nucleotide bases result in altered genes. Arise from DNA replication errors, certain chemicals and environmental factors.

Denatured

Changing shape of an enzyme changes its function and it does not work.

Codon and anticodon

Codon- found in DNA and mRNA. Codon is complimentary to a triplet of template strand. It determines the position of an amino acid in a polypeptide. *** specifies which amino acids will be incorporated into a protein*** Anticodon- Occurs in tRNA. It is complimentary to a codon. It helps in bringing a particular amino acid at its proper position during translation. ** group of three bases, which portrudes from each tRNA. Complimentary base pairing between codons mRNA and anticodons of tRNA specifies which amino acids are used during protein synthesis***

Complementary base pairing

Complimentary base pairs are bases that bond with each other. Adenine bonds only with thymine and guanine bonds only with cytosine.

Cytoplasm

Consists of all the fluid and structures that lie inside the plasma membrane but outside the nucleus.

Organic molecules

Contains carbon- carbs, lipids, proteins, nucleic acids

3 ways DNA can recombine in nature

DNA recombination occurs naturally through processes such as sexual reproduction, bacterial transformation (gene transfer between different bacteria as they pick up either free DNA from the environment or tiny circular DNA plasmids), and viral infections, which may transfer DNA between bacteria or between eukaryotic species.

Recombinant DNA

DNA that is altered by the incorporation of genes from other organisms, often from different species.**Recombinant DNA is transferred into animals or plants using vectors or carriers such as bacteria or viruses to make transgenic organisms expressing DNA that has been modified or derived from another species.

Calvin Cycle

Dark reactions,

DNA

Deoxyribonucleic acid- contains the genetic information of all living cells.

R group

Determines type of amino acid/name

Relationship between genes, chromosomes, and DNA

Each strand of DNA is a chromosome. A gene is a small segment of DNA DNA contains hereditary materials

Kinetic energy

Enegy of movement

2nd law of thermodynamics

Energy can be transferred into different kinds of energy. However when this happens, the amount of useful energy decreases, like when the potential energy in a car transforms to heat being released, the heat released is unusable energy.

1st law of thermodynamics

Energy cannot be created nor destroyed

Animal cloning

Example using Finn Dorset ew and Blackface ewe 1. Cells from the udder of Finn are grown in culture with low nutrient levels. The starved cells stop dividing. 2. The nucleus is sucked out of an unfertilized Blackface. This egg with provide cytoplasm but no chromosomes 3. The egg cell without a nucleus and the non dividing udder cell are placed side by side in a culture dish. An electric pulse stimulates the cells to fuse and initiates mitotic cell division. 4. The cell divides, forming an embryo that consists of a ball of cells. 5. The ball of cells is implanted into the uterus of another blackface. 6. The blackface gives birth to a female Finn, a genetic twin of the Finn.

Peptide bonds

Find them between amino acids. Only found in proteins

Ionic bonds

Gain or loss of electrons

Cause of most cancers

Gene mutations after birth (not inherited)

Amount of ATP produced

Glycolysis and Krebs cycle= 2 ATP Electron transport chain= in the 30s of ATP

Eukaryotic

Has nucleus- humans, complex

Base

Higher than 7 (7-14). Higher the more of a base it is. Has more OH. Also called alkaline

Microtubules

In charge of movement of chromosomes during mitosis.

Polygenic inheritance

Interactions between two or more genes that result in things like height. This means that phenotypes vary and are hard to define because they are strongly effected by the environment. Research sats there is 180 genes contributed to height

Endocytosis

Into the cell

Nucleus

Large organelle with three parts: 1. Nuclear envelope- Nucleus is isolate from the rest of the cell by a double bond 2. Chromatin- Contains a bunch of chromosomes (DNA double helix that helps to organize and regulate the use of DNA. 3. Nucleolus- "little nuclei". Site of ribosome nucleus

Chlorophyll in photosynthesis

Light strikes it then the electrons enter an excited state of higher energy then sugar is formed.

Cellular respiration

Makes ATP when oxygen is present, known as aerobic because it needs oxygen to take place. Takes place in mitochondria

List the three major types of RNA and identify the function of each.

