CHAPTER 6: GENES AND DNA
OBJECTIVE: Students will reconize how biological traits are passed on to successive generations.
SECTION 1 Vocabulary: WHAT DOES DNA LOOK LIKE?
* DNA- deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that a living thing inherites and needs to live.
* NUCLEOTIDES- a subunit that consists of a sugar, phosphate, and a nitrogenous base.
* NITROGENOUS BASE- the nucleotides that make up the rungs of DNA, the four nitrogenous bases are adenine, thymine, guanine, and cytosine.
SECTION 1 Summary: WHAT DOES DNA LOOK LIKE?
- The dna molecule looks like a twisted ladder. The two halves are long strings of nucleotides. The rungs are complementary pairs of bases.
- Because each base has a complementary base, DNA can be replicated accuratly.
- A colmplementary strand is the new strand of DNA atatched to the old strand of DNA.
-Each strand of DNA is made up of the four nitrogenous bases, adenine, thymine, guanine, and cytosine.
- Erwin Chargaff found out that if adenine and tymine can only be paired because the amount where equal. He also found that only cytosine and guanine cna pair together.
- Rosalind Franklin questioned what DNA might look like. to find this out, Frankiln used the process known as X-ray difffusion to make images of the DNA. She then found that DNA had a spiral like shape.
- James Watson and Francis Crick then used Franklin's images to make a model of DNA. That is how we know that the structure of DNA is in a spiral shape.
SECTION 1 Vocabulary: WHAT DOES DNA LOOK LIKE?
* DNA- deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that a living thing inherites and needs to live.
* NUCLEOTIDES- a subunit that consists of a sugar, phosphate, and a nitrogenous base.
* NITROGENOUS BASE- the nucleotides that make up the rungs of DNA, the four nitrogenous bases are adenine, thymine, guanine, and cytosine.
SECTION 1 Summary: WHAT DOES DNA LOOK LIKE?
- The dna molecule looks like a twisted ladder. The two halves are long strings of nucleotides. The rungs are complementary pairs of bases.
- Because each base has a complementary base, DNA can be replicated accuratly.
- A colmplementary strand is the new strand of DNA atatched to the old strand of DNA.
-Each strand of DNA is made up of the four nitrogenous bases, adenine, thymine, guanine, and cytosine.
- Erwin Chargaff found out that if adenine and tymine can only be paired because the amount where equal. He also found that only cytosine and guanine cna pair together.
- Rosalind Franklin questioned what DNA might look like. to find this out, Frankiln used the process known as X-ray difffusion to make images of the DNA. She then found that DNA had a spiral like shape.
- James Watson and Francis Crick then used Franklin's images to make a model of DNA. That is how we know that the structure of DNA is in a spiral shape.
DNA
D.N.A stands for deoxyribonucleic acid. DNA is a spiral in shape and is a double helix. It contains the information that determines the traits of a living thing inherites and needs to live.
SECTION 2 Vocabulary: HOW DNA WORKS
* PROTEIN- a molecule that is made up of amina acids and that is needed to regulate processes in the body.
* AMINO ACID- any one of about 20 differences organic molecules that are used to make proteins.
* MUTATIONS- a change in the nucleotide-base sequence of a gene or DNA molecule.
* RNA- ribonucleic acid, a molecule that is present in all living cells and that plays the role in protein production.
* RIBOSOME- a cell organelle composed of RNA and protein; the site of protein synthesis.
* GENETIC ENGINEERING- when scientists can minipulate individual genes withen organisms.
SECTION 2 Summary: HOW DNA WORKS
- A gene is a set of instructions for assembling a protein. DNA is the molecular carrier of these genetic instructions.
- Every organism has DNA within its cells.
- Within each gene, each group of three bases codes for one amino acid. A sequence of amino acids is linked to make proteins.
- Proteins are fundemental to the function of cells and the expressionof traits.
- Proteins are assembled within cytoplasm through multi-step process thatis assisted by several forms of DNA.
- Genes can be mutated when the order of the bases is changed. Three main types of mutations are possible: insertion, deletion, and substitution.
- When insertion happens, DNA adds a base. When deletion happens, DNA misses one of the bases. When substitution happens, DNA replaces one of the bases.
- Genetic knowledge has many pratical uses. Some applications of genetic knowledge are controversial.
* PROTEIN- a molecule that is made up of amina acids and that is needed to regulate processes in the body.
* AMINO ACID- any one of about 20 differences organic molecules that are used to make proteins.
* MUTATIONS- a change in the nucleotide-base sequence of a gene or DNA molecule.
* RNA- ribonucleic acid, a molecule that is present in all living cells and that plays the role in protein production.
* RIBOSOME- a cell organelle composed of RNA and protein; the site of protein synthesis.
* GENETIC ENGINEERING- when scientists can minipulate individual genes withen organisms.
SECTION 2 Summary: HOW DNA WORKS
- A gene is a set of instructions for assembling a protein. DNA is the molecular carrier of these genetic instructions.
- Every organism has DNA within its cells.
- Within each gene, each group of three bases codes for one amino acid. A sequence of amino acids is linked to make proteins.
- Proteins are fundemental to the function of cells and the expressionof traits.
- Proteins are assembled within cytoplasm through multi-step process thatis assisted by several forms of DNA.
- Genes can be mutated when the order of the bases is changed. Three main types of mutations are possible: insertion, deletion, and substitution.
- When insertion happens, DNA adds a base. When deletion happens, DNA misses one of the bases. When substitution happens, DNA replaces one of the bases.
- Genetic knowledge has many pratical uses. Some applications of genetic knowledge are controversial.
DNA MUTATION
D.N.A stands for deoxyribonucleic acid. DNA is a spiral in shape and is a double helix. It contains the information that determines the traits of a living thing inherites and needs to live.
JAMES WATSON AND FRANCIS CRICK
James Watson and Francis Crick made the model of DNA using Rosalind Franklin's X-ray diffraction images and Erwin Chargaff's rules. According to Franklin's images, DNA had a spiral shape. Watson and Crick used these images to build a model of DNA.