Flashcards in Biology 11 diversity Deck (94):
Name of person that developed the Binomial Nomenclature
-he created taxonomy (father of taxonomy)
The Science of Classifying organisms (including living and fossils)-->any type of organism
-Linnaeus: according to morphology similarities and a naming system (still used today)-->Taxonomic ranks
Phylogeny: Study of evolutionary relatedness between, and amoung species (similar to a large family tree).
-follows a lineage's evolutionary relationships among species through time
-Involves phylogenetic tree
Relatedness: based on similar characteristics, time, distances in time, common ancestors
7 main traditional taxonomic ranks
Function/purpose of a phylogenetic tree
-displays the evolutionary history of a species or a group of them
-shows the evolutionary relationships between and among species. It is a history of lineages of organisms as they change through time.
-relatedness between species
-species grouped into clades (Taxonomic group that includes a SINGLE ANCESTOR species and all of its DESCENDANTS)
-large (distant common ancestor)
-small (recent common ancestor)
Carl Linnaeus vs Carl Woese
-created/father of current classification and taxonomy
-created the binomial nomenclature (2 part name for classifying)
-He introduced a consistent way of grouping species according to their morphology (physical) similarities and a naming system (used today)
-identified the three domains (above the kingdoms)-->eubacteria, archaea, Eukaryotes
-Shows significant genetic differences
Highest taxonomic level of classification
What is a clade?
Monophyletic/Taxonomic group that includes a single ancestor species and all of its descendants -->members share one or more defining derived traits
Cladistics: HYPOTHESES on evolutionary relationships among clades
• If there are many possible ways that a group of clades can be connected, then the simplest evolutionary pathway is probably correct (derived traits evolved the fewest number of times) ←process called parsimony analysis (finding simplest path)
• Cladogram: type of evolutionary tree (showing evolutionary relationships/sets within sets of derived traits)
What are sister groups?
Sister groups: the two lineages that emerge from a node on a cladogram
What are taxonomic ranks?
Domain, kingdom, phylum, class, order, family, genus, species
Terms relating to oxygen and bacteria
-can survive without oxygen
-cannot live with oxygen
-need oxygen (aerobes)
-Can survive WITHOUT OXYGEN: facultative aerobes
-cannot live with oxygen: anaerobes
A group whose members are able to FREELY breed among themselves under NATURAL conditions
-->Biological species concept (exception to the definitions occurs for some animals and plants who undergo hybridization-cross breeding of two different species)
When traditional definition doesn't apply....
...Scientists classify organisms by morphology-Physical appearance and characteristics of an organism
• Individuals within a species can carry different traits both physical and genetic due to genetic variability and evolutionary changes
o Limitations: physical appearance can change
o Even same species, there are some difference
• Due to random assignment of genes
o Ex: humans (1% genetic difference/different looks)
• Known as individual variability: 1 species is different from others due to random assignment of genes
• All species within an ecosystem depend on one another to maintain biodiversity
• Food supply, protection, transportation, reproduction, hygiene, digestion
Taxonomy: science of classifying all organisms (including living and fossils)→ a system of naming and classifying species.
Carl Linnaeus created this way of classifying. He introduced a consistent way of grouping species according to their morphology (physical) similarities and a naming system (used today)
Linnaean system/binomial nomenclature
Species given a unique two-part name
-written in Latin
-either written in italics or underlined
-only the genus is capitalized
*Every species has a scientific name and common/broader name
-for untrained scientists
-Used to classify organisms based on morphology
-Large set of items is broken down into smaller subsets ultimately leading to the smallest available classification
Two ways: visual or descriptions
Current Taxonomy today
House Number: family
First name: species
Tree of life shows that... (connection)
Every single species is related to each other (either distant or closely related)
Biological Species Concept
• defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance
• two species may look the same, but if they cannot breed freely in nature, then not species
Characteristics of Prokaryotes
• Single celled
• Lack membrane bound organelles (no nucleus, mitochondria, chloroplasts)
• Smallest organisms on Earth (1-2 um long)
• Only about 10 000 prokaryote species have been isolated and identified (many are not identified -->many are archaea species)
Includes Kingdom Protista (some), Eubacteria and Archaea
Importance of Prokaryotes/bacteria
-Bacteria most common to us
