S7: Chapter 4.4: DNA study questions

What are the base pairing rules?

A and T bind together and C and G bind together

Explain the process of DNA replication.

During DNA replication, a DNA molecule "unzips" between its paired bases. New bases pair with the bases on each old strand. As a result, two identical DNA strands form.

How can mutations affect an organism?

Mutations can cause a cell to produce an incorrect protein during protein synthesis. As a result the organism's trait, or phenotype, may be different from what it normally would have been. Mutations can either be helpful or harmful to an organism. Whether a mutation is harmful or not depends partly on the environment. An example of a harmful mutation is the production of a white lemur in the wild. The lemur's white color would make it more visible and thus easier for its predators to find. However, if the white lemur lived in a zoo it would not affect the lemur. A mutation that improves an organism's chances for survival and reproduction are helpful mutations. For example, antibiotic resistance in bacteria. Gene mutations have enabled some kinds of bacteria to become resistant to certain antibiotics thus improving the bacteria's ability to survive and reproduce.

What is the role of the nucleus in protein synthesis?

The nucleus is the place when protein synthesis begins. To make a protein, mRNA copies information from DNA in the nucleus.

What are the different kinds of RNA and what do they do specifically?

Two types of RNA involved in protein synthesis are 1. Messenger RNA (mRNA) which copies the coded message from the DNA in the nucleus and carries the message to the ribosome in the cytoplasm. 2. Transfer RNA (tRNA), carries amino acids to the ribosome and adds them to the growing protein.

Where in a cell is DNA found?

nucleus

A segment of DNA that codes for a protein is called a ____________________?

gene

When does DNA replication process occur in the cell cycle?

mitosis

What is the difference between DNA base pairs and RNA base pairs?

DNA base pairs = A-T and C-G RNA base pairs = A-U (uracil) and c-G

Explain the step by step process of protein synthesis.

1. A copy of the gene (DNA) is made (called mRNA). The first step is a coded message in DNA is copied when a molecule of messenger RNA is formed. 2. MRNA then leaves the nucleus and carries the code into the cytoplasm. In the cytoplasm, mRNA attaches to a ribosome. On the ribosome, the mRNA provides the code for the protein molecule that will form. During protein synthesis, the ribosome moves along the mRNA strand. 3. The message is read by tRNA which attach to the mRNA. The bases on the tRNA "read" the message by pairing up three-letter codes to bases on the mRNA. The molecules of tRNA carry specific amino acids. The amino acids link in a chain. The order of the amino acids in the chain is determined by the order of the three-letter codes on the mRNA. 4. Each tRNA brings the correct amino acid to the molecule and a specific protein is made.

What 4 bases make up DNA molecules?

Adenine, guanine, cytosine, thymine.

What is the difference between an amino acid and a protein?

Amino acids are molecules linked together to form proteins.

What is the purpose of DNA replication?

DNA replication ensures that each daughter cell will have the genetic information it needs to carry out its activities.

What is the structure of DNA?

DNA stands for deoxyribonucleic acid. DNA found in the chromosomes. It is made up of molecules called nucleotides. i. The two side of the DNA ladder are made up of sugars and phosphates. Each rung of the DNA ladder is made up of a pair of nitrogen bases .The four nitrogen bases are: adenine, thymine, guanine, cytosine. The bases on one side of the ladder pair with the pairs with the other side and Adenine pairs with thymine.

What happens during protein synthesis?

During protein synthesis,the cell uses information from a gene on a chromosome to produce a specific protein. Protein synthesis takes place on the ribosomes in the cytoplasm of a cell. `

What is the basic structure of a nucleotide?

Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C). The order of these bases is what determines DNA's instructions, or genetic code.

Describe the shape of a DNA molecule.

Long, twisted zipper or a double helix

What is the role of mRNA in the protein synthesis?

Messenger RNA (mRNA) brings coded message from the DNA in the nucleus and carries the message to the ribosome in the cytoplasm.

Who were the three scientists that help to discover and figure out the structure of DNA?

Rosalind Franklin discovered that DNA was in a spiral form, James Watson and Francis Crick figure out the structure of DNA.

What are the different types of mutations?

Some mutations are the result of small changes in an organism's hereditary material. For example, a single base may be substituted for another, or one or more bases may be removed from a section of DNA. This type of mutation can occur during the DNA replication process. Other mutations may occur when chromosomes don't separate correctly during meiosis. When this type of mutation occurs, a cell can end up with too many or too few chromosomes. The cell could also end up with extra segments of chromosomes.

What is the role of the DNA in protein synthesis?

The DNA molecule serves as a "pattern" for making mRNA. The DNA molecule unzips between base pairs. RNA bases match up along one of the DNA strands. The genetic information in the DNA is transferred to the mRNA strand.

What are the effects of mutations?

The effects of mutation are either harmful to an organism or helpful, and others are neither harmful nor helpful. A mutation is harmful to an organism if it reduces the organism's chance for survival and reproduction. A mutation is helpful to an organism if it improves an organism's chances for survival and reproduction. Whether a mutation is harmful or not depends partly on the organism's environment.

What determines what type of protein will be made?

The genetic code determines what type of protein will be made.

What does a gene code for?

The order of the nitrogen bases along a gene forms a genetic code that specifies what type of protein will be produced.

What forms the genetic code?

The order of the nitrogen bases along a gene forms a genetic code that specifies what type of protein will be produced. In the genetic code, a group of three DNA bases codes for one specific amino acid. The order of the 3-base code units determines the order in which amino acids are put together to form a protein.

Why is the double helix shape in DNA important?

The patterns of nucleotides "tell" your cells to make proteins. DNA tells your cells to make thousands of proteins. A part of DNA which makes a certain protein is called a Gene. All these proteins made by genes determine what you look like.

How does a cell produce proteins?

The production of proteins is called protein synthesis. During protein synthesis, the cell uses information from a gene on a chromosome to produce a specific protein.`

What is the relationship between a gene, a DNA molecule, and a protein?

The relationships between a DNA and a gene is to produce specific proteins. DNA molecule is made up of 4 different nitrogen bases - adenine, thymine, guanine, and cytosine. The bases form the rungs on the DNA ladder. A gene is a section of a DNA molecule that contains the information to code for one specific protein. The gene contains the code that determines the structure of a protein. The order of the nitrogen bases along a gene forms a genetic code that specifies what type of protein will be produced.

What are the steps of DNA replication?

There are 3 steps: 1. Enzyme breaks bond between bases (unzipping of the strand) and strands separate. 2. New bases (found in cytoplasm) match up with the old strand 3. Sugar and phosphate form the sides of each new strand. (1 piece of NDA becomes 2 - each piece has 1 old strand and 1 new strand.)

What is the role of tRNA in the protein synthesis?

Transfer RNA (tRNA), carries amino acids to the ribosome and adds them to the growing protein.

What is the role of amino acids in the protein synthesis?

tRNA carries specific amino acids to the ribosome and attaches to the mRNA. The protein chain grows as each amino acid is attached.

The order of nitrogen bases determines the type of _____________________ that is assembled?

the sequence of amino acids