Biology Evolution

Biology

The scientific study of living things or organisms

Evolution

A change in genetic makeup(allele frequencies) over time

In evolution….

All living organisms descended from Asingle common(called) ancestor

Evolution of species

Change in gene frequencies

Evolution only happened

Once

All living things can be traced back to a living organism…

So Living species did not evolve from other living species

Characteristics shared by all living organisms

1. composed of similar sets of chemical components(nuclei acid, proteins, carbon hydrates, etc)

2)depend on interactions from structurally complex parts

3)contains a nearly universal genetic code

4)convert molecules obtained from their environment into new biological molecules(ASSIMILATION)

5)extract energy from the environment an use if for life functions(metabolism)

6)replicate their genetic information when reproducing(mitosis/meiosis)

7)share structural similarities among a fundamental set of genes

8)evolvement through gradual changes in genetic information(changes in gene frequency)

An individual can’t evolve

But the population can

Oxygen is a

Reactive gas

Miller-Urey Experiment

Used the “primordial soup” hypothesis—the idea that complex biological molecules possibly arose from random associations of chemicals in the early environment.(This experiment simulated conditions on early Earth)

Critical Step for the evolution of life:

\-Formation of nucleic acids(that can reproduce themselves and contain info to produce proteins)

\-Biological molecules, like Fatty Acids,(formed membrane-like films in water—helping form membranes…membranes separate the cell from the surrounding environment)

Assimilation

Convert molecules obtained from their environments into new biological molecules

Metabolism

Extract energy from the environment and use it for life functions

Reductionism

An approach to reduce complex systems into simpler components

Emergent properties

Property ties that become apparent and result from various interacting components in the environment

Systems Biology

The exploration of the network of interactions the emergent properties of a system

(Ex: how does a gradual increase in atmospheric carbon dioxide alter ecosystem?)

Prokaryotes

single-celled, no organelle

Prokaryotes were confined to oceans because there was no oxygen to breathe or protect from them from the UV lights until the…

Evolution of photosynthesis(brought o2 in atmosphere and o3 in ozone layer

When did the evolution of photosynthesis occur?

2\.7 billion years ago

Photosynthesis uses sunlight by

Transforming light energy into chemical-bond energy into biological molecules

What were the earliest Cyanobacteria were similar to what?

Cyanobacteria(bacteria’s that can synesthesize)

O2 was ____ to many early prokaryotes

Poisonous

Organisms that could tolerate o2 evolved into….

Aerobic Respiration(which is more efficient than anaerobic metabolism-organisms are able to grow larger)

Aerobic Respiration

A cellular respiration that takes oxygen gas to produce energy(from food-most common metabolism used today)

Anaerobic Respiration

A cellular respiration that does not use oxygen to produce energy

Certain cells evolved into compartments called organelles. Organelles are

Membrane-enclosed organelle, where specialized functions can be performed

Nucleus

Contains genetic information

Eukaryotes

Cells that contain organelles

Endosymbiosis

Where larger cells engulf smaller ones

Mitochondria

Site of energy productions, evolved from engulfed prokaryotic organisms

Chloroplasts

Site of photosynthesis, evolved from engulfed photosynthesis prokaryotes

Cellular Specialization

Cells became specialized to perform certain functions

Cellular-Level System

Amount of free Amin acids in cell——(synthesis of protein T)——Amounf of Protein T in cell——(breakdown of protein T)——-amount of breakdown products in cell

Organization-Level System

Amount of Na+ in gut from foods—-(absorption of Na+ from gut by gut cells)——Amount of Na+ in body fluids——(excretion of Na+ by kidney cells)——Amount of Na+ leaving the body in urine

Community-Level System

Abundance of grass—(consumption of grass)—-Number of voles——(consumption of voles for food)—-Number of foxes and owls

Mutations

Error in genes..when a genome is replicated

Silent Mutation

The genetic code changes but it doesn’t impact the organism

Genome

Total set of dna in an organism(combined chromosomes are genomes)

Phylogenetic Trees

They document and diagrams evolutionary relationships

Kingdom

(Taxon-kinda outdated)The highest classification into which living organisms are grouped in Linnean taxonomy, ranking above a phylum(ex: Animale, Plantae)

Phylum

(Taxon) a major group of animals or in some classifications(ex: Chorodata, Arthropoda)

Class

(Taxon) A taxonomic rank below the phylum (or division) and above order(ex: Mammalia, Inseda)

Order

(Taxon) A taxonomic rank above family(ex: Primate, Carnivora, Coleoptera)