-Responsible for many diseases in humans and organisms
Infectious bacteria called pathogens
Also infect livestock and crops, therefore threaten our primary food sources
Pathogens are harmful, however some diseases that harms certain species are beneficial to others
-Bacteria can also be beneficial
Decomposers, and producers (microorganisms and photosynthetic bacteria)-->bring nutrients back to soil (growth)
Humans rely on them to produce vitamin K and B12
Food: cheeses, yogurt (Ex: probiotic), soy sauce, chocolate
Insulin, HgH (human growth hormone)
-major groups (6)
6 major groups of Eubacteria:
Proteobacteria (purple bacteria) – photosynthetic
Green bacteria – photosynthetic
Cyanobacteria (blue-green algae) – photosynthetic
Gram Positive bacteria – cause many diseases
Spirochetes – cause syphilis (highly contagious, STD)
Chlamydias – cause chlamydia (STI)
Prokaryotic, mostly unicellular
Single loop chromosome of DNA found in nucleoid (no nucleus)
-Ribosomes scattered throughout cytoplasm
-Plasmid: small loop of DNA carrying a small number of genes -->changes to fight antibiotics
Genes not essential for cellular function but do provide advantages for the cell
Bacterial resistance to antibiotics
-One or more flagella (tails)
-Pili –hair (help cell attach to other cells or surfaces)
-Cell walls composed primarily of peptidoglycan
Large molecule that forms chains
Chains become cross linked making the cell wall strong
-Surrounded by a sticky capsule
Reduces water loss, resists high temperatures, and helps keeps out antibiotics and viruses
Three common shapes of eubacteria
Bacillus (rod shaped)
Spirillum (spiral) →rolling motion
Three common arrangements:
Clumps (staphylo) staphylococcus (groups of balls)
Kingdom Eubacteria classification
Autotrophic – make their own food
Heterotrophic – must eat their food
Most bacteria get their energy from sunlight (photoautotrophs), and chemical energy (chemoautotrophs), but can get it from hydrogen, sulfur, and iron
by oxygen requirements:
-obligate aerobes (need oxygen)
-facultative aerobes (without oxygen)
-others are obligate anaerobes (cannot live with oxygen)
Asexually: binary fission (do not need a mate)--> bacteria splits into two and each new bacterial cell contains the same replicated information
Bacteria mutate more often because they reproduce so quickly and transfer antibiotic resistance. (increasing genetic diversity if some bacteria have different codes
Gain new DNA by conjugation (transfer of plasmids) →horizontal gene transfer takes place (Pili is used to link two bacteria temporarily)
Kingdom Eubacteria diseases
Caused by releasing toxins: botulism (toxin in botox; fatal at high doses), Ecoli (bad and good O157)
Antibiotics (get rid of bacteria)
o Bacteria can produce antibiotic substances as a form of chemical warfare
o Immensely valuable to humans
o May not be so valuable in the future because the bacteria adapt and become resistant
Kingdom Eubacteria unique
*Special because prokaryotes can live in a wider range of habitats than eukaryotes and are the earth’s most abundant organisms
small kingdom, hard to find
• Cell walls that lack peptidoglycan
• Inhabit extreme environments
• Reproduce: asexually
• Single celled (that we know of)
• Cell walls and membranes much more resistant to physical and chemical disruptions (because they live in extreme environments)
• 3 groups: euryarchaeota, crenarchaeota, korarchaeota
• Examples: thermophiles (inhabit in extremely hot environments)
Traditional vs modern classification
Traditional classification: morphology (Linnaean)
• Based on morphological traits
• Does not accurately estimate the degree of relatedness between species
Modern biological classification: Phylogeny
• Purpose: shows the degree of relatedness between species
• Allows for understanding of evolutionary history
-what are viruses?
• Complete virus: Viron
• Purpose: to deliver DNA or RNA genome into a host cell
• An obligate intracellular parasite (no metabolic machinery of its own and can multiply only inside living host cells)
• Are small, infectious particles
• Contains genetic material in the form of DNA or RNA within a protein capsule
• No cytoplasm
• Cannot grow or reproduce on their own (needs host cell (Non-living))
o Once inside of the host, the DNA or RNA are injected/released and begins to overtake the cell
o Cell eventually makes copies of the virus to overcome host
Structures: DNA or RNA surrounded by proten coat
Viruses vs Bacteria
viral diseases more common (less vaccines than antibiotics)
*viruses replicate a lot quicker than bacteria
-->immune system fights off viruses
-Vaccines target immune system
*separate viruses/vaccines with bacteria/antibiotics (go after bacteria)
*bacteria do not need hosts
In humans not the greatest, as most diseases can lead to undesirable symptoms even cancer
In ecosystems, diseases control populations (beneficial)
Cause diseases through injecting DNA or RNA into host cells within organisms and thus infecting the organism
Infection: one organism enters another and replicates in it.
