Biology Semester Review (Part 1)
Know the major characteristics of the eras and periods of the geological time scale
Paleozoic Era: 544 mil years ago, diversity of marine life -cambrian period: first known representatives of most know animal phyla -ordivician and silurian periods: first land animals, vertebrates, and plants -devonian period: age of fishes -carboniferous and permian periods: reptitles and winged insects evolved; mass extinction at the end if the permian period Mesozoic era: 245 mil years ago, age of reptiles, dinasours becane dominant, flowering plants -triassic period: fish, insects, reptiles, cone bearing plants -jurassic period: dinasours became the dominant land animals, one of first birds appeared-Arxhaeopteryx -cretaceous period: dominant animals- birds, turtles, crocadiles, fishe, marine invertebrates; new forms of life-leady trees, shrubs, and small flowering plants Cenozoic era: age of mammals -tertiary period: marine mammals like whales and dolphins evolved; grasses evolved -quaternary period: climate cooled causing ice ages; marine life forms evolved
Virus
Particle of nucleic acid, protein, and in some cases, lipids
What types of evidence did Darwin use in his time to support his theory of change over time?
Patterns of diversity, the relationship between living organisms and fossils, and his comparison of the characteriatics of animals and plants in the galapogos islands
What are photoautotrophs and chemoautotrophs?
Photoautotrophs: use light energy to convert carbon dioxide and water to carbon compounds and oxygen Chemoautotrophs: perform chemosynthesis; make organic molecules from carbon dioxide but do not require a source of light energy
Which kingdom contains eukaryotic autotrophs with fell walls composed of cellulose?
Plantae
Coevolution
Process by which organisms that are closely connected evolve together by ecological interactions.
Convergent Evolution
Process by which unrelated organisms come to resemble one another.
How do prokaryotes and eukaryotes differ?
Prokaryotes: no nucleus Eukaryotes: have a nucleus
Jean-Baptiste Lamarck
Proposed that by selective use or disuse of organs, organisms acquired or lost certain traits during their lifetime. These traits could then be passed on to their offspring, leading to a change in species
Which kingdom is the most diverse, and contains mostly unicellular organisms that live in freshwater ponds?
Protista
Genetic Drift
Random change in allele frequency
Thomas Malthus
Reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone. Also determined that factors limiting population growth include war, famine, and disease
Crossing-over
Results in the exchange of new alleles between homologous chromosomes and produces new combinations of alleles
BACTERIA & VIRUSES
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BIOTECHNOLOGY
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CLASSIFICATION
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Contrast the chromosome number of body cells and gametes
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EVOLUTION
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GENETICS
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How do scientists make changes to DNA?
1. DNA Extraction 2. Cutting DNA 3. Separating DNA
What happens during transformation?
A cell takes in DNA from outside the cell which becomes a component of the cell's DNA
What is the structure of a virus?
A core of DNA or RNA surrounded by a protein coat
How are transgenic organisms made?
A gene from one organism can be inserted into the cells from another organism, which can then be used to grow new organisms
Clone
A member of a population of genetically identical cells produced from a single cell
Molecular clock
A model that uses DNA comparisons to estimate the length of time that 2 species have been evolving independently
Karyotype
A picture of chromosomes (arranged by photographing cells in mitosis, when the chromosomes are fully condensed and easy to see, and grouping them together in pairs)
Vaccine
A preparation of weakened or killed pathogens; prompts the body to produce immunity to a disease
Plasmid
A small, circular DNA molecule found naturally in some bacteria and useful for DNA transfer
Endospore
A type of spore produced in harsh conditions when a bacterium produces a thick internal wall that encloses DNA and a portion of its cytoplasm
Retrovirus
A virus containing RNA as its genetic information
Lytic Infection
A virus enters a cell, makes copies of itself, and causes the cell to burst
Lysogenic Infection
A virus integrates its DNA into the DNA of the host cell, and the viral genetic information replicates along with the host cell's DNA
Viral Disease Examples
AIDS, influenza, chickenpox
Fitness
Ability of an organism to survive and reproduce in its environment
Provirus
Aka prophage: viral DNA that is embedded in the host's DNA
What does the Hardy-Weinberg Principle state?
Alleles in a population will remain constant unless one or more factors cause those frequencies to change.
