Crowe questions Flashcards
Glucose isomerase is an enzyme used to convert glucose to fructose. Why is it known as an isomerase?
Fructose is an isomer of glucose
Give an advantage of immobilizing an enzyme
- Doesn’t contaminate product;
- Can be re-used
- Is more stable
What is the role of a vector?
Transfers genes from one organism to another
What is the role of DNA ligase in production of recombiant DNA?
Forms phosphodiester bonds between nucleotides.
What is the importance of reducing chromosome number when the cell divides by mitosis?
Allows later fertilization when cells fuse, restoring the original diploid number.
What are the differences between mitosis and meiosis?
- In meiosis, homologous chromosomes associate in pairs; in mitosis chromosomes are independent and don’t pair
- Crossing-over occurs in meiosis, not in mitosis
- Two divisions resulting in 4 offspring cells in meiosis. In mitosis there is one, producing 2 daughter cells;
- In meiosis the product is genetically different. In mitosis it is genetically identical
Other than form, suggest other sources of evidence used by scientists which suggest two animals are of different genera.
Fossil record
Evolutionary history
Biochemical differences
Give an advantage of DNA having two strands.
Stability, replication, to protect bases.
What does an RNA nucleotide consist of?
Base
Ribose
Phosphate
Why is DNA replication semi-conservative?
Daughter DNA contains one new strand and one original strand.
What is RNA polymerase’s role during transcription?
Join RNA nucleotides to form a strand a backbone, forms phosphodiester bonds, making pre-mRNA
What is a marker gene?
Gene coding for easily identifiable product, e.g antibiotic resistance gene; Allows scientists to see if bacteria contain transferred gene.
Why might resistance genes not be appropriate for marker genes?
Gene may be transferred to harmful bacterium; causing resistance to antibiotic, preventing it’s use.
What is a primer?
Single strand of DNA; Bases complementary to part of DNA to be copied;
Marks section being copied and allows attachment of polymerase;
What is a DNA marker?
Fragment of DNA of known size
