half-life problems & microscope math
What is the definition of half-life?
The time required for half of the radioactive atoms in a sample to decay.
What is a derived character?
A trait only shared by members of a specific clade.
A disease killing ⅓ of a dense population is what type of limiting factor
Density-dependent limiting factor
Who developed binomial nomenclature?
Carl Linnaeus
Humans are 99.9% genetically identical. True or false?
True
Selenium-83 has a half-life of 25 minutes. If you start with 10 mg, how much remains after 50 minutes?
2.5 mg (2 half-lives: 10 → 5 → 2.5)
What does a cladogram show?
The relative degrees of relatedness among organisms.
What is the difference between a population and a community?
A population is a group of individuals of the same species; a community is all populations in an area.
In binomial nomenclature, which part is the genus?
The first word
What is the difference between homologous and analogous structures?
Homologous – same structure, different function; Analogous – same function, different structure
The field of view at 40X magnification is 4.2 mm. What happens to the field of view as you increase magnification?
The field of view decreases as magnification increases.
What is the Red Queen Theory?
Species must constantly adapt and evolve to survive.
Name the three types of symbiosis.
Mutualism, commensalism, parasitism
What are the three criteria for an evolutionary adaptation?
Heritable, functional, increases fitness
How many haploid cells are produced from meiosis?
Four
You measure 51 red blood cells across your diameter of field (DOF). If your DOF is 0.51 mm, what is the average size of one red blood cell in micrometers?
10 μm (0.51 mm ÷ 51 = 0.01 mm = 10 μm)
Define punctuated equilibrium.
Long periods of stability interrupted by short bursts of rapid evolutionary change.
If a population grows without limiting factors, what type of growth curve does it show?
Exponential growth
Define structural, physiological, and behavioral adaptations.
Structural – body parts; Physiological – body functions; Behavioral – actions
Which domain contains eukaryotic organisms?
Eukarya
Convert 5000 g to kg.
5 kg
Crossing over in meiosis occurs during which phase?
Prophase I
Define niche.
The range of conditions and resources a species needs to survive and reproduce.
Give an example of coevolution.
A flowering plant and its pollinator evolving together.
What is the significance of the Sahelanthropus tchadensis fossil?
Supports Africa as the origin of humans; early bipedalism (~7 million years ago)