Gene Therapy
An absent or faulty gene is replaced with a normal, working gene
Adaptation
Any inherited characteristic that increases chances for survival Types: Anatomical - structural characteristics Ex: porcupine's quills Physiological - an organism's functions Ex: photosynthesis in plants Behavioral - complex features, the way in which animals behave Ex: animals living and hunting in groups
Which domain contains bacteria that live in extreme environments?
Archaea
How do natural selection and artificial selection differ?
Artificial selection: nature provides the variation, and humans select those variations that they find useful Natural selection: "survival of the fittest;" results in changes in the inherited characteristics of a population, increasing a species' fitness in its environment
How do autotrophs and heterotrophs differ?
Autotrophs-make their own food Heterotrophs-obtain their food/energy from other organisms
Be able to name bacteria by shape and arrangement
Bacilli: rod Cocci: spherical Spirilla: Spiral and corkscrew Diplo: pairs Strepto: chains Staphylo: groups
Understand the processes by which bacteria reproduce asexually and sexually
Binary fission: when a bacteria has grown so that it has nearly doubled in size, it replicates its DNA and divides in half, producing two identical daughter cells Conjugation: a hollow bridge forms between two bacterial cells, and genes can move from one cell to the other; allows bacteria to exchange genetic information
How do antibiotics work?
Block the growth and reproduction of bacteria
Codominance
Both alleles contribute to the phenotype Ex: In some chickens, the allele for black feathers is codominant with the allele for white feathers, forming speckled white and black feathers in heterozygous chickens
Radioactive Dating
Scientists calculate the age of a sample based on the amount of remaining radioactive isotopes it contains.
How are bacteria identified?
Shape, chemical nature of their cell walls, the way they move, and the way they obtain energy
Pedigree
Shows the relationships within a family
Viroids
Single-stranded RNA molecules that have no surrounding capsids
Genetic Equilibrium
Situation in which allele frequencies remain constant (population will not evolve)
Principle of Dominance
Some alleles are dominant and others are recessive
Charles Darwin
Studied patterns of diversity, living organisms and fossils, and the varied characteristics of the animals and plants in the Galapagos Islands to propose the theory of evolution: Living things have been evolving on Earth for millions of years and probably developed from one common ancestor.
Bacterial Disease Examples
Tetanus, strep throat, tooth decay
Relative Dating
The age of a fossil is determined by comparing its placement with that of fossils in other layers of rock.
Speciation
The formation of new species
What happens during the process of meiosis?
The number of chromosomes per cell is cut in half through the separation of homologous chromosomes in a diploid cell
Adaptive Radiation
The process by which a single species or small group of species evolve into several different forms that live in different ways.
Fossil (& how do they form)
The remains or evidence of organisms that lived in the past. Fossils form when an animal dies and its remains become buried under sediment and preserved
How is sex determined?
The sex chromosome, or last chromosome, determines an individual's sex XX=female XY=male
What are bacteria
The smallest and most common microorganisms known as "prokaryotes"
Evolutionary classification
The strategy of grouping organisms together based on their evolutionary history
Phylogeny
The study of evolutionary relationships among organisms. A cladogram shows evolutionary relationships amoung a group of organisms
Biodiversity
The variety of species in a community
Prions
Tiny particles consisting of only protein
What is the goal of the Human Genome project?
To analyze the human genome sequence
What is the function of gel electrophoresis?
To separate and analyze DNA fragments
Why do biologists classify organisms?
To study the diversity of life
Taxonomy
Branch of biology that names and classifies organisms into groups according to etablished criteria
Mutation
Change in a DNA sequence that affects genetic information
Gene Pool
Consists of all genes, including all of the different alleles, that are present in a population
What is the role of bacteria in the environment?
