Bio 181 Unit 1 Flashcards
(62 cards)
1
Q
Biology
A
Study of life
2
Q
Seven characteristics of life
A
- growth, development, reproduction
- Energy utilization
- Cells
- Homeostasis
- Ordered complexity
- Evolutionary adaptation
- Sensitivity
3
Q
Levels of organization
A
- atoms
- molecules
- macromolecules
- organelles
- cells
- tissues
- organs and organ systems
- organisms
- populations
- communities
- ecosystems
- biosphere
4
Q
Each level of organization has emergent properties
A
- result from interaction of components
- cannot be deduced by looking at parts themselves
5
Q
The process of inductive reasoning involves:
A
- the use of general principles to predict specific results
- the use of specific observations to develop general principles
- the use of general principles to support a hypothesis
- the generation of specific predictions based on a belief system
6
Q
Inductive Reasoning
A
uses related observations to arrive at a general conclusion (main way to do scientific inquiry in biology)
7
Q
Deductive Reasoning
A
uses a general principle or law to forecast specific results
8
Q
Scientific Method
A
- pose questions and seek science based response
- inductive methods for scientific inquiry
researchers from almost all fields of study can apply it as a logical, rational problem-solving method
9
Q
Steps of Scientific Method
A
- Observation: use your senses
- Come up with question(s)
- Create hypothesis
- Make prediction
- Conduct experiment/study
- results (is hypothesis supported or not? if not go back to the drawing board. Either way report results)
10
Q
Hypothesis
A
- a proposed explanation for a natural phenomenon or observation
- possible explanation for observation
- must be tested in many different ways
- allows for predictions to be made
- iterative (repeating)
11
Q
Experimental Variables
A
- test hypothesis
- tests one variable (thing) at a time
- consists of: test experiment and control experiment
12
Q
Three Main Variables
A
- Independent = condition
- Dependent = what we’re going to measure
- Control = variables that are not changed
13
Q
Qualitative Data
A
- descriptions
- data observed, but cannot be measured
- Ex: colors, smells, beauty
14
Q
Quantitative Data
A
- numbers
- measured
Ex: length, time, height
15
Q
Misconceptions of Evolution
A
- humans descended from monkeys (rather humans and monkeys have a common ancestor)
- evolution is just a theory
- individuals evolve
- evolution explains the origins of life
- organisms evolved on purpose
16
Q
Evolution
A
change over time in a population of a species
17
Q
Macroevolution
A
rise of a new species (from old) and higher taxonomic groups with widely divergent characters (speciation)
18
Q
Microevolution
A
- change within a population
- changes in heritable characteristics/allele/gene frequency over time
19
Q
Mutation
A
- changes the genetic structure of population
- a rare change in DNA
- ultimate source of new alleles, or new genetic variation in any population
- point mutation: most common mutation of genes and DNA
- not all mutations are bad, most are harmful or neutral
20
Q
Natural Selection
A
- changes the genetic structure of a population
- environment plays a key role
- genetic variation = raw material for selection
- NS operates on the individual
- evolution acts on the population
21
Q
Gene Flow (migration)
A
- changes the genetic structure of a population
- the flow of alleles in and out of a population due to the migration of individuals or gametes
- can occur when an individual travels from one geographic location to another
22
Q
Genetic Drift (random)
A
- changes the genetic structure of a population
- allele frequencies within a population change randomly
- no advantage to the population over existing allele frequencies
- tends to reduce genetic variation in small populations
23
Q
Population Bottleneck
A
a chance event or catastrophe can reduce the genetic variability within a population
- genetic drift
24
Q
Founder Effect
A
an event that initiates an allele frequency change in an isolated part of the population, which is not typical of the original population
- genetic makeup not representative of larger population left behind
- genetic drift
25
Recombination
- changes the genetic structure of a population
- AKA non-random mating: the probability that 2 individuals in a population will mate is not the same for all possible pairs of individuals
26
Variation
individuals within a population have different characteristics/traits (or phenotypes)
- condition of natural selection
27
Inheritance
offspring inherit traits from their parents (transmission to next generation)
- condition of natural selection
28
Competition
off spring with traits better matched to the environment survive and reproduce more efficiently than others
- condition of natural selection
- the environment plays a key role
- genetic variation = raw material for natural selection
- natural selection operates on the individual
- evolution acts on the population
29
Evidence of Microevolution
- artificial selection: agriculture (corn has changed in shape, size, color)
- evolutionary transitions
30
Stabilizing Selection
individuals with average phenotypes are favored (ex: human birth weight)
31
Directional Selection
individuals that vary in one direction from the mean are favored (ex: resistance to tetrodotoxin in garter snakes)
32
Disruptive Selection
individuals at both extremes are favored: results in bimodal distribution (ex: black-bellied seed crackers of Cameroon)
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Sexual Selection
favors traits that enhance reproductive success
- intrasexual: improves ability to compete for mates (horns, antlers)
- intersexual: improves ability to attract the opposite sex (bright colors, long tails)
34
Understanding Evolution
- Charles Darwin
- 1831: received BA in Theology
- 1831-1836: traveled around the world on HMS Beagle; collected thousands of plants and animals (important: Galapagos Islands)
- 1844: essay on origin of species, didn't publish
- 1858: Alfred Russel Wallace (ARW) sent his theory of evolution to Darwin
- 1859: The Origin Of Species by Means of Natural Selection (by Darwin) was published
35
Sickle Cell Anemia
- reduced ability to deliver oxygen
- the cell can't pass through the capillaries → painful clots
- decreased risk of malaria
- sickle shaped cells don't live as long which makes it more difficult for the parasite that causes malaria to reproduce
36
Evidence of Natural Selection (microevolution)
Evolutionary transitions
- fossil evidence
ex: oldest known bird is Archaeopteryx. Intermediate between dinosaur and bird. Some ancestral traits and present day traits.
