MicroBio Chapter 8

Summarize the steps of bacterial DNA replication, and identify the enzymes used in this process

*Table 8.1 of enzymes used -Helicase - unzipping the DNA helix -Primase- synthinicing an RNA primer -DNA polymerase 111- adding additional strands, making a new strand, each daughter strand would have a new and old strand. Doing most of the replication. -DNA polymerase 1- -Ligase -Topoisomerases

Define the terms genome and gene and genetics

- Genome the sum total of genetic material of an organism. Mostly in the form of chromosomes, but occasional in bacteria and viruses its extra pieces of DNA called, plasmids. -Most of the genome exists in the from f chromosomes -Some appear as plasmids or in certain organelles of eukaryotes -Genome of cells composed entirely of DNA -Genome of viruses can contain either DNA or RNA NOT BOTH. - Gene has a certain segment of DNA that contains the necessary code to make a protein or RNA molecules -Genetics the study of inheritance or heredity of living things: -The transmission of biological properties from parent to offspring -The expression and variation of those traits -The structure and function of the genetic material -How genetic material changes

Catabolic operons

-Induced by the substrate of the enzyme for which the structural genes code -Only produce the enzyme when the substrate is present.

Nucleotide: Basic unit of DNA structure

-Phosphate Deoxyribose sugar -nitrogenous base

Differentiate between genotype and phenotype

-Structural genes: - Code for proteins, -Genes that code for RNA machinery used in protein production, Regulatory genes that control gene expression - Genotype: An organisms distinctive genetic make up. -The sum of all gene types an organisms distinctive genetic makeup. -Phenotype: How that genetic make up is expressed and phenotype can change depending on which genes are turned on. -The expression of certain traits (strutters or functions).

Repressible operons

-anabolic enzymes -turned off by the product synthesized by the enzyme

The Lactose operon: three features of the lac operon

-regulator: composed of the gene that codes for the protein capable of repressing the operon (repressor). The repressor can cut off the production of enzymes when they aren't needed. -control at the location/locus same: Promoter: recognized by RNA Operator: Turns off/on -structural locus/location made uo of three genes coding for a different enzyme

8.6 Explain the importance of restriction endonucleases to genetic engineering

Being able to take the tools of nature and applying them to science. restriction endonucleases: Enzymes capable of recognizing foreign DNA and breaking the bonds between adjacent nucleotides on both strands of DNA. protects bacteria against incompatible DNA of bacteriophages Scientists can use to cleave DNA at desired sites (recombinant DNA engineering) -Recognize and clip at PALINdrOMES.

8.1 Chromosomes:

Chromosome: Discrete...PP Eukaryotic chromosomes - DNA wound around histones -Located in the nucleus -Diploid in paris and Haploid single -Linear appearance Bacterial chromosomes: - Single circular chromosome -DNA condensed into a packet by means of histone-like proteins

Conjugation: Exchanging genes:

Conjugation: genetic material is transferred from a donor cell to a recipient cell via a direct connection. The donor gives the recipient a strand and then the recipient duplicates the strand itself. Gram-negative conjugation: Gram positive conjugation

Gentic regulation of protein synthesis

Control mechanisms ensure that genes are active only when they are required. -Enzymes produced as needed.

Highlight the main points of lac operon operation

Lac operon: multiple genes all in a row It goes in order of lac Z-->Y-->A

Liagase

Ligase: necessary to seal the sticky ends together used in the final slicing of genes into plasmids and chromosomes

When would you turn a lac operon on?

On she glucose levels are low and lactose levels are high

Define the term operon and explain one advantage it provides to a bacterial cell

Operon: Only found in bacteria Consist of a coordinated set of genes regulated as a single unit. Inducible or repressible

list the steps in the polymerase chain reaction

Polymerase Chain reaction: Amplification: rapidly increases the amount of DNA in a sample without the need for making cultures or carrying out complex purification techniques. Rapid enough to replicate target DNA from a few copies to BILLIONS of copies in a few hours. Primers: DNA strands 15-30 bases long that serves as land markers where DNA amplification should begin. DNA Polymerase from a hot spring source: "taq" polymerase isolated from thermus aquaticus Thermal Cycler: Automatically performs the cyclic temperature changes required for PCR.

Explain the characteristics of a recombinant organism.

Recombinant organism: - Recombinant: any organism that contains genes that originated in another organism: Adding additional organisms to it in the lab, intentionally do this. - @PP

Regulation in bacteria, archaea, and eukaryotes:

These both block something in transcription and translated proteins?: -Antisense RNAs -Micro RNAs

Describe three forms of horizontal gene transfer used in bacteria.

Three forms of horizontal gene transfer in bacteria: -Plasmids small circular pieces of DNA replicate independently not necessary for survival can carry seful traits contain their own origin of replication -Chromosomal fragments must integrate into the bacterial chromosome on order to be replicated.