molecules that form the building blocks of (DNA and RNA) 

-carry packets of energy and participate in cell signaling 

-Helix

-Connectors

-nucleotides

*Phosphoric Acid

*Deoxyribose

*Nitrogenous bases, which means they have

-Adenine

-Thymine

-Guanine

-Cytosine

(A hooks up with T)

(G hooks up with C)

-a set of 3 nitrogenous bases  on the DNA code for a specific amino acid (Codon)

-these amino acids are strung together in orderto make the protein

-the recipe is transcribed in the nucleus & brought out in the ER for production

Transcription

(explain how this works)

*DNA NEVER leaves the nucleus

*A messenger RNA copy of the gene is sent out to the cytoplasm.

RNA polymerase -->(attaches to) --> DNA

~Transcription takes place~

messanger RNA(a copy of the DNA) is sent out

-removing some parts = Introns

-keeping some parts = Exons

-adding somes bases

-cutting the mRNA abd splicing it back together

happens in:

The cytoplasm

-mRNA acts as a pattern telling the cell how to line up amino acids to form a protein

-amino acids are carried into position by transfer RNA molecules.

-Ribosomes made of Ribosomal RNA fasten the amino acids together make a protein.

-carries the amino acid

-lines up by matching it's anticodon to the mRNA's codon

*moves along the mRNA

*moving transfers RNA's into position

(kinda like a conductor)

*it connects amino acids that mRNA's have carried into position

-linear thread of DNA

-visible during cell divison

23 pairs, 1 sex pair

-cells reproduce by duplicating the chromosomes and dividing into two

*chromosomes duplicate

*one pair goes to each daughter cell on the 1st division

-then-

*one chromosome of each pair goes to the daughter cell in the 2nd division

**You now have a gamete that has only one copy of each chromosome and it is Unique!**

Broader gene pool!

-this is when chromosome pairs line up during meiosis and they can exchange ends

(kids lining up, exchanging gloves)

-Each of the 4 resulting gametes will have a different combination of genes.

-One set from Mom

-One set from Dad

Genotype vs Phenotype

explain the difference

Genotype = a person's genetic material

Phenotype = a person's physical characteristics (what you look like)

Genotype = a person's genetic material

Phenotype = a person's physical characteristics (what you look like)

this is how the gene is expressed in phenotype

(mild to severe)

-one of all possible forms of the gene

-alternate forms of the gene

Dominant traits = are expressed in the phenotype

Recessive traits = are not expressed but may be passed on

 one of several ways that a trait or disorder can be passed down through families.

If a disease is autosomal dominant, it means you only need to get the abnormal gene from one parent in order for you to inherit the disease, you have a 50% chance

Examples of Autosomal

Dominant Disorders

Marfan =

-long arm of chromosome 15

-connective tissue disorder

-affects skeleton, cardiac & eyes

--aortic aneurysm & valve problems

Neurofibromatosis

*neurogenic tumors from Schwann cells

*defect in tumor supressing

*dark pigment of skin & eyes

*disfiguring tumors

 is the result of a single mutated gene.

this person doesnt have it/show it but can pass it on

*Phenylketonuria (PKU) = lack of enzyme that converst phenylalanine to tyrosine

(mental retardation, microcephaly, impaired neurological development)

-Most are mandatory screened for this.

Tays-Sachs  = lysosomal storage disease

-weakness, muscle flaccidity,seizures,blindness and death by age 4

-common in  eastern european jews

always a carrier on the X chromosome

*if mom carries it she doesnt pass it on to her daughter but will to her son*

*Fragile X

-mental retardation

-facial abnormalities

-hyper extensibe joints

*Hemophilia

-bleeding disorders

*Dupication = Mosaicism-accidental duplication or combination of a chromosome

*Number

-Down Syndrome (Trisomy 21)

-Turner Syndrome (Monosomy X)

-Klinefelter (Polysomy X)