What keeps the two DNA strands separate during replication?
helicase
Are the 2 strands of DNA identical?
Before a cell divides, its DNA is replicated (duplicated.) If the two strands of a DNA molecule are separated, each can be used as a pattern or template to produce a complementary strand. Each template and its new complement together then form a new DNA double helix, identical to the original.
Are DNA strands complementary?
Due to the base pairing, the DNA strands are complementary to each other, run in opposite directions, and are called antiparallel strands.
How do you replicate DNA strands?
DNA replication occurs through the help of several enzymes. These enzymes “unzip” DNA molecules by breaking the hydrogen bonds that hold the two strands together. Each strand then serves as a template for a new complementary strand to be created. Complementary bases attach to one another (A-T and C-G).
What is complementary DNA sequence?
Reviewed on 3/29/2021. Complementary sequence: Nucleic acid sequence of bases that can form a double- stranded structure by matching base pairs. For example, the complementary sequence to C-A-T-G (where each letter stands for one of the bases in DNA) is G-T-A-C..
What base does cytosine always bind to?
guanine
Which model of base pairing is correct?
Rules of Base Pairing A with T: the purine adenine (A) always pairs with the pyrimidine thymine (T) C with G: the pyrimidine cytosine (C) always pairs with the purine guanine (G)
What happens when base pairs are mismatched?
Incorrectly paired nucleotides cause deformities in the secondary structure of the final DNA molecule. During mismatch repair, enzymes recognize and fix these deformities by removing the incorrectly paired nucleotide and replacing it with the correct nucleotide.
What happens when a base pair is deleted?
If one or two bases are deleted the translational frame is altered resulting in a garbled message and nonfunctional product. A deletion of three or more bases leave the reading frame intact. A deletion of one or more codons results in a protein missing one or more amino acids. This may be deleterious or not.
What are some possible results of base pair substitutions?
…to single base pairs, called base-pair substitutions. Many of these substitute an incorrect amino acid in the corresponding position in the encoded protein, and of these a large proportion result in altered protein function. Some base-pair substitutions produce a stop codon.
What are the two basic types of base pair substitutions?
Mutations may have a wide range of effects. Point mutations are those mutations that affect a single base pair. The most common nucleotide mutations are substitutions, in which one base is replaced by another. These substitutions can be of two types, either transitions or transversions.
How can base pair substitution result in a silent mutation?
How can a base-pair substitution result in a silent mutation? A change in a nucleotide pair may transform one codon into another that is translated into the same amino acid. Such a change is an example of a silent mutation, which has no observable effect on the phenotype.
Which type of mutation adds one or more base pairs?
insertion
Which type of mutation is responsible for new variations of a trait?
Which type of mutation is responsible for new variations of a trait? ali mutations other than 2. Which type of mutation results in abnormal amino acid sequence? silent mutations.
What type of mutation is shown in the copied sequence?
What type of mutation is shown in the copied sequence? The mutation that occurred in the copied DNA sequence will be present in all the cells of the body.