Decomposers, nitrogen fixers (converting nitrogen gas into a form that plants can use), removing wastes from water and the environment
Carolus Linnaeus
Developed the current universally accepted naming system
Punnett square
Diagram that determines the gene combinations that result from a genetic cross
Variation
Differences between organisms/species as a result of genetic difference or environmental factors
Names and characteristics of the domains and kingdoms in the current system of classification
Domain Bacteria: unicellular, prokaryotic, thick, rigid cell walls made of peptidoglycan that surround a cell membrane -Kingdom Eubacteria " " Domain Archaea: unicellular, prokaryotic, live in extreme environments, cell walls lack peptidoglycan -Kingdom Archaea: " " Domain Eukarya: consists of all organisms that have a nucleus -Kingdom Protista: cannot be classified as plants, animals, or fungi, greatest variety of members -Kingdom Fungi: heterotrophs, most feed on dead or decaying organic matter, secrete digestive enzymes into their food source -Kingdom Plantae: multicellular, photosynthetic autotrophs (carry out photosynthesis), cell walls containing cellulose -Kingdom Animalia: multicellular, heterotrophic, no cell walls, lots of diversity
Which kingdom contains prokaryotes with cell walls made of peptidoglycan?
Eubacteria
Compare and contrast evolution, microevolution and macroevolution
Evolution: change over time Microevolution: small-scale evolutionary change taking place over short periods of time Macroevolution: large-scale evolutionary changes taking place over long periods of time
What types of evidence do scientists use today to study evolutionary histories of organisms?
Fossil record, geographical distribution of living species, homologous structures of living organisms, and similarities in early development, or embryology
Index Fossil
Fossil used to compare the relative age of fossils. To be used as an index fossil, a species must be easily recognized, have existed for a short period, and have a wide geographical range
Which kingdom contains eukaryotes with cell walls composed of chitin?
Fungi
Principle of Independent Assortment
Genes for different traits can segregate independently during the formation of gametes
Binomial Nomenclature
Two word naming system using the genus and species of an organism Ex: Canis (genus) familaris (species) **note: both names must be italisized, the first word must be capitalized, the second word is not
Human Blood Type Alleles
Type A - I^A,I^A or I^A,i Type B - I^B,I^B or I^B,i Type AB - I^A,I^B Type O - ii
Bacteriophage
Virus that infects bacteria
What is the scientific contribution of Ian Wilmut?
He cloned a sheep (Dolly!)
What is the scientific contribution of Gregor Mendel?
He experimented with pea plants and made two conclusions: 1) Biological inheritance is determined by factors that are passed from 1 generation to another 2) Principle of dominance
Charles Lyell & James Hutton
Helped scientists recognize that Earth is many millions of years old, and the processes that changed Earth in the past are the same processes that operate in the present.
Types of structures
Homologous - Structures that develop from the same embryonic tissue and have a similar structure but not necessarily a similar function Analogous - Body parts with a similar function but not a similar structure Vestigial - Organs so reduced in size that they are just traces, or "vestigals," of organs Ex: whale pelvis
Cladistic analysis
Identifies and considers only those chacteristics of organisms that are evolutionary innovations-new characteristics that arise as lineages evolve over time
How does Gram staining help to identify bacteria?
In Gram staining, a violet dye is first applied that stains the peptidoglycan cell walls; then an alcohol treatment is used to wash out the stain. Gram positive bacteria with thick peptidoglycan cell walls retain the violet, or purple, color. Gram negative bacteria with thinner cell walls appear red, or pink.
Law of Superposition
In undisturbed sedimentary rock layers, older layer lie beneath younger rock layers
Name the seven taxonomic groups in order from most generalized to most specific
Kingdom phylum class order family genus species
Genetic Engineering
Making changes in the DNA code of a living organism
Why are sex-linked disorders more common in males than in females?
Males have only 1 X chromosome and therefore all X-linked alleles are expressed in males, even if they are recessive
Recombinant DNA
Molecules of DNA produced by combining DNA from different sources
What two processes can lead to inherited variation in populations?
Mutations and genetic shuffling
What are obligate aerobes and obligate anaerobes?
Obligate aerobes: organisms that require a constant supply of oxygen in order to live Obligate anaerobes: must live in the absence of oxygen
Incomplete Dominance
One allele is not completely dominant over the other Ex: In "four o' clock" flowers, the red flowered and white flowered traits mix to form pink flowers in heterozygous plants
Extinction
When all of the members of a species die out
Competition
When animals struggle/compete for resources
Nondisjunction
When homologous chromosomes fail to separate
Reproductive Isolation
When the members of two populations cannot interbreed and produce fertile offspring Types: Behavioral - Two populations are capable of interbreeding but have different courtship rituals or other reproductive strategies involving behavior Geographic - two populations are separated by a geographic barrier Temporal - species reproduce at different times
