Anatomy chapter 22 DNA

DNA

It replicates to be passed on to the next generation. undergoes mutations to provide genetic diversity. stores information. Bases ATCG

double strand

DNA has a ______ helix

nucleotides

DNA is composed of repeating ______ made of pentose sugar, phosphate, and nitrogenous base.

Sugar and phosphate

_________ make up the backbone of DNA

bases

______ make up the “rungs” of DNA

cytosine

guanine pairs with

thymine or uracil

adenine pairs with

DNA polymerase

Complementary nucleotides are added to each strand by ______

semiconservative replication

Each new double-stranded helix is made of 1 new strand and one old strand

RNA

composed of repeating nucleotides. Sugar phosphate backbone. bases ACGU

single stranded

RNA is ______

Messenger RNA

carries genetic information from DNA to the ribosomes

Ribosomal RNA

joins with proteins to form ribosomes.

Transfer RNA

transfers amino acids to a ribosome where they are added to a forming protein.

nucleus

DNA is located in the ____

cytoplasm and nucleus

RNA is located in the _______

amino acids

proteins are composed of subunits called

shape

The sequence of amino acids determines the ______ of the protein.

ribosomes

proteins are synthesized at the ______

hormones, enzymes, and transport.

•Proteins are important for diverse functions in the body including

Transcription

DNA is read to make a mRNA in the nucleus. •mRNA is made from a DNA template. mRNA is processed before leaving the nucleus. mRNA moves to the ribosomes to be read.

Translation

mRNA is read to make a protein in the cytoplasm. 3 steps initiation, elongation, and termination.

Bases

• act as a code for amino acids used in translation.

codon

Every 3 bases of the mRNA is called a ______; a typical ______specifies a particular amino acid in translation.

initiation

mRNA binds to the small ribosomal subunit and causes the 2 ribosomal units to associate

Elongation

polypeptide lengthens. tRNA picks up an amino acid, has an anticodon that is complementary to the codon on the mRNA, tRNA anticodon binds to the codon and drops off an amino acid to the growing polypeptide.

termination

a stop codon on the mRNA causes the ribosome to fall off the mRNA

Genetic engineering

altering DNA in bacteria, viruses, plants, and animal cells through recombinant DNA technology

Recombinant DNA

contains DNA from 2 or more different sources

Transgenic organisms

organisms that have a foreign gene inserted into them

Biotechnology

using natural biological systems to create a product or to achieve an end desired by humans

Polymerase chain reaction

is used to clone small pieces of DNA. It is important for amplifying DNA for analysis such as in DNA fingerprinting

DNA fingerprinting

Fragments are separated by their charge/size ratios

Results in a distinctive pattern for each individual

Often used for paternity testing, or to identify an individual at a crime scene or unknown body remains

Recombinant DNA

contains DNA from 2 or more different sources that allows genes to be cloned

Restriction enzyme

is used to cut the vector (plasmid) and the human DNA with the insulin gene.

DNA ligase

seals together the insulin gene and the plasmid.

Bacterial cells

take up plasmid during gene cloning, the gene is copied, and the product can be made

Gene therapy

insertion of genetic material into human cells to treat a disorder

ex vivo therapy

cells are removed from the body for treatment, and then reintroduced back into the body.

in vivo therapy

the vector is introduced directly into the body.

cancer

•Gene therapy has been most successful in treating ____

Bioinformatics

the application of computer technologies to study the genome

transgenic organisms

organisms that have a had a foreign gene inserted into them

Xenotransplantation

the use of animal organs instead of human organs in transplant patients

Gene pharming

production of pharmaceuticals in the milk of farm animals

3 billion, 25,000

The human genome consists of about _______ bases and_______ genes.

Functional genomics

Understanding how the 25,000 genes function. Understanding the function of gene deserts (25% of DNA is comprised of these regions)

Comparative genomics

Help understand how species have evolved. Comparing genomes may help identify base sequences that cause human illness. Help in our understanding of gene regulation

Proteomics

the study of the structure, function, and interactions of cell proteins

DNA Sequencing

The order of nucleotides in a DNA sequence is determined. Now performed using dyes attached to nucleotides, with a laser and computerized machine to determine sequence

One end of the RNA is capped, introns are removed, A poly-A tail is added.

Modifications of mRNA

phosphoric acid, pentose sugar, nitrogen-containing base

structure of nucleotide

replicate, store info, undergo change

aspects of DNA 3 things

20

how many amino acids are found in proteins

DNA polymerase

DNA polymerase

Complementary nucleotides are added to each strand by

RNA polymerase

what enzyme is responsible for transcribing RNA

cloning

is the production of genetically identical copies of DNA, cells, and organisms.

bioinformatics

is the application of computer technologies to the study of the genome

gene therapy

is the insertion of genetic material into the human cells for the treatment of a disorder. used to cure cardiovascular disease and cancer

reverse transcriptase

can be used to make a DNA copy of mRNA

genome editing

the targeting of specific sequences in the DNA for removal or replacement

complementary DNA

does not contain introns. The recombinant cells make many of themselves containing the new gene through mitosis and each new cell will make the product coded for the new gene.

vector

by which the gene of interest will be introduced into a host cell such as a bacterium

plasmid

small accessory rings of DNA found in the bacteria that often hold genes for antibiotic resistance.

transcription factors

dna binding proteins

pretransitional control

in the nucleus; the DNA is made available to transcription factors and enzymes

Transcription control

in the nucleus; the degree in which a gene is transcribed into mRNA dtermines the amount of gene product. transcription factors.

posttranscription control

in the nucleus; involves mRNA processing and how fast mRNA leaves the nucleus

translational control

in the cytoplasm; affects when translation begins and how long it continues; includes inactivation and degradation of mRNA

posttranslational control

in the cytoplasm; occurs after protein synthesis

polyribosome

multiple ribososomes

rRNA and proteins

ribosomes are composed of

introns

intragene segments that do not code for functional protein

exons

ultimately expressed. result in a protein product.

APE

ribosome contains binding sites

A

acceptor or arrival

P

polypeptide

E

exit

anticodon

3 base sequences on the tRNA that will complementarily base pair with the codons of mRNA

3’ 5’

a double helix will have carbon ends