all! Flashcards
3 main differences between DNA & RNA
DNA- thymine
RNA- uracil
DNA-deoxyribose
RNA- ribose
DNA- double helix
RNA- single twisted strand
Who is Gregor Mendel?
An Austrian monk who found the basic rules of inheritance through a series of expirements
Abiotic factors
Non living physical or chemical condition in an environment
evolution
a change in gene frequency over time
change of organisms over time
4 nitrogenous bases in RNA
- uracil
- adenine
- guanine
- cytosine
Trait
A variation of a particular genetic or characteristic
Biotic factors
Any living part of an environment
adaptation
trait shaped by natural selection that increases an organism’s reproductive success in a particular environment
What are the complements of nucleic bases in RNA?
- adenine & uracil
- guanine & cytosine
Blending hypothesis
Hypothesis in 1800’s explaining how offspring inherited traits from both parents
Ecology
Scientific study of the interactions among organisms and their environments
descent with modification
identified hat species on earth today descended from ancestral species
what happens during transcription?
DNA is turned into RNA
- mRNA is created (like DNA replication, but with only one strand & with uracil instead of thymine)
Genetics
The study of heredity
What are the 5 levels of relationships among biotic and abiotic factors?
- individual organisms
- populations
- communities
- ecosystem
- biosphere
natural selection
“survival of the fittest”
process where individuals that are best fit for their environment survive to reproduce
(the change in groups of organisms through time)
Where does transcription occur?
In the nucleus
What did Mendel do for his work?
He bread pea plants and studied inheritance patterns for 7 years
population
group of individuals of the same species living in a particular area at the same time
how old is the earth
4.5 billion years old
translation
changing RNA to amino acids to make proteins
Mendel’s hypothesis
Parents pass off separate and distinct “factors” to their offspring
(Factors are known as genes now)
community
all the organisms living in an area
4 basics of natural selection
- individuals show a variety of genes
- variations pass from parent to offspring
- more offspring are produced than the environment can support
- variations that increase reproductive success will be more likely to be passed on
reactants and products of translation
reactant- mRNA
product- amino acids (proteins)
Cross fertilization
The name of the process Mendel used to cross two true breeding plants with two contrasting traits
ecosystem
community of living things plus the nonliving features of the environment that support them
darwin
collected specimens and observed finches to develop two main points- descent with modification & natural selection
where does translation occur
in ribosomes which are in the cytoplasm
Alleles
Alternate forms of genes
biosphere
all the parts of the planet that are inhabited by living things; sum of all Earth’s ecosystems
artificial selection
the selective breeding of domesticated plants and animals to produce offspring with genetic traits that human value
(Ex.dogs)
3 parts of a nucleotide in RNA
- ribose sugar
- nitrogenous base
- phosphate
Dominant allele
An allele in a heterozygous individual that appears to affect the trait
microclimate
climate in a specific area that varies from the surrounding climate region
fossil record
chronological collection of life’s remains in the rock layer (old on bottom, new on top)
3 types of RNA
- messenger RNA (mRNA)
- ribosomal RNA (rRNA)
- transfer RNA (tRNA)
Recessive allele
A allele in a heterozygous individual that appears to not affect the trait
Uneven Heating of Earth’s Surface
regions on Earth’s surface farther from the equator absorb less heat and generally experience cooler temperatures than regions closer to the equator
three parts of comparative anatomy
- homologous structures
- analogous structures
- vestigial structures
codon
in RNA, a three-base “word” that codes for one amino acid
Homozygous
An individual that has two alleles for a character that is the same
biome
major type of terrestrial ecosystem that covers a large region of Earth
homologous structures
similar structures inherited by a common ancestor
Ex. arms/ wings
what kind of RNA makes up codons
rRNA
Heterozygous
An individual that have two alleles for a character that are different
photic zones
regions of a body of water where light penetrates, enabling photosynthesis
analogous structures
structures used for the same purpose and have similar features but aren’t inherited from the same ancestor
(Ex. wings- needed to fly but evolved separately)
3 stop codons
UAA-UAG-UGA
to stop the ribosome from continuing the sequence and messing up the protein being made
Mendel’s principle of segregation
The two alleles for a character segregate (separate) during the formation of gametes (sex cells), so that each gamete carries only one allele for each character.
aphotic zone
deep areas of a body of water where light levels are too low to support photosynthesis
vestigial structures
structures that are reduced forms of functional structures in organisms
(things that don’t really work anymore)
(Ex. human appendix)
start codon
AUG
used to signal where a new amino acid sequence should start
Mendel’s Principle of Independent Assortment
during gamete formation in an F2 cross, a particular allele for one character can be paired with either allele of another character.
gametes are sorted independently
population density
number of individuals of a particular species per unit area or volume
bottleneck
when a population declines to a very low number
anticodons
a triplet of bases that is complementary to the codon in mRNA
monohybrid cross
mating of two organisms that differ in only one character
exponential growth
growth of a population that multiplies by a constant factor at constant time intervals
founders effect
small amount of organisms from a population become isolated from other populations. those traits are passed along which can lead to a change in frequency
what type of RNA makes up anticodon
tRNA
dihybrid cross
mating of two organisms that differ in two characters
carrying capacity
number of organisms in a population that an environment can maintain
genetic drift
any change in the allele frequencies in a population that is due to chance
what is the purpose of the genetic code table?
to “translate” what amino acids that codons code for
hybrid
offspring of two different true-breeding varieties
density-dependent factor
factor that limits a population more as population density increases
types of genetic drift
founders effect and bottleneck
mRNA
messenger RNA
- the primary sequence of bases after transcription
- carries the codons out of the nucleus and into the cytoplasm
Punnett square
diagram showing the probabilities of the possible outcomes of a genetic cross
density-independent factor
factor unrelated to population density that limits a population
reproductive isolation
prevents gene flow among populations
