branch of biology that deals with the interactions among organisms and their environments
What aspect of Lamarck's ideas about evolution was incorrect?
He believed that acquired characteristics could be passed on from parent to offspring.
What is the meaning of the term "diploid"?
A cell with two sets of chromosomes--one from each parent.
What is incomplete dominance?
When one allele is not completely dominant over another, so that the resulting phenotype is a blend.
What happens during metaphase of mitosis?
The chromosomes line up in the middle of the cell.
Describe nondisjunction and when it occurs.
Chromosomes fail to separate during anaphase 1 or 2 of meiosis.
What is the result of mitosis?
Two genetically identical cells result from mitosis.
What is the probability that 2 heterozygous parents will have a homozygous offspring?
50%
Describe the greenhouse effect.
This is when gases in the atmosphere build up and act as a blanket to the earth, preventing heat from escaping into outer space.
The two part scientific name for an organism is based on which taxa for classification?
Genus species
Why are fossil fuels nonrenewable?
They form over millions of years.
Give an example of a heterozygous genotype.
Xx
What is a well supported, testable explanation of phenomena that have occurred in the natural world?
Theory
What does the term genotype mean?
The genetic makeup of an organism, represented by letters.
Compared to complete dominance, how do co-dominant alleles affect the phenotypes of organisms?
They increase the number of different phenotypes that are possible.
How is meiosis 1 different from meiosis 2?
Interphase occurs before meiosis 1, but does not occur before meiosis 2.
How many and what type of cells result from meiosis?
4 genetcially different cells
What happens during each of the following phases of interphase: G1, S, and G2?
G1- cell growth
S- DNA synthesis
G2- prepare for mitosis
Why is do cells divide before they become too large?
Large cells place more demands on DNA, the cell has trouble moving enough material in and out of the cell membrane
When does crossing over occur?
Prophase 1 of Meiosis
What is a vestigial structure?
A structure or body part that once had a purpose, but is not currently used by a species
Explain what a cladogram is and how organisms are organized onto it.
A cladogram is a diagram that shows the evolutionary relationships among organisms; they're plotted as branches based on derived characteristics that are shared
How many chromosomes do normal human somatic cells have?
46
List the three domains in our current classification system.
Eukarya, Archea, Bacteria
Give an example of a homogenous genotype.
XX or xx
How many sets of chromosomes does a gamete have?
one set (23 total chromosomes)
Define behavior.
The way an organism reacts to stimuli in its environment.
List three things required for evolution to occur.
Variation in the population, Genetic mutations/adaptations, Competition in the population
If we start with 100 atoms of a radioactive substance, how much will remain after 3 half lives?