Disease: when the activities of the “guest” interferes with the host’s normal functions
Own body cells, tissues, organs etc. being damaged, destroyed, harmed results in an abnormal state of function
Ex: AIDS, measles, meningitis
Based on shape, size, and type of genetic material (DNA or RNA)
• Classified into orders, families, genera, and species
• Can infect only a single host, single organ system or single tissue
o Ex. HIV infects only certain immune cells
• Viruses that infect bacterial cells are called bacteriophages
• Inject their DNA into the bacterium, and protein capsid stays outside
dormant and non-dormant (active)
Dormant activated during times of stress (i.e. herpes)
Cure for virus diseases
Vaccine: Mixtures that contain weakened forms (not small dosage) or parts of dangerous viruses
Trigger a response by the immune system without causing infection
This allows the body to react quickly when exposed to the virus again
Allows body to be prepared and adapted
Some diseases are difficult to provide viruses for because the structure of the virus provides an obstacle, or the virus continually changes
Ex. HIV, influenza
Benefits of viruses
Lower the numbers of harmful bacteria – gene therapy
Gene therapy is the method of treating disease in which genes are introduced into cells to replace, supplement, or repair a defective gene
Use viruses to deliver drugs or genes to target cells
Use viruses in gene therapy to target certain cells -->kill off cells that are undesirable
Place drugs inside virus capsules or preplace viral DNA with DNA they want to insert into a host cell
*Taking advantage of viruses ability to hold onto host cells
-using virus capsule to deliver drugs: chemotherapy
-using virus to insert new copies of genes: genetic disorders (corrective genes)
-using virus to insert gene taken from one species to another species (genetically modified organisms, common in plants)
Small infectious pieces of RNA (no DNA)-->a strand
Smaller than any virus
RNA does not code for any proteins
Viroids are PLANT pathogens that can destroy entire fields of crops
Interfere with RNA of the host cell
Abnormally shaped proteins found in the brain and nervous tissue of infected animals
When eaten by other animals, the prions enter the animals bloodstream and go to its brain
The prions interact with normally shaped proteins and cause them to function abnormally
Brains of affected animals are full of spongy holes
Ex. Mad cow disease (BSE) or Creutzfeldt Jakob disease (CJD)
(Simple) Eukaryotic organisms that appeared 1.5 billion years ago.
Very diverse species leads to difficulties with classification.
E.g., Classification based on nutrition:
o Reproduction: asexually and sexually (under adverse conditions)
Asexually: budding, binary fission, spore-formation
Have a nucleus and organelles bound by membranes
Internal membranes likely developed from the folded cell membrane of an ancestral prokaryotic cell. This increased the cell surface area, allowing the cell to better exchange materials with its environment
Necessary feature of large cells
Mitochondria and chloroplasts thought to have originated from Protists (own DNA within organelle)
The process of endosymbiosis (absorption of little cell by larger cell)
Single celled organism lives within the cells of another organism
-metabolism (how get food and energy)
-uni or multi
• Predominantly unicellular.
• Lack cell walls
• Live in aquatic ecosystems, wet soil or fluids within a host.
• Some are parasitic.
• Causes sleeping sickness in Africa.
Ex: amoeba and paramecium
• Predominantly decomposers.
• Feed via endocytosis.
• Live in cool, damp habitats.
• Cannot exist in hot or dry places
Ex: water mould
• Contain chlorophyll.
Ex: euglena, algae
Kingdom Protist interactions
Producers or consumers
Photosynthetic producers are the primary producers in aquatic ecosystems
Climate change is affecting many protists, including algae
Aquatic temperatures are rising and water is becoming more acidic interfering with some protists’ ability to produce their outer shells
Can live in colonies (consists of cells living together)
Ex: volvox (type of green algae)
o Cycling of materials/nutrients through biosphere
•Engage in symbiotic relationships with plants
o Mainly mutualism (both benefit)
o Commensalism (one benefits, other is not harmed)
o Parasitism (one benefits, other is harmed)
• Play a role in animal/plant diseases (spread disease)
• Involved in food (Ex: mushroom)
• Role in beer and wine production (ferment)→Yeast
• Involved in drugs (penicillin, anti-rejection)
-Live in what environments
-Primarily multicellular. (A couple single cellular (Yeast))
• Heterotrophic (saprobes). →eat dead organic material
-Secrete digestive enzymes on organic matter and absorbing the resulting breakdown products (called extracellular digestion and absorption)
-Sexual and asexual reproduction (reproduce at any time)
-Cell wall contains chitin
o Long strains of small stick like molecules that are close together *beetle shell is made of chitin
•Body of multicellular Fungi composed of hyphae: reproductive component of fungus (cobweb structure that spreads -->cannot be seen by naked eye)
oMass of branching, thread-like hyphae is known as mycelium
o Mycelium absorbs nutrients from food.
