Bio 124 Chap 1 Flashcards
What is biology
Biology is the study of life both past and present and its relationship with the nonliving world
7 characteristics of life
Cellular
Growth and Development
Response to its environment
Reproduce
Regulation (homeostasis)
Energy processing (Producer like plants and algae and consumers like animals and mushrooms)
Evolutionary adaptation
Tell me the organizational levels of life
Atoms
Molecules
Macromolecules
Organelles (In the nucleus)
Cells
Tissues
Organs
Systems
Organism
What is the concept of organizational levels of life (small to large)
Emergent properties arise as you move from the smallest parts to a more complex systems biology: When small parts are grouped together, they gain more properties and move up a level!
What are the groups’ organisation of life and describe them
Population: Individuals of the same species (us)
Communities: Different populations in the same environment (us and bacteria)
Ecosystem: communities interacting with the non-living environment (us in the classroom)
Biosphere: the worldwide sum of all ecosystems
What is the lowest level of life with all 7 characteristics
Cell
What is the cell theory
Suggest that all living organism are composed of cells
What are the 4 structures of a cell
Ribosomes
Plasma membrane
Cytoplasm
DNA
What is DNA
genetic information of a cell
What is a genome
The complete set of genes or genetic material present in a cell
Are are Chromosomes
Long DNA strands
What are genes
They are segment of chromosomes that code for specific proteins and cellular actions and are the instructions of the cells (gene expression)
What are Prokaryotic cells
They are small and simple cell, lack a nucleus and other membrane-enclosed organelle
What are Eukaryotic cells
Larger and more complex cells, they have membrane-enclosed organelles including a nucleus
What is evolution
Evolution is the change in a population over time leading to unique descendants that share a common ancestor
What kind of cells are Domain bacterias and Domain archaea
Prokaryotic
What kind of cells are animals, plants, fungi, protists
Eukaryotic (more complex!)
What is natural selection
Natural selection is the process by whch a population adapts to its environment over generations
What does Darwin propose for natural selection to occur?
The population needs variable traits to produce offspring through competition for the best-suited. The environmental pressures will help select specific traits that lead to the population growing with these particular traits and adapting over time
What are phylogenetic trees?
Cladorgpahs are proposed evolutionary relationships between organisms based on available evidence. They are diagrams
How are we all connected?
All living things have 7 characteristics containing DNA and population interaction in communities and ecosystems. All living things share common ancestors and have evolved unique adaptations to their environment over time.
What is science
is a body of knowledge about the natural world acquired through observation and experimentation
What are observations?
Description, measurements, or records of objects and natural phenomena (data) which can lead to scientific questions
What are the two types of observational studies
Quantitative (numerical)
Qualitative (descriptive)
Hypothesis, what is that
Possible answer, logical and testable explanation of the observation
What are experimental studies. Explain it in full (with groups, variables etc)
They test the hypothesis to support or refute them. They must be falsifiable and produce predictions that can be tested as true or false.
Also, include a control group (IV not manipulated) and an experimental group (Independent variables manipulated)
Data is then analyse via graph
What makes a good hypothesis
logical and testable explanation
What prokaryote ad eukaryote have in common
Cell Membrane
DNA
Ribosomes
Cytoplasm
Scientific Facts and theory what is the difference
Facts are truth; direct and repeatable finding strongly supported by science
Theory are more on the larger scale they are accepted and supported and explain natural phenomena
What is the law of use and disuse, who said that
When you arent using a structure : Penguins with small wings - Larmark
Transmission of aquired characteristic - what is it and who said that
Lamark- Passing on strength for example. Not how it works
Artificial Selection
Humans have modified other species by selecting and breeding individuals with desired traits
What are the 4 major type of data that document the pattern of evolution
Direct observation of natural selection
Comparative anatomy
Fossil Record
Biogeography
Give an example of direct observation linked with evolution
Bacteria becoming resistant to antibiotic or soapberry bugs adapting their beak dependent on fruit size
Homologous structures
Anatomical ressemblances that represent variatios ion a structural theme present in a common ancestor
What is vestigial structures
Structures that were oce useful ancestrally but became less important over time
What is molecular homology
Recognize that all life uses DNA for genetic information and many share common genes
Analogous structures
Arise when population are faced with similar environmental pressures despite different ancestry
Convergent evolution
is the evolution of analogous structures
Divergent evolution
is the evolution of homologous structures
Fossils - what are they
are preserved remains of ancient organisms
Biogeographie
is the geographic distribution of species (life on land!)
Endemic Species
Are restricted to a unique geographic area
Evidence of evolution - Name 4
Natural selection in action (bacteria resistance, artificial selection, soap berry bugs)
Homologies Structures of common origins
Fossil records: See that cetaceans evolved from terrestrial mammals
Biogeography: Geographic distribution of species
Explain pre-darwin view of life
It was really influenced by religion, fixed number of species (think Noa’s boat) Fixed hierarchy with humans at the top, no change over time
Describe natural selection
It increase of decrease heritable traits - adaptations vary depending on the environmental pressures/ Population evolve overtime not the individuals
What is paleontology
Study of fossils - investigate the history of life on earth
Give the order of the Major events and their details
-4.6 bya - Earth forms
-4.4 bya Oceans form (Primodial Soup)
- 3,8 bya - first prokaryotic life
Evidence: Stromatolites (geological structures formed by colonies of organism)
-Photosynthesis begins! 3bya - Cyanobacteria emerged. Releasing o2 as a waste
-Great Oxygen Event. Major extinction of prokaryote but some group survived and adapted using cellular respiration
-First eukaryotic life
(Endosymbiont Theory: Prokaryte paralized other pro to form eurk)
-1.6 bya first multicellular life (surface to volume ratio problems) - algea most likely the first
- Cambrian Explosion: Animals begin to use minerals in sea waters to form skeletons
-500mya, animals started to colonized land (Advantage; new food source, rich nutrients, fewer predator)
Disadvantaged: Drying out, withstand gravity, reproduction method changing)
365mya: First tetrapod’s and arthropods(Plants consuming c02 began to explode in numbers
-359-299 mya - Carboniferous Period: Plants created MASSIVE amount of oxygen
(Less c02=cool down of planet) carbon sunk into swamp, soil etc.) and now we are releasing that!
