bio-DNA quiz

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Genetics

the science that studies how characteristics (or traits) get passed from one parent to offspring (called inheritance)

what year(s) did scientists determine that DNA was the molecule that stored genetic information

the 1920's

DNA stands for

Deoxyribonucleic acid

DNA is composed of...

a string of nucleotides

DNA strings are made of 3 parts…

5-carbon sugar called deoxyribose, A phosphate group, A nitrogen base (4 choices; Adenine, Guanine, Cytosine, and Thymine)

Edwin Chargaff

determined that A=T & G=C, base pairing system

Rosalind Franklin

used an X-ray to show that 2 DNA strands were twisted

Francis Crick & James Watson

Used Franklin’s picture to create the first model of DNA

Adenine pairs with…

thymine

Guanine pairs with…

cytosine

The shape of DNA

double helix

double helix

\-composed of alternating deoxyribose sugar and phosphate groups

\-commonly called the “sugar-phosphate backbone”

\-looks like a twisted ladder

\-The rungs of the ladder are made of nitrogen bases

\-WEAK SO THAT THEY CAN BREAK AND COME BACK TOGETHER

gene

a segment of DNA that codes for the protein, thereby causing a genetic characteristic of a trait, ike Hair color, eye color, or height

cells are constantly...

growing and dividing, which must be accomplished without breaking the DNA strands

In order to protect the DNA….

it is tightly coiled around proteins called **histones** and condensed into **chromosomes**

DNA can....

tell many things about a person and genetic differences between people are very important so diseases are not as deadly

DNA replication

when a cell divides, DNA must be copied, requires the strands to be unwound first

replication fork

\-After the DNA is unwound from the histones, an enzyme called helicase “unzips” the two strands of DNA

\-This location is known as the replication fork.

DNA polymerase

brings nucleotides to match one of the DNA strands (known as the parent strand)

Stem cell(s)

a cell that has not been assigned a part yet

DNA replication is a semi-conservative process because....?

only half of each parent strand remains in the new DNA molecule

SUMMARY OF DNA REPLICATION:

To make it easy to move DNA without damage, it is wrapped around __**histones**__ and condensed into __**chromosomes**__. To copy the DNA (called DNA __**replication**__), enzymes separate the two strands and use one side as the blueprint to make a __**complementary**__ strand.

SUMMARY OF DNA:

DNA is the molecule that stores genetic information for cells. It is shaped like a double helix with bases on the inside. These match in pairs with A bonding with T and C bonding with G

histone

a group of basic proteins that help protect DNA

chromosome

\-a structure of nucleic acids and protein

\-found in the __nucleus__ of most living cells

\-carries genetic information in the form of genes

complementary DNA strands

two strands of DNA with corresponding bases/chains (google definition: (either of the two chains that make up a double helix of DNA, with corresponding positions on the two chains being composed of a pair of complementary bases)