DNA, RNA, ATP, Water and Inorganic ions Flashcards
DNA structure
double stranded, antiparallel, double helix, ladder, two polynucleotide chains
what are DNA monomers called
repeating units called nucleotides
what are nucleosides made up of
= deoxyribose + base
what bond joins deoxyribose and base
ß-N-glycosidic bond
what are DNA nucleotides made up of
=deoxyribose + base + phosphate
bond between deoxyribose and phosphate
covalent phosphodiester bond
what reaction joins nucleotides
condensation reaction
what are the bonds between the nitrogenous bases
3 hydrogen bonds between CG
2 hydrogen bonds between AT
which bases are purines and how many rings
2 rings
A and G
which bases are pyrimidines and how many rings
1 ring
C and T
which bases are complementary pairings
AT and CG
why do AT and CG pair together
so that the strands are three rings apart
what type of sugar is deoxyribose and why
pentose sugar
contains 5 carbons
what does RNA stand for
ribonucleic acid
what does DNA stand for
deoxyribonucleic acid
difference between RNA and DNA
RNA shorter single stranded so no hydrogen bonds uracil replaces thymine in DNA contains ribose instead of deoxyribose
functions of RNA
information carrying molecules for protein synthesis
transfers genetic information from DNA to ribosomes
what are RNA nucleotides made up of
= phosphate + ribose + base
what does ATP stand for
adenosine triphosphate
what is ATP made up of
pentose sugar (ribose) nitrogenous base (adenine) three phosphate groups
what does ATP do
release energy at required amounts
equation for ATP
ATP + water = ADP + Pi (+ energy)
what reaction breaks the bonds between phosphate groups and the catalyst
hydrolysis breaks the weak bonds
ATP hydrolase
what can Pi be used for
phosphorylate other compounds making them more reactive
which places have a high concentration of mitochondria
muscles for movement
liver
villi in small intestine (active transport)
roots (active transport)
why do such places contain a higher concentration of mitochondria
produces ATP as they require more energy
uses of energy for living organisms (6)
metabolism movement repair and division of cells active transport production of enzymes and other substances maintenance of constant body temperature
uses of water (5)
metabolite in many metabolic reactions (condensation, hydrolysis)
solvent for metabolic reactions (aq medium)
e.g. gases, waste, enzymes, inorganic ions
able to buffer changes in temperature
supports columns of water in transport systems
surface tension when water meets air
what are inorganic ions
do not contain hydrogen or carbon
are aq in the cytoplasm of cells and bodily fluids in varying concentrations
uses of H+ ions
involved in pH which varies functions of enzymes
uses of iron ions
found in haemoglobin of red blood cells to transport oxygen
uses of sodium ions
co-transport of glucose and amino acids across plasma membrane (carries them with it)
uses of phosphate ions
components of DNA, ATP and cell membranes
structural role in DNA (part of phosphate-sugar backbone)
stores energy in ATP molecules
why is DNA replication semi conservation
allows continuity of DNA to next generation of cells
what does semi conservation of DNA mean
parent DNA molecule separates into two component strands to act as a template for the formation of a new complementary strand
forms two daughter molecules with half parent DNA half new DNA
DNA replication steps (6)
DNA helicase unwinds the double helix by breaking the hydrogen bonds between the complementary base pairs
Forms two single strands which exposed bases act as a template for free nucleotides to form new complementary base pairings by hydrogen bonds
DNA polymerase catalyses the condensation reaction to form covalent bonds between phosphate and deoxyribose of every new nucleotide, forming the phosphate-sugar backbone
Process continues for entire molecule
A winding enzyme winds the strands up to form two new helices
Each DNA molecule contains one original and one synthesised strand
