oral revalida Flashcards
What is the breakage of the backbone of long-chain macromolecules, reducing size and viscosity?
main-chain scission
What is the formation of bonds between macromolecules, increasing viscosity?
cross-linking
What are the three main effects of main-chain scission?
- Reduced mechanical strength
- changes in physical properties
- loss of functionality.
Cross linking could result histones and actin (toxins)
INTINDIHI
What is a common cross-linking example?
DNA-protein
What is the disruption of a single chemical bond in DNA, causing molecular malfunction.
point lesion
Point lesion is Not detectable, but can cause a minor modification of molecule, which in turn cause it to malfunction within cell
INTINDIHI
What are some effects of point lesions?
- Single-strand breaks
- double-strand breaks
- base damage
- DNA-protein cross-linking
What are the usual pathological effects of point lesions?
- Mutation
- cell death
- tumor formation
What are purines?
Adenine and guanine
What is the breakdown of molecules to release energy?
catabolism
What are pyrimidines?
Thymine and cytosine (in DNA)
Cytosine and Uracil (in RNA)
What is the synthesis of macromolecules from smaller molecules using energy.
anabolism
What is the function of proteins?
- Provide structure and support,
- Produce enzymes, hormones, and antibodies.
What is protein?
A long-chain macromolecules that consists of linear sequence of amino acids connected by peptide bond
What is the responsibility of transfer RNA (tRNA)?
Brings the correct amino acids to ribosomes during translation.
What is the responsibility of messenger RNA (mRNA)?
Carries genetic information from DNA to ribosomes for protein synthesis.
Proten Synthesis
- Proteins are manufactured by translation of genetic code from transfer RNA (tRNA)
- Code is transferred to messenger RNA (mRNA)
- The information carried by mRNA is transcribed to a newly synthesized protein
other information about PROTEIN
- Radiation damage to any of these macromolecules may result in cell death/ late stochastic effect
- Proteins are continuously synthesized throughout cell cycle and occur in much more abundance than nucleic acid
- Proteins are less radiosensitive than nucleic acids. Recovery and repair are possible.
What is DNA?
It is considered the most important molecule.
It carries genetic information
It is the most radiosensitive molecule.
What happens during the G1 phase of interphase?
Growth and replication of organelles occur, protein synthesis, and metabolic functions.
what is the initial phase in DNA synthesis?
G1 phase
What happens during the S phase of interphase?
synthesis of DNA ladder splits, becomes single-chained with no base pairing
and chromosome replication
What happens in the G2 phase of interphase?
growth continues, protein synthesis, and preparation for mitosis (M phase).
assembly of spindle begins, base paring occurs, resulting in duplicate two DNA daughter molecules