• Active reproductive part of fungus
• Inhabits in environments that are damp, moist, warm, room temperature (do not like dry places)
Classification: patterns of sexual reproduction
Phylums/divisions of Fungus (4)
Phylum Zygomycota: Spores in a case-like (square) structure (sporangium)
Phylum Ascomycota: Spores in a sac-like (circular) structure (ascus)
Phylum Basidiomycota: Spores in a club-like (rectangle) structure (basidium).
Phylum Chytridiomycota: Swimming spores (aquatic environments)
reproduction: sexually and asexually
Sexually: Develop from embryos protected by parental tissue. -->requires a male and female plant part
-cell wall: cellulose
-can survive in a range of habitats
•The earliest land plants may have evolved from algal-like organisms. (charophytes )
*since algae do not have cell walls contain cellulose and do not develop from embryos protected by parental tissue, they are not considered a plant
-top and most important producers in an ecosystem
-All photosynthesize (Photosynthesis)
-Provide organisms with places to live
– Structural diversity: giving other organisms a place to live
-Used in Medicines
-Provide Paper products
-Food (no energy from plants, instead minerals and antioxidants)-->component of fibre
*common name: moulds
• Spores in a case-like (square) structure (sporangium) -->can be spread because of airborne
• Most are soil fungi (near trees)
• Many are used commercially
• Include familiar bread and fruit moulds
• Many are parasites of insects
Example: Bread Mould (case-like fungi)
– Spores in a sac-like (circular) structure (ascus)
– Many like yeast are USEFUL to humans (bread, beer, wine)
Example: Mildews, some moulds and yeasts
Penicillin mould: Alexander Fleming discovered that the mould releases chemicals, which inhibit bacteria growth
important for bread, beer, wine industry
Asexual reproduction via budding: small cell forms on parent cell than is released
Sexual reproduction: less favourable/forms ascospores. -->remain dormant until conditions improve (because cannot thrive in environment so therefore go to sleep)
– Spores in a club-like (rectangle) structure (basidium).
– Include mushrooms, puffballs
– Most are decomposers
– Some for symbiotic relations with plants
Examples: Mushrooms, puffballs, rusts (cause disease to plants→dots on leaves), bracket fungi (grow on trees)
-Have gills that are made up of basidia (have thousands of spores)
-wind disperses spores
– Swimming spores (aquatic environments)
– Most are saprophytes (heterotrophic)
– They can be single or multi-cellular
Asexual and sexual reproduction
Fungi reproduce both asexually and sexually by making spores
• Asexual used to produce spores via mitosis in sporangia (spore-forming chambers) at the tips of specialized haploid hyphae
• Unicellular: Asexual via budding
• Fragments of hyphae can grow into new colonies
• Sexual: fusion of two haploid nuclei produces a diploid zygote. Later on, a spore-bearing structure forms and releases spores that germinate and grow into a new mycelium
Bread mould example (from phylum zygomycota)
• Asexual reproduction:
• Sugar feeds mould
o Hyphae extends along surface and into food.
o Absorb water and sugar.
o Black sporangia form.
o Each contains thousands of spores.
o Spores dispersed via wind.
• Occurs under less favourable conditions (frozen)
• Two genetically different hyphae are produced.
• Upon contact a (zygospore) forms.
• Remains dormant until conditions improve.