37
Biogeography
- founder: Alfred Russel Wallace
- he found that as species colonized new habits, and old ranges were divided by barriers, they took on distributions they have today
- as continents collided, species mingled. When contents separated, new species went with them
38
Convergent Evolution
- similarities due to similar selection pressure
- similar phenotypes evolve in distantly related species due to the same evolutionary pressures
39
Analogous Characters
- evidence of macroevolution
- similar due to functional or ecological constraints/pressures
- similar in appearance due to evolutionary convergence
40
Homologous Characters
- evidence of macroevolution
- similar due to evolutionary origin (same ancestral source)
41
Biological Species Concept (BSC)
- produce viable offspring
- criticisms: Difficult to apply concept to populations that are geographically separated. Many species hybridize in captivity. Many organisms are asexual.
42
Ecological Species Concept
The concept of a set of organisms exploiting or adapted to a single niche
43
Phylogenetic Species Concept
The concept of a species as an irreducible group whose members are descended from a common ancestor and who all possess a combination of certain defining, or derived, traits
44
Evolutionary Species Concept
The concept of a lineage (an ancestral-descendant sequence of populations) evolving from others and with its own unitary evolutionary roles and tendencies
45
Subspecies
- a biological classification that ranks below species
- designates a population of a particular geographic region genetically distinguishable from other such populations of the same species
- capable of interbreeding where range overlaps
46
Speciation
Formation of two species from one original species
47
Anagenesis
When population of entire species changes on genetic level without a split.
- ancestral population goes extinct
- AKA phyletic evolution, evolution, gradualism
48
Cladogenesis
Species splits into two genetically-distinct populations adapted to different ecosystems and/or survival strategies.
- both species may survive
49
Allopatric Speciation
Involves geographic isolation.
- each variety in its own range
- become species due to drift and local adaptation
50
Sympatric Speciation
Occurs in the same geographical area.
- many varieties in one range
- become species through adaptation to different aspects of the range
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Gradualism
- changes in species is slow and gradual, occurring in small periodic changes in gene pool
- standard view for a long time
52
Punctuated Equilibrium
- occurs in spurts of relatively rapid change with long periods of non-change
- stabilizing and oscillating selection is responsible for stasis
53
Adaptive Radiation
A clade (group of related species) that has evolved into numerous, diverse forms
54
Reproductive Isolation - Prezygotic
The separation of different species to keep them from creating offspring by preventing the gametes from forming a zygote.
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Prezygotic - Temporal Isolation
Species have different breeding schedules.
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Prezygotic - Habitat Isolation
Members of species move or are otherwise separated.
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Prezygotic - Behavioral Isolation
Certain actions or behaviors (or the lack of them) impacts reproductions.
58
Prezygotic - Mechanical Isolation
Their reproductive structures simply do not fit together.
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Prezygotic - Gametic Barrier
Differences in their gamete cells (eggs and sperm) prevent fertilization.
60
Reproductive Isolation - Postzygotic
A reproductive barrier that occurs after fertilization and prevents the production of viable offspring.
61
Postzygotic - Hybrid Inviability
An embryo is produced, but cannot survive development.
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Postzygotic - Hybrid Sterility
Different species can produce a viable offspring, but that offspring cannot reproduce.