Messenger RNA (mRNA)- carries DNA gene information to the cytoplasm to be used in protein synthesis. Transfer RNA (tRNA)- brings amino acids to the ribosome, where they will be put into a proteins. Ribosomal RNA (rRNA)- a part of the structure of ribosomes.

Genetic engineering

Modification of DNA. Used for specific goals: 1. understand more about cellular processes, including inheritance and gene expression. 2. better understand and treat various genetic disorders. 3. Generate economic and social benefits, including better agricultural organisms and valuable biotechnological molecules.

Inorganic molecules

No carbon-water

Prokaryotic

No nucleus, simple and small

Asexual reproduction

Offspring are formed from a single parent, without having sperm fertilize an egg. Produces offspring that are genetically identical to the parent and each other- they are clones

Cell wall

Only found in plants, bacteria, and fungi, NOT ANIMALS. It protects and supports the cell- nonliving, relatively stiff coatings that are secured outside the plasma membrane.

Exocytosis

Out of the cell

Diffusion

Over time, random movements of solutes produce a net movement from regions of higher concentration to regions of lower concentration.

Chloroplasts

Performs photosynthesis

Plasma membrane

Phospholipid bilayer with scattered proteins, allows things in and out of the cell, isolates or separates cell continents from the external environment, and allows communication with other cells and with extracellular environment.

Chlorophyll

Pigment found in chloroplasts that capture light energy during photosynthesis. Gives plant green color, found inside chloroplasts.

Transgenic or genetically modified organisms (GMCs)

Plants and animals that contain DNA that has been modified or derived from other species.

Photosynthesis

Process by which light energy is captured and stored as chemical energy.

Mitochondrion

Produces energy- power house of the cell that extracts energy from food.

Enzymes

Proteins, break things down in the body. Substrate joins together at the active site creating the enzyme.

RNA

Ribonucleic acid- involved in converting the information in DNA into protein. Also the genetic material in some viruses. All cells contain DNA and RNA.

Characteristics of stem cells and hypothesis how they can be used to treat the genetic disorder SCID (severe combined immune deficiency)

SCID is a rare disorder in which a child fails to develop an immune system. Infections that would be trivial in a normal child become life threatening. In some cases, if the child has an unaffected relative with a similar genetic makeup, a bone marrow transplant from the healthy relative can give the child functioning stem cells, so that he or she can develop a working immune system.

Meiosis

Sex cells- sperm and egg. Goes through cell division twice.

Covalent bonds

Sharing pairs of electrons

Endoplasmic reticulum: smooth and rough

Smooth- synthesis of lipids Rough- synthesis of proteins

Mitosis

Somatic cells (body cells, not sex).

Differentiated cells

Specialized

Potential energy

Stored energy

Metabolism

Sum of all chemical reactions

Genotype

Symbols, Ex- Pp or PP

Osmosis

The diffusion of water.

Plasmids

Tiny circular DNA molecules. Plasmids may contain genes for metabolism of new energy sources (petroleum, for example), for diseases in organisms the bacteria infect (like diarrhea), for antibiotic resistance (such as resistance of penicillin).

Introns, exons, and RNA splicing

To convert the prE-mRNA molecule into the finished mRNA, enzymes in the nucleus cut the pre-mRNA apart Introns- noncoding segments, called at the junctions between introns and extrons, splice together the protein- coding exons, and discard the introns. introns because they are INtragenic, meaning with "within a gene". Exons- coding segments, called exons because they are EXpressed in protein. RNA splicing- In molecular biology, splicing is the editing of the nascent precursor messenger RNA (pre-mRNA) transcript. After splicing, introns are removed and exons are joined together (ligated). For nuclear-encoded genes, splicing takes place within the nucleus either co-transcriptionally or immediately after transcription.

Krebs cycle

Transfer energy to electron transport chain

Heterotroph

Unable to make own food. Consumers.

Genes

Units of inheritance Encode information needed to produce proteins, cells, and entire organisms. Parts of chromosomes, their location on a chromosomes is called the locus.