•MUST be in a relationship with something else in order to function
-Mutualism (both species benefit from relationship)
• Ex: lichen (has place to live) and tree trunk (gets nutrients)
o Lichen: composite organism consisting of a fungus and a single celled alga or a cyanobacteria
• Mycorrhizae: a symbiotic relationship between mycorrhizal fungus and roots of a vascular plant. Fungus forms a mesh and colonize the plant's root system and create a network that increases the plant's capacity to absorb (increase surface area)
o Fungus takes up nutrients and shares them with the plant
o Plant gives sugar to fungus
-Commensalism (one species benefits without affecting the other organism) -->clown fish and anemone
-Parasitism (one species benefits and the other is harmed) -->ticks, lice
Kingdom Plant Types
Non vascular (byrophytes)
o Do not have xylem and phloem (not as tall)
o Ex: mosses, liverworts, hornworts
o Lack true roots, stems, leaves and vascular tissue
o Environment: moist
o *very short in size (cm) (due to lack of vascular tissues etc.)
o Reproduction: sexual (spores) or asexual (vegetative propagation: growth of new roots and shoots from extensions or fragments of a parent plant; form of asexual reproduction in plants)
• Can reproduce at the same time
-Sexual: requires water for sperm to swim to egg. They produce a sporophyte that releases spores (which germinate).
o These plants are very well-adapted to life on land.
o Have xylem and phloem (vascular tissues)
• Conducting tissue
• Xylem: transports water and minerals
• Phloem: transports food (carbohydrates, glucose from photosynthesis)
• Allow for greater heights in plants (due to system)
-spore producing -->asexual and sexual reproduction (water release spores)
Types of vascular plants
Ex: club mosses, ferns, horsetails
• No flowers
• *all like water environments
• Asexual and sexual reproduction (need water)
• Most successful plants on Earth.
• Due to specialized leaves, stems and roots.
• Sexual reproduction occurs via pollination. →require male and female
• Does not require water.
• Seeds withstand desiccation.
•Class Gymnosperms (conifers), Angiosperms (flowering plants)
Kingdom Plant sexual reproduction (seed producing vascular plants)
Requires male and female parts in order to be fertilized
o Pollen dispersed by wind.
o Pollen produces sperm when contact is made with seed cone.
o Sperm fertilizes ovules.
o Zygotes grow into seeds.
o Pollon from male blows into female pinecone -->however seed not always grow (must be pollinated by male first, then can grow)
• Ovum fertilized by sperm (from pollen).
• Zygote develops into an embryo contained in a seed.
• Seeds are enclosed in a fruit.
• Seeds must be released from fruit in order to germinate.
• needs to be fertilized by a male plant in order for seed to grow
• Seed fertilizer on grass forces sexual reproduction of plants (fertilizes seed)
When two touch due to wind, fertilize female
•Requires insect to take pollen from female stigma of one plant to the male anther of another plant
pollen -->becomes sperm-->fertilize ovule-->ovule develops into a seed (zygote: fertilized egg: grow into seeds)-->seed is ready to grow (must be outside of fruit in order to germinate-->angiosperms)
Reproduction for nonvascular plants and spore producing vascular plants
-sperm swim from antheridium (male reproductive organs) to archegonium (female reproductive organ) to fertilize egg.
• In presence of sperm and egg cell in order to sexual reproduce (need male and female plant)
• #1 importance: dependency for survival →due to predator/prey relationship →every animal depends on each other
• Depend for Food
• Pollination: insects
• All heterotrophic, all multicellular, all eukaryotes (have membrane bound organelles, complex)
• Lack cell walls (plants, fungi, bacteria, archaea have cell walls)
• Specialized nervous & muscle tissue.
• Primarily sexual reproduction
• Undergo Aerobic respiration
o (require oxygen to survive)
• Specialized Cell Development
o Germ layers (layers of cells in a developing embryo)
• 3 simple tissues (ectoderm, endoderm, mesoderm)
• Ectoderm gives rise to the skin and nervous tissue (outer)
• Endoderm gives rise to the inner lining of the gut and in some organisms the respiratory system (inner)
• Mesoderm gives rise to the circulatory, reproductive, excretory, and muscular systems (middle)
• * Only species on planet (gestation/development time is longàtakes time to develop)
• Common ancestor: also colonial flagellated protist (700 million years ago) →choanoflagellates
Classified based on body plan (how body is organized)
o 1) Body symmetry: asymmetrical (not symmetrical), bilateral (line of symmetry divide into two) or radial (cross lines can divide)
• Radial: starfish, jelly fish
• Bilateral: humans (not organs though)
• Early: asymmetrical →radial →bilateral (common)
o 2) Degree of cell organization: function independently or form tissues and organs.
• Some organisms Function independently without tissues and organs
o 3) Presence of a coelom (internal body cavity)-->skeletal system.