Family

(Taxon) a taxominc rank above Genus and Species. ALWAYS ENDS IN -IDAE

Genus

A genus is a (Taxon) taxonomic classification that includes closely related species(ex: homo, panthera)

Species

a group of organisms that can reproduce with one another in nature and produce fertile offspring(ex: sapien, tigris)

Example of Kingdom

Animalia, Plantae

Example of Phylum

Chordata, Arthropoda

Example of Order

Primate, Carnivora, Coleoptera

Example of Family

Hominidae, Felidae, Lampyridae

Example of Genus

Homo, Panthera

Example of Species

Sapien, Tigris

Domain

the highest taxonomic rank in the hierarchical biological classification system, above the kingdom level

3 Domains of Life

Bacteria(prokaryote), Arcchaea(Prokaryotes), Eukarya(Eurkaryotes)

Model Organisms

 An organism suitable for studying a specific trait, disease, or phenomenon, due to its short generation time, characterized genome, or similarity to human

Example of Model Organism

Mouse(Mus), Fruit Fly(Drosophila), Nematode(Microscopic worm—C. Elegans)

Second Law of Thermodynamics

Left to themselves, organized entities ten to become more random, leading to disorder(ENTROPHY)

Homeostasis

Energy used to stabilizes the body for the tendency for their molecules, structures, and systems to lose organization

Binomial

2 word names that includes the genus and Species

Population

Members of the same species in an area, HAS TO BE ABLE TO INTERBREED

Community

Different species/populations under a single area

Ecosystem

A community and the physical landscape(non-living things)

Biosphere

Anywhere on the planet that can support life

Open System

Where energy can be transferred between the system and its surroundings

Positive Feedback

Occurs when a product of the system speeds up an earlier process(more rare than Negative Feedback)

Negative Feedback

Occurs when a product of the system slows down an earlier process(common) and stabilizes systems

Example of Positive Feedback

Pregnancy

Example of Negative Feedback

Fever and sweating

Negative Feedback is common found in

Regulatory Systems

Genome

The sum total of all the information encoded by an organism’s genes

Nucleic Acids

Consists of repeating subunits called nucleotides

Gene

Specific segment of DNA that contains information coding for proteins

Polymer

Long molecule made up of repeated monomers

Monomers

Made up of amino acids

Translation

the process through which information encoded in messenger RNA (mRNA) directs the addition of amino acids during protein synthesis

Transcription

the process of making an RNA copy of a gene’s DNA sequence. This copy, called messenger RNA (mRNA), carries the gene’s protein information encoded in DNA

What do proteins do?

Govern chemical reactions in cells and help form an organism’s structure

Differentiation

All cells in multicellular organisms contain the same genome, but different cells have functions—b/c certain genes aren’t expressed in the cell

Differentiation Example

A liver cell has the same DNA as a bone cell in one organism but the bone function isn’t expressed in the genome of the liver cell

Mutation

ERROR in DNA replication(or any change in nucleotide sequences)

How can mutations occur?

Chemicals and radiation—which is a MUTATGEN

Types of Mutations

Deleterious, Silent, and Beneficial

What properties drive evolution?

Mutation, selection, and genetic drift

Theory

A body of scientific work which is rigously tested and well established(of facts) to make predictions

How can evolution be tested?

Changes in genetic composition in a population, laboratory experiments, and fossil record(population changes over long time frames)

Microevolution

Changes over genetic makeup(allele frequency) over a short time period. It can be tested(in a lab)

Macroevolution

Changed over genetic makeup(allele frequency) over a larger period of time, which can’t be tested

Technology

Application of scientific knowledge

Scientific Method(ology)

1) Observation

2) Question

3) Hypothesis(testable)

4)Predictions(of how the experiment will go)

5) Experiment

Hypothesis

A prediction based on observation—HAS TO BE TESTABLE

Controlled experiments

Manipulates a single variable

Variable

That is being manipulated or changes in response to the ind. variable

2 types of variables

Dependent and Independent variable

Controlled Variable

In a controlled experiment, the controlled variable would be the same(in terms)

Null Hypothesis(H_o)

Claims there is no statistical difference exists between 2 quantities and events are due to random chance

Religious or Spiritual explanations are

Outside of there realm of science and can’t be tested

Mendel

Pea Plants, cross-pollination, 2 alleles: dominant and recessive,

Nucleotides

The monomer unit of nucleic acid such as DNA and RNA

The product of genes is/are

Proteins

Evolutionary Theory

Understanding and application of the processes of evolutionary change to biological problems