Categorie: Tutti - dna - chromosomes - diseases - bonds

da Gilmar Zambrano mancano 11 mesi

89

DNA

DNA, the molecule that carries genetic information, consists of two strands held together by hydrogen bonds. The structure of DNA was elucidated through X-ray diffraction studies, revealing its helical shape.

DNA

which are

autosomal diseases

Because they are paired

they all

can be observed

karyotyping

affects

several genes

diseases and/or syndromes
like

Klinefelter

sex chromosome

long

legs

arms

sterile male

Down syndrome

chromosome 21

facial features

short neck

in learning

Turner

one sex chromosome

characterized by

short structure

sterile female

two hydrogen bonds

three hydrogen bonds

to separate

unify together

guanine
adenine
cytosine
complement each other
keeping the two stands

together

based on the work of

Rosalind Frank

Edwin Cargaff

base complementary
"DNA of any species

Crystal structure of DNA

X-Ray Diffraction

helical shape of the DNA

equal amounts

DNA

Nucleotides

phosphate group
attaches to

5' carbon of sugar

3' to next carbon

pattern of sugar-phosphate

stable structure

held together

ester bonds

base pairs

single ring

double ring

Made of

4 oxygen atoms

1 phosphorus atom

deoxyribose
forms

Cyclic

used in DNA

Beta deoxyribose in DNA

Linear

Consists of

5 carbon atoms

1 oxygen atom

10 hydrogen atoms

held by

phosphodiester bonds

Pentose sugar

Pentagonal ring shape

Nitrogenous base
Complementary

Pyrimidines

Single-ring

Cytosine

Thymine

Purines

Double ring

Guanine

Adenine

Codes

codon
64 possible codons
codes for a specific amino acid

encoded by more than one codon

steps a code goes through
transcription

RNA processing

Translation

Protein modification

Transport

cells/outside cells

chain is folded/modified

proteins are assembled

modifying mRNA molecule

messenger mRNA

RNA polymerase

genetics codes in humans
the same

everyone has codes for arms

sequences of nucleotides
genetic instructions for organism

cellular machinery

ribosomes

produce proteins

chains of amino acids

Interesting Facts

Throughout evolution
over 500 DNA codes
6 ft in each cell
30,000 genes
3 billion base pairs
Human genome
99% identical
not all DNA is genes
only 2% are genes

"Junk DNA"

epigenetics

DNA can be Modified

DNA makes RNA
RNA makes protein

no life

Don't have DNA
Other types of blood

have DNA

DNA...
Undergoes tiny mutations daily
can be two sets in 1 person

chimerism

Capable of change

Frequency change by mutagens

randomly during repliction

from Various Sources
Hair and skin cells
can be damaged
Radiation
Chemicals

Replication

2 DNA molecules
2 strands each
Semiconservative
One strand

newly formed

Other strand

old

Enzymes
Helicase

hydrogen bonds

helix is separated

DNA Polymerase

addition of nucleotides

growing strand

Through
Transcription

RNA

from DNA

similar to DNA

with some differences

single stranded

different sugar

ribose

another nucleoside

uracil

thymine

replication fork
multiple
Inside the nucleus
where replication can occur
S-phase

Nucleus of cell in eukaryotes

Hereditary material

which was determined by
Avery
McCarthy
MacLeopd

Mitosis and Meiosis

DNA is replicated and distributed
make new cells

DNA stay alive

it passes on to next generations

Mitosis creates to identical cells
DNA is not degraded

No recovering dead DNA

Mutations

can occur in
gene

occurs by errors in DNA replication

nucleotide

is altered

which its influence is low

some diseases

can occur

Huntington Syndrome

Cystic Fibrosis

hemophilia

sex-linked diseases

sickle cell anemia

chromosomes

alterations

number

structure

sequence in the DNA
mutations can be inherited
change of the proteins

can occur in DNA replication

Double helix

proposed by
Watson
James Creek

Prokaryotic DNA

is
not tightly packed

not bound with proteins

no chromatin structure

nucleoid-associated proteins.

small and less complex
single circular chromosome

lacks transposons

unlike eukaryotic DNA

mobile DNA segments

not much DNA

doesn't contain introns

non-coding regions

coding regions

making proteins

double helix

double-stranded

Circular DNA

found in cytoplasm

found in plasmids