Invertebrates vs vertebrates
-Invertebrates: do not have backbone
-Vertebrates: have backbone
Simplest invertebrates (phyla)
Characteristics of each
Phylum Sponges (poifera):
o Most primitive animals. (oldest) →no tissues or organs
o All aquatic (freshwater) and mostly marine (sea/ocean).
o Sessile (cannot move)
o Simple, asymmetrical body plan.
o No mouth, digestive cavity -->have muscles and nervous system.
o Have pores
Reproduce asexually or sexually:
o Reproduce Sexually:
• Many are hermaphrodites: animal that produces both eggs and sperm
• (No mate, but have different sex organs)
o Reproduce Asexually: Budding (break away and grow into new sponges)
oCells organized into tissues.
o E.g., jellyfish, sea anemones and corals.
• Sting by toxic chemicals (paralyze)
oMouth/anus leads to gastrovascular cavity→saclike cavity that functions in digestion and gas exchange in cnidarians and flatworms
• Where digestion, circulation and gas exchange occur.
oReproduction: Lifecycle mostly alternates between asexual sessile polyps and sexual free-swimming medusas.
• Asexual: polyps tentacles (some corals)
• Budding (forms new polyps)
• Sexual: Medusas (jellyfish)
• Produce small polyps via sexual reproduction
• Produce egg or sperm
-all have bilateral symmetry
o Sense organs and nerve cells located at anterior end. (concentration of nerve cells at one end of the body)
oCoelom (fluid-filled body cavity).
o Ex: worms
6 major phyla:
1. Arthropods: not insects
• Segmented bodies. (put together in pieces)
• Exoskeleton (composed of chitin):
o A waterproof carbohydrate.
o Protects animal.
o Resists desiccation.
• Blood cavity.
• Have full respiratory and circulatory system (becoming more complex)
• E.g., scorpions, spiders, mites and ticks.
• E.g., shrimp, lobsters, crayfish and crabs.
• E.g., fly, mosquito, beetles
• Nematodes also known as roundworms.
• Scavengers in soil and found at bottoms of lakes and ponds.
• Some are parasitic.
• *found after rain
3. Segmented worms:
• Live in marine, freshwater and terrestrial environments.
• Segmented bodies and a coelom. (slight skeletal system/rings)
• Segmentation allows for larger growth and enhanced locomotion (ability to move).
• E.g., Earthworms and leeches.
o *segmented: divided into segments
• No coelom due to flattened body (have fluid but no skeletal system) -->very flat
• Marine parasites.
linage of bilateral animals in which the second opening on the embryo surface develops into a mouth (first develops into anus)
Two main groups: phyla
Echinoderms (starfish, sea urchins, sea cucumbers)→invertebrates
Phylum Echinoderms: Marine animals
• Exhibit same embryonic development as vertebrates (same as us)
• Immature (not full grown) echinoderms take on a free swimming bilateral form, whereas as they mature they develop a radial form
o Start off bilateral, mature into radial
• Complete digestive system, simple circulatory system, no respiratory or excretory systemàlive underwater
• No head regionà nervous system circles the mouth and extend into the arms (as well developed system as human but smaller)
All Embryos Have the Following Features:
1. Notochord – dorsal supporting rod(almost like a spine) that is found in all embryos of chordatesàspinal chord
2. Hollow Dorsal nerve cord (parallels the notochord)
3. Pharyngeal gill slits – precursor to gills in aquatic animals, but lost before birth in terrestrial animals (first developed)
4. Post-anal tail
* Humans did have gills and post-anal tail when developing
• Bilaterally symmetrical (body symmetrical when divided in half)
• Ventral Heart (on one side)
• Coelom (skeletal system)
• Endoskeleton (internal skeleton) with muscles attached for locomotion (swimming, creeping, running, jumping, flying, etc.)
• Sexual dimorphism in most species (males and females have different appearances)
• Class: Jawless fish Ex: hagfish, lampreys
• Class: Cartilaginous Fishes Ex: sharks, rays, skates
o Skeletons made of cartilage (flexible movement)
• Class: Bony fishes: Ex: trout, salmon, tuna (any fish with bone)
o Contain internal air sacs, called swim bladders, for buoyancy (lungfishes can also use them for Respiration)-->swim above bottom of water (float)
• Class Amphibia: Ex: frogs, toads, newts, salamanders, mudpuppies
o Water (first born) & land (terrestrial)
• Class Reptilia: Ex: Lizards, snakes, crocodiles, alligators, caimans, turtles, tortoises, and dragons
oSuccessful Adaptations to Terrestrial Life:
– Skin modified into thick scales to prevent desiccation;
– Breathing and gas exchange occur via lungs
– Kidneys secrete concentrated urine to conserve water;
o – Eggs are amniotic (have yolks) and have waterproof shells.