Stem cells

Unspecialized

Phenotype

Words, one quarter blue etc

Effects a mutation can have on: a. protein structure and function b. evolution

a. Consequences for an organism's structure and function depend on how the mutation affects the protein encoded by the mutation gene. The effects of mutations depend on how they alter the codons on mRNA. 1. Inversions - mutations that occur when a piece of DNA is cut out of a chromosome, flipped around, and reinserted in a reveresed oritentation. Translocations- mutations that occur when a piece of DNA is removed from one chromosome and attached to another. -these types of mutations occur when pieces of DNA are broken apart and reattached. These mutations can benign or very serious. Half of cases of severe hemophilia are due to inversion in the gene that encodes a protein required for blood clotting. 2. Deletions- One or more pairs of nucleotides are removed from the gene. Insertions- One or more pairs of nucleotides are inserted into a gene. - the effects of deletions and insertions usually depend on how many nucleotides are removed or added. Tho the protein may be changed, it usually is minor, and still makes sense. 3. Substitutions- also called point mutation, is when a single base pair in DNA is changed. This type of mutation may cause four different effects: the amino acid sequence of a protein may be unchanged, the protein function may be unchanged, protein function may be changed by an altered amino acid sequence, and protein function may be destroyed by a premature stop codon. b. Mutations provide the raw material for evolution- new base sequences undergo natural selection as organisms compete to survive.

How Biotechnology is used to make GMOs

a. DNA Cloning- Once a gene is obtained, it can be used to make transgenic organisms. Therefore, it is essential to have a huge number of copies of the gene. The simplest way to generate lots of copies of the gene is to let living organisms do it, by DNA cloning. In DNA clothing, the gene is usually inserted into single-celled organisms, such as bacteria or yeasts, that multiply very rapidly, manufacturing copies of the gene as they do. The most common method of DNA cloning is to insert the gene into a bacterial plasmid, which will be replicated when bacteria containing the plasmid multiply. Inserting the gene into a plasmid, rather than a the bacterial chromosome, also allows it to be easily separated from the majority of the bacterial DNA. b. Restriction enzymes- cuts DNA at a specific nucleotide sequence. There are hundreds of different restriction enzymes. Many cut straight across the double helix of DNA. Others make a staggered cut, snipping the DNA in a different location on each of the two strands, so that single-stranded sections hang off the ends of DNA.These single-stranded regions are commonly called "sticky ends", because they can base-pair with, and thus stick to, other single-stranded pieces of DNA with complimentary bases. Restriction enzymes that make a staggered cut are used in DNA cloning. c. DNA ligase- specific type of enzyme, that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond. d. Transfecting- to introduce foreign DNA into a host cell; usually includes mechanisms to regulate the expression of DNA in the host cell. In the ideal case, the bacteria or viruses insert the new gene into the chromosomes of the host organism's cell, where it becomes a permanent part of the host;s genome, and is replicated whenever the host's DNA is replicated. This is how some plants were transfected with genes for herbicide resistance and insect resistance. A simpler method is to use a "gene gun". Microscopically small pellets of gold are coated with DNA (either plasmids or purified genes) and then shot at cells or organisms. This process is "hit or miss", but it is often quite effective for plants, cells in culture, and sometimes even whole animals. Gene guns are often used when host organisms are easily available in large numbers, so that low success rate does not matter much. Finally, plasmids or purified genes can be directly injected into animal cells, usually fertilized eggs. Tiny glass pipettes are loaded with a suitable solution containing DNA. The pipettes have tips that are sharp enough to impale a cell without damaging it. Pressure applied to the back of the pipette pushes some of the DNA into the cell.

Gene regulation

a. Gene regulation in prokaryotes- prokaryotic DNA is organized into packages called operons which contain various components: Regulatory gene- controls the timing or rate of transcription of other genes Promoter- which RNA polymerase recognizes as the place to start transcrbing Operator- governs the access of RNA polymerase to the promoter or to the structural genes Structural genes- actually encode the related enzymes or other proteins. -The lactose operon is an example of gene regulation in prokaryotes. Lactose operon contains three structural genes, each coding for an enzyme that aids in lactose metabolism. The lactose operon is shut off, or repressed, unless activated by the presence of lactose. The regulatory gene of the lactose operon directs the synthesis of a REPRESSOR PROTEIN that binds to the operator site. b. Gene regulation in Eukaryotes- regulation of gene expression in eukaryotic cells can be controlled at any of a number of steps: 1. Cells can control the frequency at which an individual gene is transcribed. 2. The same gene may be used to produce different mRNAs and protein products. 3. Cells can control the stability and translation of mRNAs. 4. Proteins may require modification before they carry out their function. 5. Cells can control the rate at which proteins are degraded. c. Eukaryotic cells may regulate the transcription of individual genes, regions of chromosomes, or entire chromosomes: 1. regulatory chromosomes that bind to a gene's promoter alter its rate of transcription- many transcription factors require activation before they can affect gene transcription. 2. Some regions of chromosomes are condensed and not normally transcribed. 3. Large parts of chromosomes may be inactivated, preventing transcription.

