Bio 7-9 excel export csv Flashcards
3 stages of DNA replication
- enzymes (helicases) bind to the DNA molecule 2. the helicases separate the two strands of DNA, and DNA polymerase helps attach to new, incoming DNA nucleotides one at a time onto the surface of the exposed strands. nucleotides enter their position according to base-pairing 3. result = two identical double-stranded DNA molecules
accessory pigments
pigments other than the green chlorophylls that are commonly found in plants. ex: carotenoids
all organisms use nucleic acids as their genetic material to:
- store information that determines the characteristics of cells and organisms 2. direct the synthesis of proteins essential to the operation of the cell or organism 3. chemically change (mutate) genetic characteristics that are transmitted to future generations 4. replicate prior to reproduction by directing the manufacture of copies of itself
carbon dioxide undergoes carbon fixation, which occurs in where?
the calvin cycle
discrete packags of light energy is called:
photons
electrons released from photosystem ____ end up in the chlorophyll molecules of photosystem ____
2,1
genetic information controls many cellular processes including:
- digestion and metabolism of nutrients / elimination of harmful wastes 2. repair/assembly of cell parts 3. reproduction of offspring 4. the ability to control when and how to react to changes in the environment 5. coordination and regulation of all life’s essential functions
grana
consist of stacks of individual membranous sacs, called thylakoids, that contain chloraphyll
photosystems
arranged clusters of chlorophylls and other pigments involved in trapping sunlight energy and storing it
stroma
the spaces between the membranes
thylakoids
sacs containing chlorophylls, accessory pigments, electron-transport molecules, and enzymes
what are the base pairs for DNA
A (adenine) pairs with T( thymine), G (guanine) pairs with C (cytosine)
what are the three distinct events in the photosynthetic pathway
- light-capturing events 2. light-dependent reactions 3. light-independent reactions
what are the two distinct regions of chloroplasts?
grana and stroma
what happens in the light-capturing events of photosynthesis?
light energy is captured by chlorophyll and other pigments, resulting in excited electrons
what happens in light-dependent reactions of photosynthesis
the energy of the excited electrons is used to disassociate water molecules into hydrogen and oxygen, and the oxygen is released. ATP is produced and NADP+ picks up hydrogen released from water to form NADPH.
what happens in light-independent reactions
ATP and NADPH are used to help combine CO2 w/ a 5-carbon molecule, so that organic molecules, such as glucose, are produced.
what is the equation that summarizes the chemical rxns that photosynthetic organisms use to make ATP and organic molecules
light energy + carbon dioxide + water —> glucose + oxygen
what kinds of prokaryotic organisms are capable of manufacturing organic compounds using light energy
cyanobacteria
which kinds of organisms use respiration to generate ATP?
plants, animals and algae
how do cells use DNA and RNA differently?
DNA is found in the cell’s nucleus and is the original source for information to make proteins. RNA is made in the nucleus and then moves into the cytoplasm of the cell where it becomes directly involved in the process of protein assembly.
how are proteins synthesized?
in two steps: transcription and translation
step one: transcription
Making RNA. the process of using DNA as a template to synthesize RNA. In eukaryotic cells, occurs in nucleus. Messenger RNA carries the blueprint for making the necessary protein. Transfer RNA and ribosomal RNA are used to read the mRNA and bring the necessary amino acids together for assembly into a protein.
step two: translation
Making Protein. the process of using the information in RNA to direct protein synthesis by attaching amino acids to one another. In eukaryotic cells, occurs in cytoplasm. mRNA is read through codons (sets of three nucleotides that cosed for the placement of a specific amino acid). 3 steps of translation: initiation, elongation & termination
epigenetics
changes in gene expression caused by factors other than alterations in a cell’s DNA. do not alter the nucleotide sequence.
mutation
any change in the DNA sequence of an organism
point mutation
a change in a single mucleotide of the DNA sequence
types of point mutations
missense mutation: causes the wrong amino acid to be used in making a protein. silent mutation:a nucleotide change that results in either the placement of the same amino acid or a different amino acid but does not cause a change in the function of the completed protein. nonsense mutation: causes a ribosome to stop protein synthesis by introducing a stop codon too early.
chromosomal aberration
a major change in DNA that can be observed at the level of the chromosome
4 types of aberrations:
inversion: occurs when a chromosome is broken and a piece becomes reattached to its original chromosome, but in flipped orientation. translocation: a broke segment of DNA becomes integrated into a different chromosome. duplications: a portion of a chromosome is replicated and attached to the original section in the sequence. deletion: result when a broken piece becomes lost or destroyed before it can be reattached