• Amniotic: reptile, bird, or mammal
• Amniotic egg: egg with internal membranes that allow the amniote embryo to develop away from water
• Yolk: animals are nourished by a yolk (increase the time that the egg takes to hatch)
• Allowed for greater organization of tissues (longer gestation period)
o – No larval stage
o – No larval stage
o – Turtles, snakes, and lizards have a partial septum dividing ventricle, so 3-chambered heart functions more like 4-chambered heart;
– Crocodilians have a 4-chambered heart
o * land and water
• Class Aves: birds
o About 8,700 species.
o • Endotherms – generate own body heat (all other animal classes so far have been ectotherms – need to absorb heat from surroundings).
o • Oviparous, lay large amniotic eggs with hard shells, and young do not metamorphose.
Adapted to Life in the Air:
o Tetrapods (4 first limbed vertebrates) but forelimbs modified into wings for flight
o Deep, keel-like breast bone to provide arge surface area for flight muscle attachment
o Skin has specialized structures: feathers
o Bones are strong, but hollow to reduce body weight
o Breathing occurs via lungs, but lungs have several air sacs to provide buoyancy during flight
*can be flightless birds
– Evolved from scales
– Down feathers for insulation
– Contour feathers for flight (provide lift and stability)
o Ex: humans, dolphins, cat etc.
o Highest classification of specialty of all kingdoms and classes
o No scales or feathers (hair or fur)
Three groups of classification: order
1. Monotremes – a small group with exceptions to many of the mammalian “rules”.-->Not follow many rules
o Lay eggs
o Ex: platypus, echidna
2. Marsupials – the “pouched” mammals who have an abbreviated gestation. (Kangeroo)→live birth
3. Placentals – mammals who’s young develop inside a placenta for a complete gestation -->most mammals like humans, bears, bats etc.
Amniotic: eggs that have yolk
Swim bladders: bony fish- internal air sacs for buoyancy
Endotherms: animals that can generate own heat
Ectotherms: animals that need to absorb heat (cannot generate own heat)
Down feathers: insulation
Contour feathers: flight, lift, stability
Oviparous: animals that can lay eggs
Gastrovascular cavity: Saclike cavity where digestion, circulation and gas exchange occur.
1) Species diversity
• Variety and abundance of species in a given area
• Variety in heritable characteristics in a healthy breeding population
• All different types of genes in the earth lead to species diversity
o Resistance to diseases
• Populations lacking genetic diversity are prone to disease than higher diversity
o Conservation of endangered species
• Take species from another population and add it in to introduce new genes
3) Ecosystem diversity
• Variety of ecosystem in the biosphere
o Ecosystem: result of biological, climatic, and geological and chemical ingredients in an area
More biodiversity a place is --> more chances are there for species to survive (sustainability). If one food source is being interrupted, having a wide biodiversity in that area will allow higher animals to survive through a different food chain route.
Topic on classification of birds/dinosaurs/crocodiles
Because of bird's distinct features→classified in own taxon class Aves
• Fossil evidence links them closely to a group of carnivorous dinosaurs and therapods (bipedal carnivores with feathers)
• Morphological and genetic evidence suggests that their closest living relatives are crocodiles (similar skeletons, scales→reptiles, four chambered hearts, care for young)
Birds and dinosaurs:
• Evidence of feathered species connection
• Archaeopteryx (early bird)
Characteristics of crocodiles:
• Only reptile with four chambered heart
• Same skeletal features shared with only dinosaurs and birds
• Care for their young
• Class Reptilia is not a clade without Class Aves
o Because two classes share a common ancestor (dinosaur)
o Because in same clade, which must include all the descendants of ancestors, including birds
• Alligators and birds both have air flows in a single direction through tubes
• Protein found in the connective tissues connects birds and reptiles to dinosaurs than respiratory system
Unicellular vs multicellular
• Organism that consists of 1 cell
• Do not have membrane bound organelles
• Have nucleoid
• Simple in structure
• Size very small
• Can exist in extreme environments
• Prokaryotic (typically)
• Ex: all bacteria, amoeba & paramecium (protist), yeast (fungus)
• Organism that consists of more than 1 cell
o Due to endosymbiosis (origin of eukaryotes): mitochondria and chloroplasts both contain own DNA (similar to DNA in bacteria), are surrounded by two membranes, very small
o Endoplasmic reticulum and nuclear envelope may have been evolved from internal infoldings of the plasma membrane of an ancestral prokaryotic cell
o Mitochondria was engulfed by a larger primitive cell
o Chloroplasts lived in early eukaryotic cells (chloroplasts of green algae evolved from cyanobacteria)
• Complex in structure
• All Eukaryotic: have membrane bound organelles
• Size varies (not microscopic)
• Ex: all animals, all plants, most fungi, some algae
Importance of conifers
• Referred to as “softwood”.
