GeneticsJessica Garr, Amanda Melair, Ashley Regan, Jake

Young, Giovanni Marrero

What is Genetics? What are terms associated with Genetics?

Genetics is the study of heredity, or the branch of biology that deals with heredity and genetic variations.

Genotype: What is genetically expressed in an organisPhenotype:What is physically expressed in an organism

Homozygous: Identical pairs of genes for any given characteristic

Heterozygous: Different pairs of genes for any given characteristic

Dominant: The trait that is physically expressedRecessive: The trait that is present but not shown

Mitosis & Meiosis• Mitosis has 4 phases:

• Prophase

• PREPARE

• Chromosomes are visible

• Lose nucleus

• Metaphase

• MIDDLE

• Chromosomes line up in the middle

• Anaphase

• AWAY

• Chromosomes move towards the poles

• Telophase

• TWO NUCLEUS

• Nucleus split and reappears

• They are identical cells

• Body cells

• Diploid cells

• Meiosis goes through 2 processes:

• Prophase l

• Crossing over

• Protiens of chromatids break off and attach to the adjacent chromosomes on the homologous chromosomes

• Metaphase l

• Anaphase l

• Homologous chromosomes seperate

• Telophase l

• Prophase ll

• Mertaphase ll

• Anaphase ll

• Sister chromatids seperate

• Telophase ll

• 4 haploid cells result

• They are similar cells

• Sex cells

• Haploid cells

Stages of Meiosis l and ll

http://thumb7.shutterstock.com/display_pic_with_logo/848740/116607409/stock-vector-vector-diagram-of-the-meiosis-phases-116607409.jpg

STages of Mitosis•http://www.google.com/search?q=mitosis&safe=active&source=lnms&tbm=isch&sa=X&ei=XgubU9GfEJGOyAS2_IKYDA&sqi=2&ved=0CAYQ_AUoAQ&biw=1301&bih=620#facrc=_&imgdii=_&imgrc=nhZ-bmMsNUC3FM%253A%3BUhqCAF-wnFwS9M%3Bhttp%253A%252F%252Fdiffervs.com%252Fwp-content%252Fuploads%252F2013%252F08%252Fmitosis-vs-meiosis.jpeg%3Bhttp%253A%252F%252Fdiffervs.com%252Fdiscover-difference-mitosis-meiosis%252F%3B495%3B420\

Mitosis Video

• http://video.mit.edu/watch/lego-animation-of-mitosis-with-descriptive-titles-3077/

DNAStands for Deoxyribonucleic Acid

• Primary Function: to store and transmit the genetic information that tells cells whcih protiens to make and when to make them

• DNA is an organic compound made up or repeating subunits called nucleotides.

• Nucleotides have 3 parts:

• Sugar molecule

• Deoxyribose

• Phosphate Group

• Phosphorus

• Oxygen

• Nitrogen Bases

• Adenine (A)

• Cytosine (C)

• Guanine (G)

• Thymine(T)

VIdeo: https://answersingenesis.org/genetics//

• 2 types of Nitrogen Bases

• Purines

• Have 2 rings

• Adenine(A)

• Guanine(G)

• Pyrimdines

• Have 1 ring

• Cytosine(C)

• Thymine(T)

DNA Cont.• Base Pairings:

• Cytosine bonds with Guaning (C-G)

• Adenine bonds with Thymine (A-T)

• James Watson and Francis Crick built the 3D model or the double helix

• 2 nucleotide strands wrap around eachother to form a double spiral

• Enzymes involved in DNA replication:

• DNA Helicase

• Unwind and unzip the DNA

• Binding Proteins

• Hold open the replication fork

• DNA Primase

• Lay down the start and stop primers for the new strand

• DNA Polymerase

• Lays down one new nucleotide at a time

• DNA Ligase

• The glue that holds the new DNA strand together

• The Enzymes involved in DNA replictation

en.wikipedia.org

RNA• Stands for Ribonucleic Acid

• Responsible forthe movement of genetic information from the DNA in the nucleus to the site of protien synthesis in the cytosol

• A single sranded nucleic acid made up of repeating units

• Sugar molecule is ribose

• Thymine(T) relaced with URACIL(U)

A strand of RNAhttp://chemistry.tutorvista.com/biochemistry/nucleic-acids.html

RNA cont.

• 3 Forms of RNA

• Messenger RNA (mRNA)

• Function:

• Carries genetic info from the nucleus to the ribosome

• Transfer RNA (tRNA)

• Function:

• Binds to specific amino acids and helps form polypeptide chains (proteins)

• Ribosomal RNA (rRNA)

• Function:

• Makes up the ribosomes where proteins are made

Protein synthesis

• Protein Synthesis- The production of proteins

• The amount and kind of proteins produced in a cell determines the structure and function of the cell

• 2 Steps in Protein Synthesis

• Transcription:

• Makes mRNA from DNA

• Transcribe- to copy

• Translation:

• mRNA leaves the nucleus through pores in the nuclear membrane

• mRNA then migrates to a ribosome in the cytosol, the site of protein synthesishttp://

sciencevogel.wikispaces.com/file/view/Protein%20Synthesis

%20diagram.png/493016480/390x301/Protein

%20Synthesis%20diagram.png

Mutations/Disorders• Genetic Disorders:

• Genetic Traits and Disorders-

• Genes that control human traits can be mutated and then inherited by offspring

• Mutations-

• Definition- A change in DNA sequence that affects genetic info

• The result of some mutations are gentic disorders

• Inheritance- There are 4 main ways genetic disorders are passed....

• Single Gene Disorder

• The problem traits controlled by a single gene and are passed in a dominant/recessive manner

• Multifactoral Disorders

• These disorders result from mutations in multiple genes

• These disorders are difficult to study and treat

• EX. Alzheimer's Disease, Hypothyroidism

Karyotype showing the genetic disorder of Down Syndrome

http://learn.genetics.utah.edu/content/disorders/

chromosomal/down/images/trisomy21_karyotype.jpg

Mutations/Disorders continued

• Inheritance cont.

• Chromosomal Abnormality

• Entire chromosomes or large segments of chromosomes are missing, duplicated, or otherwise altered

• Nondisjunction-

• Failure of a chromosome to seperate from its homologue during meiosis

• One gamete receives an extra copy of a chromosome and the other gamete lacks the chromosome entirely

• Scientisits can use karyotypes to identify disorders caused by chromosomal abnormalities

• X-Linked Disorders

• Disorders in which the mutations or errors are in genes found on the X chromosomes

• Ex.- Hemophilia, Muscular Dystrophy

Review Questions

• What is the full name for DNA? Deoxyribonucleic Acid

• What two organelles can DNA be found in? Nucleus, Mitochandria

• What is the shape of DNA? Double Helix

• What is a Gene? A sequence of DNA passed on to offspring

• What are the two purines found in DNA? Adenine, Guanine

• What are the two phases of protein synthesis? Transcription, Translation

• What are the four types of chromosomal mutations?

• What is the gene that is expressed called?

• What is a mutation?

Answers

• What is the full name for DNA? Deoxyribonucleic Acid

• What two organelles can DNA be found in? Nucleus, Mitochandria

• What is the shape of DNA? Double Helix

• What is a Gene? A sequence of DNA passed on to offspring

• What are the two purines found in DNA? Adenine, Guanine

• What are the two phases of protein synthesis? Transcription, Translation

• What are the four types of chromosomal mutations? Deletions, Duplication, Insertion, Translocation

• What is the gene that is expressed called? Dominant

• What is a mutation? A change in the DNA sequence that effects genetic info