DNA
information
Codon
3 nucleotides in a sequence for an amino aid
Anticodon
set of three nucleotides that compliment the mRNA
rRNA
ribosomal RNA, part of ribosome
mRNA
messenger RNA, is the info transcribed from the DNA
tRNA
transfer RNA, brings amino acids to ribosomes to make protein
Carcinogens
radiation, smoking, the sun
What is Replication
process in which DNA is copied
First step of replication
DNA is unwound from double helix, and unzipped by helicase. This step breaks the hydrogen bonds.
Second step of DNA replication
Free nucleotides are hydrogen bonded to their complimentary base pair
DNA polymerase
enzyme that bonds nucleotides to the strand
only work s on 5’ to 3’
Leading stand
flows smoothly
lagging strand
works in pieces
Ligase
glue for lagging strand
Third step of DNA replication
results in 2 identical strands. 1 new strand and 1 original strand.
Where does DNA replication occur in Prokaryotes (bacteria)?
cytoplasm
Where does DNA Replication occur in Eukaryotes (plants and animals)?
Nucleus
Transcrption
The cell makes a RNA copy of a piece of DNA
Where does Transcription occur?
nucleus
What replaces Thymine in RNA?
Uracil
What is RNA?
chain of nucleotides
What is the first step of transcription?
Initiation
What happens in Intiation?
RNA polymerase unwinds the DNA, bonds nucleotides
What is the second step of transcprtion?
Elongation
What happens in Elongation?
complementary nucleotides are added to 3’ and mRNA
What is the third step of transcription?
Termination
What happens in Termination?
mRNA detaches from the DNA, and exits through nuclear pore.
Translation
the process that converts mRNA to a polypeptide
Where does translation occur?
cytoplasm
What occurs in the first step of translation?
codon attaches to the complimentary mRNA
What occurs during the second step of translation?
Ribosome forms peptide bond amino acids
What occurs in the third step of translation?
Ribosomes pull the mRNA, so the tRNA exits. Now, a new mRNA is open ans new tRNA will arrive.
What does RNA have instead of Thymine?
Uracil
Can the DNA or the RNA leave the nucleus?
RNA
DNA is involved in?
transciption
RNA is involved in?
Transcription and Translation
What is the function of mRNA?
carry genetic info needed to make proteins
What is the function of rRNA?
to help translate the information mRNA into protein.
What is the function of the tRNA?
bring amino acids to the ribosomes to make proteins
What is insertion?
Frameshift mutation
Why is insertion and deletion bad?
Changes that protein and all others after that
What is deletion?
Deletes something where it was supposed to be, causes a frameshift
What is a nonsense substitution?
When protein ends too early
Why is a nonsense substitution harmful?
It may not have all the proteins it needs
Homozygous
Pure breed
Heterozygous
Hybrid
Gregor Mendel
Did an experiment with pea plants and discovered some traits were dominant
Allele
piece of chromosome that codes for a certain system
Genotype
genes
Phenotype
physical appearance
Sex-linked inheritance
characteristics influenced by genes on sex chromosomes
Why is there a reduction of chromosomes in Meiosis?
To ensure during the union of two gametes in fertilization, there is not double the needed amount of chromosomes
What does the reduction of chromosomes make possible?
Diplody
Diplod
having two complete sets of chromosomes in an organism with each parent contributing a chromosome to each pair
Zygote
a cell formed by the union of two sex cells
Prophase 1
Spindle fibers form and nucleus breaks down
What happens to chromosomes in prophase 1?
Homologous chromosomes line up in tetrads, and chromosomes cross over
Homologous chromosomes
2 chromosomes in a pair- normally one inherited from the mother and one from the father
Metaphase 1
pairs of homologous chromosomes line up
Anaphase 1
pulled to poles by spindles
Telophase 1
Cytoplasm divides 2 diploid cells
Prophase 2
new spindle fibers form and nucleus fades
Metaphase 2
individual chromosomes line up in the middle
Anapahse 2
centromeres divide to poles
Telophase 2
4 haploid cells form
How does meiosis provide genetic variation?
Creates new combinations of genetic material in each of the 4 daughter cells
Are gametes haploids or diploids?
haploids
When are genes more likely to be linked?
ones that are closer to each other on chromosomes
Incomplete dominance
Neither genes are dominant, appears as a blend
Co dominance
Both genes are dominant, and both appear
What are the possible genotypes fro someone who is type A blood?
AA or AO
Which chromosome more commonly has the genetic disorders?
The X chromosome
Why does the X chromosome more commonly have the genetic disorders?
both men and women have x chromosomes
Relative dating
looking at where it is in the rock layers to determine age
Natural selection
the fittest survive and reproduce, those who are not fit die off
Evolution
change over time
Fitness
organisms will survive and reproduce more often
Adapation
any trait that increases fitness
Niche
an organism’s role in an ecosystem
Artificial selection
humans change species by breeding for certain traits
Founder effect
new colony is started by only a few members
Bottleneck effect
population declines to a low number, but then rebounds
Homologous structures
same structures but different functions
Analogous structures
same functions but different structures
Vestigial structures
structure that has lost most or all function, but is still present
Taxonomy
naming and classifying of animals
Embryology
study that compares organisms’ fetus in early stages
Divergent evolution
1 species gives rise to many species
Convergent evolution
2 unrelated species develop similar traits due to similar enviorments
Co-evolution
species evolve as result of a close relationship
What is some evidences of evolution?
Homologous structures
Vestigial structures
Embryology
What is a key difference in artificial and natural selection?
Artificial selection does not always breed for the most beneficial traits
Reproductive isolation
a species cannot breed
How could a species become reproductively isolated?
Temporal isolation
geographic barrier
behavioral
Polyploidy
extra chromosome, makes it so you can not have offspring
Abiotic
non living
Biotic
living
Symbiosis
when organisms interact with one another
Parasitism
one organism is benefited while the other is harmed
Commenalism
one organism is benefited while the other is not affected