Nandna Flashcards
What is the structure of a nucleotide?
A nucleotide consists of a sugar, a phosphate group, and a nitrogenous base.
How are DNA and RNA nucleotides different?
DNA nucleotides contain deoxyribose sugar, while RNA nucleotides contain ribose sugar.
What are the differences between purines and pyrimidines?
Purines have a double-ring structure (adenine and guanine), while pyrimidines have a single-ring structure (cytosine, thymine, and uracil).
What is the structure of the DNA double helix?
The DNA double helix consists of two strands that wind around each other, held together by complementary base pairing.
How do DNA and RNA differ in function?
DNA stores genetic information, while RNA plays a role in protein synthesis and gene expression.
What is complementary base pairing, and why is it important?
Complementary base pairing is the specific pairing of adenine with thymine and cytosine with guanine, which is crucial for DNA replication and transcription.
What are the steps of semi-conservative DNA replication?
The steps include unwinding the DNA helix, complementary base pairing, and joining the new nucleotides to form two identical DNA molecules.
What enzymes are involved in DNA replication and their roles?
Key enzymes include helicase (unwinds DNA), DNA polymerase (adds nucleotides), and ligase (joins Okazaki fragments).
What are the roles of mRNA, tRNA, and RNA in protein synthesis?
mRNA carries the genetic code, tRNA brings amino acids to the ribosome, and rRNA is a component of the ribosome.
What happens during transcription and translation?
During transcription, DNA is transcribed into mRNA; during translation, mRNA is translated into a polypeptide chain (protein).
What is ATP, and how is it used as an energy source?
ATP (adenosine triphosphate) is the primary energy carrier in cells, providing energy for various biochemical processes.
How is ATP synthesized and broken down?
ATP is synthesized through cellular respiration and photosynthesis, and it is broken down into ADP and inorganic phosphate to release energy.