Advantages an disadvantages of biotechnology being used to produce:

a. Herbicide resistant transgenic crops- allow farmers to kill weeds without harming their crops. Less competition from weeds means more water, nutrients, and light for the crops, meaning larger harvests. Many herbicides kill plants by inhibiting an enzyme that is used by plants, fungi, and some bacteria- but not animals- to synthesize specific amino acids. Without these amino acids, the plants die because they cannot synthesize proteins. b. Insect resistant (Bt) transgenic groups- the insect resistance of many groups has been enhanced by giving them a gene, called Bt, from the bacterium Bacillus thuringiensis. The protein encoded by the Bt gene damages the digestive tract of insects, but not mammals. Transgenic Bt crops often suffer far less damage from insects than do regular crops, so farmers can apply less pesticide to their fields. c. Edible vaccines- The tools of biotechnology can also be used to insert medically useful genes into plants, producing medicines down on the "pharm". For example, a plant may be engineered to produce harmless proteins that are normally found in disease-causing bacteria or viruses. If these proteins resist digestion in the stomach and intestine, simply eating such plants could act as a vaccination against the disease-causing organisms. This would mean there is no need for purified vaccines or needles etc. However, modern day biomedical researchers have said this is not a good idea because we cannot control the doses, too little and the user does not develop decent immunity and too much might cause the vaccine proteins to be harmful. d. transgenic animals that produce human proteins used in medical treatments- different things are injected into animals so that when we eat them we get the benefits from the things injected. Healthier things can be injected into pigs, for example, so that when we consume ham we take in these healthy things. Also, diseases like Alzheimer's is injected in mice so we can work on cures. e. Golden rice- Vitamin A is injected so that places that have a shortage of vitamin A can consume the vitamins needed. It is the perfect crop for people in Asians countries because rice is the majority of the energy these people consume, so it is easy to get vitamin A in this way.

Explain process of DNA replication

a. Its semi conservative nature: Each time it replicates, it keeps one old strand and makes one new. b. The role of DNA helicase: Pulls apart the parental DNA double helix, so the bases of the two DNA strands no longer form base pairs with one another. c. The role of DNA polymerase and free nucleotides: Polymerase move along each separated parental DNA strand, matching bases on the strand with complementary free nucleotides (previously synthesize in the cytoplasm and imported into the nucleus). d. The role of DNA primase: Creates a short RNA sequence so DNA can copy itself. e. The role of DNA ligase: Enzyme that ties DNA together

Identify the chemical structure of RNA by

a. Listing the four nitrogen-containing bases, sugar and phosphate group for RNA nucleotides: Uracil (takes place of thymine) Cytosine, Adenine, Guanine b. Diagramming how the nucleotides are arranged within an RNA molecule: Ribose has two OH's rather than Deoxyribose's 3 H's and one OH. *** A-U G-C and vice versa********

Define and give examples of the following mutations that may occur in chromosomes

a. Point mutation: Substituting one nucleotide for another. (ex: change T to A) b. Insertion mutation: One or more new nucleotide pairs inserted into the DNA. c. Deletion mutation: 1 or more nucleotide pairs are removed from DNA