299-251 mya Super continent Pangea: plate tectonics move slowly, continental drift - Endosperm emerged
252mya: Permian-Triassic Extinction event: Volcanic activity, too much C02 leading to ocean acidification and global warming
-225mya- Mammals emerged
100mya: Flowering plants and flying insects emerged
65 K-T extinction event: 75%of plant and animals die off
- Mammals rule! Adaptive radiation: rapid increase in nunmber if species from a group of organism
What is abiogenesis
Scientific theory that life arose from non-living chemicals, approx 4 bya
Anaerobic
No oxygens in atmosphere, related to prokaryotes that do not need oxygen for metabolism
What is a mass extinction
Large loses of diversity, takes a long time for it to recover. 5 mass extinction on earth
What is phylogeny
The study of evolutionary relationships between organism
Taxonomy
science of naming and grouping organism to construct an internationally shared classification system
What is a taxa
The group that organism are organised in (Kingdom, domain etc.)
What is a binomial naming system
it is scientific names made out of genus and species. Italicized or underlined if handwritten
Phylogenetic Trees and its part
Proposed evolutionary relationships
Each tre is rooted by a common ancestor for all taxa in the tree
Branching point: two lineage diverge from a recent common ancestor
Mot recent branching: Sister taxa
Homologies
Similarities due to share ancestry
What is shared derived trait
Homologous trait (divergent) that seperate them from other group as well as from their common ancestor.
Outgroup
The group that lack derived trait
What is Clade
the groups in a phylogenetic tree that shared a common ancestor
Non-heritable variation
Variation that doesn’t result from genetic differences but rather from environmental influences (Catapillar taking the colour of what they eat)
What is a species
Organisms that can interbreed and prduce viable and fertile offspring
DNA - define
a macromolecule that stores genetic info
What is a chromosone
Long strand of DNA
Genes, define
Segment of our DNA that code for certain character
Allele, define
Different form of the same gene
What do you call an organism with 2 set of chromosone
Diploid
What is the genotype
Set of allele at a particular gene
How do you call different allele at a particular gene
Heterozygous
How do you call same allele at a particular gene
Homozygous
What is a phenotype
How the gene are express (physical concequence)
What is a dominant allele
They are always express no mater the genotype
What is a recessive allele
Only expressed if dominant allele is absent
Gene Pool
sum of all allele and genes variants in a population
Allele Frequency, what is that
Relative proportion of each allele (how often you see it in a population) -When the frequency changes overtime, the population is evolving
Hardy Equilibrium - define
States that a populations allele and genotype frequencies are constant unless an evolutionary force is acting upon them
Allele frequency: p+q=1
Frequencie of genotype: p2+2pq+q2
What are the 5 force of evolution that can disrupte H-W equilibirum
Genetic Drift (Bottle neck effect severe drop of population, killing seals for example)
Founder effect: Few individuals get isolated from main pop
Non-Random mating (heritable traits, pressure from environment)
Mutations in gametes (Bacteria)
Gene flow (migration)
Natural Selection (leads to adaptation)
Inter vs intersexual selection
Intersexual = mate choice
Intersexual= compétition
Sexual dimosphism
When female looks very different then male in a population
Good gene Hypothesis
When female choose certain male traits that are related to male health
Mutation
Random errors in DNA and are the ultimate source of new allele in pop
Rarely adaptive
Mutation
Random errors in DNA and are the ultimate source of new allele in pop
Rarely adaptive
Gene flow
Migration of organism from one pop to another.
Can lead to improved or decreased population fitness
Relative fitness
Contribution an individual makes to the gene pool of the next generation.
Relative to the contribution of others
Natural selection favour certain genotype
Define the movement it can take
Directional: favour individuals at one end of the range
Disruptive: favour individuals at both end
Stabilizing: favour individuals in the middle
Balancing selection what is it and then does it occurred
When being heterozygotes has an advantage in the population
And
When there is frequency-dependant selection when the fitness of a phenotype decrease when it’s too common
Biological species concept
Describe a species as one that can create viable and fertille offspring between members
What is micro evolution and macroevolution
Consist of changes in allele frequency in a population over short time (5 forces of evolution)
Macro refers t broad patterns of evolution that lead to new species over longer time
What is speciation
Formation of 2 or more species from one ancestral population
What is needed for speciation to happen
They need to be reproductively isolated (Reproductive barrier)
Give example of pre-zygotic barriers
Pre-zygotic: Form a barrier before the egg and sperm meet
Geographic isolation
Behavioural
Temporal
Habitat
Mechanical
Gametic
Give example of post-zygotic barriers
Reduced hybrid viability: Maladaptive and lead to death (Young salamender that eventually died because of weakness)
Reduced hybrid fertility: (Mule) chromosone of two parents differ too much so the young can not reproduce
Hybrid breakdown: first generation of offspring is fertile but not the second
What is allopatric and sympatric speciation
Allopatric means other homeland. Geographic isolation is Allopatric. All the others are sympatric
Hybrid Zone
When the reproductive barrier is incomplete, two population might interbreed