• Accounts for 50% of Ontario’s forests.
• Canada supplies 20% of world’s softwood.
• A lot of soft wood, huge industry for Canada (contributing to deforestation) →pulp and paper
Angiosperms vs gymnosperms
Angiosperms have seeds encased in a tissue known as fruit; gymnosperms have seeds that are no encased
-->angiosperms most dominant group of plants
What is a seed? Plants
Seed: include a plant embryo, its food supply, and a tough, protective casing.
Gymnosperms: produce seeds in carrying out reproduction
Angiosperms vs gymnosperms
Angiosperms have seeds encased in a tissue known as fruit; gymnosperms have seeds that are no encased
Benefits and drawbacks from eubacteria
-cause diseases that control population numbers
-intestinal tract (E.coli in large intestine; help break down food i.e probiotic yogurt bacteria)
-commercial uses (food-->chocolate, soy sauce etc.)
-produce vitamin K and B12
-cause diseases (i.e. pathogens) that affect our food sources (crops, live stock)
-diseases pose a threat to immune system
-hard to get rid of (rapid reproduction)
1) Virus invades organism
2) Once virus enters organism, virus attaches to cells
3) Virus injects own genetic information (DNA/RNA)
4) Virus takes over host cell
5) The Virus’s genetic information programs cell to make more viruses
6) When cell reproduces, it will make more viruses
Protists other info
Brown algae: marine multicellular algae Size: microscopic filaments to 30 m kelp
Plasmodium: protist pathogen that causes malaria
General characteristics of terms:
-photosynthetic (usually contain chloroplasts)
-lack cell walls
-live in damp/moist environments (not hot or dry)
-heterotrophic (mainly decomposers)
Main importance of:
-cause diseases (can be beneficial or harmful)
-diseases control populations, bring harm to food sources and body
-bridge the gap between prokaryotes and eukaryotes
-Original eukaryotes (early ancestors to plants and animals)
-share many characteristics of both prokaryotes and eukaryotes
-decomposers (contribute to cycling of materials/nutrients through biosphere)
-producers (via photosynthesis; make up bottom of food chain)
-dependency for survival (rely on each other to survive)
-fungi that have not been observed to reproduce sexually
Ex: Human Pathogens
• Feed on outer layers of skin
– No known sexual phases.
Example: Trichophyton rubrum
• Causes athlete’s foot.
• Lives in warm, damp places (floors of showers and pools).
• Symptoms: reddened, cracked and peeling skin; itching, burning and stinging
• *Fungus is doing its job by trying to get rid of dead material. The Fungus eats the dead skin
Complexity in Animals
•Number of germ layers developed during embryo stage
•Presence of Coelom
Simple to complex animals
7. Segmented Worms
When talking about relationships on phylogenetic tree...
-look at distance between species: closer means that they have a more recent common ancestor and they share similar characteristics
-farther away lines mean that the two species have more different characteristics (each branch represents an evolutionary change)
Plasmid in eubacteria
single loop of DNA that carries antibiotic resistance information. It is separate from the nucleoid and is transferred between cells during conjugation.
Fermentation: is a metabolic process that converts sugar to acids, gases and/or alcohol.
Occurs in yeast and bacteria, but also in oxygen-starved muscle cells, as in the case of lactic acid fermentation.
Bacteria, viruses have the ability to...
Have ability to become dormant/inactive when environments are not supportive
-->explains why diseases appear gone, but then reappear again.
Purpose of releasing large quantities of spores and seeds etc.
To ensure growth and a new generation of the species.
Only a tiny fraction of the spores, seeds will germinate and grow successfully. Also, only some sperms will reach the egg (therefore need a lot of them)
Why is a coelom such a valuable feature?
Allows for the development of complex organisms and organs.
Coelom adds support, space and suspends the organs, allowing them to grow into very complex organs.
Effects of amniotic egg
• Allowed for greater organization of tissues (longer gestation period)
-egg with internal membranes that allow the amniote embryo to develop away from water
-egg has evolved into our current animal classifications (vertebrates and chordates, classes within chordates)