How DNA is used in criminal investigations

a. Polymerase chain reactions- Amplifies DNA and can be used to make billions or trillions of copies of selected DNA. Two major steps: 1. marking the DNA segment to be copied 2. running repetitive reactions to make multiple copies. It is then ready for forensics, cloning, making transgenic organisms, etc. Used to amplify DNA so there is enough to compare to the DNA left at a crime scene with a suspects DNA. b. Short tandem repeats- specific segments of DNA, they can be used to identify people with astonishing accuracy. STRs are short (about 20-250 nucleotides), repeating (consisting of the same sequence of 2 to 5 nucleotides repeated up to 50 times), and tandem (having all of the repetitions right alongside one another). c. Gel electrophoresis- Where a mixture of DNA pieces can be separated. DNA mixed into a gel where they are put into a chamber with electrodes connected to each end. There is one positive and one negative electrode, current will flow between the electrodes through the gel. The phosphate groups in the backbones of DNA are negatively charged. When electrical current flows through the gel, negatively charged DNA fragments move toward the positively charged electrode. Because smaller fragments slip through the holes in the gel more easily than larger fragments, they move more rapidly toward the positively charged electrode. Eventually, the DNA fragments are separated by size, forming distinct bands on the gel. d. DNA probes- Pieces of synthetic DNA, can base-pair with specific DNA fragments in the sample. They are short pieces of single stranded DNA that are complimentary to the nucleotide sequence of a given STR or any other DNA of interest in the gel). Used to label specific nucleotide sequences. The DNA probes are labeled either by radioactivity or by attaching colored molecules to them. Therefore, a given DNA probe will label certain DNA sequences, but not others. e. DNA profile- A pattern from the gels of DNA samples in STR. Unrelated people almost never have identical DNA profiles. The position on the bands of the four nucleotide sequence of each STR allele. If the same STRs are analyzed, then all the samples of a person's DNA produce the same profile every time.

Diseases and shit

a. Sickle-cell anemia: caused by recessive allele. Caused by a defective allele for hemoglobin synthesis. It is an inherited form of anemia that results from a mutation in the hemoglobin gene. Low blood cell count or below-normal hemoglobin in the blood. b. Albinism: Caused by recessive alleles. Defect in melanin production. Results in very pale hair and skin. Comes from a homogeneous defective tyrosinase allele. Normal people have one or two functional tyrosinase alleles. c. Color blindness: Sex linked inheritance. Red green color deficiency. d. Hemophilia: Sex linked. Caused by a recessive allele on the X chromosome that results in a deficiency in one of the proteins needed for blood clotting. People with this will bruise easily and may bleed excessively from minor injuries. Some males survive long enough to pass on their defective allele to their daughters who in turn pass it on to their sons. e. Huntington's disease: Caused by dominant alleles. Caused by a defective protein that kills cells in specific brain regions. Dominant disorder that causes a slow; progressive deterioration of parts of the brain., resulting in loss of coordination, flailing movements, personality disturbances, and eventual death. People normally do not get symptoms until they are between 30 and 50. f. Carrier: A carrier for a genetic disorder is a person who is heterozygous, with one normal, dominant allele and one defective, recessive allele; That person is phenotypically healthy but can pass on his or her defective allele to offspring causing problems. g. Karyotype: A picture of a person's chromosomes. Used to determine the size, shape, and number of chromosomes. Grouped together in pairs, arranged in order of decreasing size. h. Test cross required when: Used to determine if a group exhibiting a dominant trait is homozygous or heterozygous for that trait. Basically, they determine the genotype of an individual with a dominant phenotype. I. Turner syndrome: Abnormal number of chromosomes. Having only one X chromosome. Also called monosomy X, meaning having one X chromosome. This makes girls have trouble menstruating or developing secondary sexual characteristics like enlarged boobs. Also, they lack mature eggs so they cant produce offspring. Characteristics also include short stature, folds of skin around the neck, and increased risk of cardiovascular disease, kidney defects, and hearing loss. Also have higher chances of color deficiency and hemophillia. J. Trisomy X: Having three X chromosomes. Also called triple X. Only difference between XXX and XX is a tendency to be taller and to have a higher incidence of learning disabilities. Also, they are fertile and seem to always bear healthy normal chromosomed children. K: Kinefelter syndrome: Male being born with an extra X chromosome (XXY). A lot of these men go through life never noticing the issues, however, some at puberty get partial breasts, broadening of the hips, or small balls. Some of these men can be infertile because of low sperm count. L: Jacob syndrome: Males with extra Y (XYY). Norammly no effect is seen, but sometimes they are taller than average. Also may have slightly above average chance of learning disability. M: Downsyndrome: unlike the others this is caused by abnormal number of autosomes. Also called Trisomy 21. It is an extra copy of chromosome 21. Physical features: weak muscle tone, a small mouth normally held partially open because it cannot contain the tongue, and distinctively shaped eye lids. Also have heart malfunctions, low resistance to infectious disease, and varying degrees of mental retardation. This can happen by the age of the mother (older= worse chances) can also happen by nondisjunction in sperm.

Explain the process of protein synthesis in detail

a. Transcription involving a DNA template, promoter, RNA polymerase, and m-RNA: DNA that encodes for a gene is copied onto mRNA in the nucleus. There are 3 stages: 1. Initiation- where transcription begins, and where RNA polymerase binds to the promoter of a gene. RNA polymerase binds at the promoter region (TATAAA sequence), and DNA begins to unwind. 2. Elongation- generates a growing strand of RNA. RNA polymerase synthesizes RNA that is complimentary to template strand of DNA. 3. Termination- where transcription stops, RNA polymerase continues down the template strand of DNA until it reaches a sequence of bases called the termination signal. RNA polymerase then releases the composed RNA and detaches from the DNA. b. Translation involving mRNA, tRNA, the ribosome, and amino acids and protein: During translation, mRNA, tRNA, and Ribosomes cooperate to synthesize proteins. Translation is similar to transcription, they each have three steps. 1. Initiation- translation begins when tRNA and mRNA bind to a ribosome. The preinitiation complex scans the mRNA for an initiation codon, AUG, which codes for methionine. The initiation complex forms. The large ribosomal sub unit joins the complex. 2. Elongation- amino acids are added one at a time to the growing protein chain. The ribosome holds two mRNA codons in both binding sites. Peptide bond forms between two amino acids. The complex moves one codon along mRNA. This process repeats one codon at a time. 3. Termination- a stop codon signals the end of translation. Translation stops when the stop codon is reached. Special proteins bind to the ribosome. Ribosome releases the complete protein. Ribosome and mRNA dissociate.

Major ethical issues of modern biotechnology:

a. safety concerns with genetically modified foods- It has been shown that GMOs in food haven't shown to be unhealthy or dangerous to humans. For example, a company has produced transgenic salmon containing extra genes for growth hormone. The fish grow faster, but will have the same proteins in their flesh as any other salmon. However, some people may be allergic to genetically modified plants. Like when nuts were inserted into soy beans to bring up the protein, but it was found many who were allergic to peanuts would be allergic to soy beans as well, this product never got to the market. b. effects of genetically modified foods in the environment- A clear positive is that farmers apply less pesticide to their fields, which translates to less pollution and less plants suffering pesticide poisoning. However, herbicide- resistance genes may spread outside the farm. Because the genes of this are incorporated into the genome of the transgenic crop, the genes will be in its pollen too. A farmer cannot control where where pollen will travel. But, most plants and animals that come into contact with this will not really be harmed. However, fish have the potential to pose more significant threats because they can disperse rapidly and are nearly impossible to recapture. Other animals are not a big threat because they do not move much in areas that may be affected so it will not spread, because fish move so much around it can be spread all over and for generations over. c. Human genome changes- finding out if a child in the womb has, for example, downsydrome and then deciding whether or not to have an abortion has become one issue. Another is a question of whether or not people should be allowed to select, or change the genomes of their offspring. An example of this was when girl was born with a disease where she needed a bone marrow transplant with a compatible donor. Her parents had a doctor take sperm and egg cells from them to create dozens of embryos to create another child and who could provide a compatible bone marrow transplant. The embryos were tested and then once one was good, they put it in the mother, and nine months later they had a boy and used the blood from the umbilical cord to provide stem cells for the bone marrow transplant.

Polyaccharides

complex sugar/many sugars-glycogen and cellulose

Telomeres

end body, protective caps at end of chromosomes that help genes stay on.

Characteristics of living things

growth, metabolism, evolution, reproduction, and response to stimuli

Nucleotides

long chains of sub units in DNA.

Acid

lower than 7 (0-6.9). Lower means higher acidic level and has more hydrogen

Atomic number

number of protons

Atomic mass

protons plus neutrons