Chapter 26: Phylogeny and the Tree of Life

26.1: Phylogenies show evolutionary relationships

• Phylogeny: Evolutionary history of a species

• Systematics: Method focused on classifying organisms and determining their evolutionary relationships

• Binomial: Two part format of a scientific name

  • Genus: First part of binomial of scientific name

• Species → Genus → Family → Order → Class → Phylum → Kingdom → Domain (most to least specific)

• Taxon: Named group at any level of the hierarchy

• Phylogenic Tree: Branching diagram for evolutionary history of organisms

• Branch Point: Represents common ancestor of two evolutionary lineages diverging from it

• Evolutionary Lineage: Sequence of ancestral organisms leading to a particular descendant taxon

• Sister Taxa: Groups of organisms that share an immediate common ancestor not shared by any other group

• Rooted: A tree where there is a branch point all the other animals come off

• Basal Taxon: Lineage that diverges from other members of its group early

1. Equal, since the nodes branch off at the family

2. C, since the things can rotate around nodes but can’t switch branch shapes

3. Can’t draw

26.2: Phylogenies are inferred from morphological and molecular data

• Homologies: Phenotypic and genetic similarities due to shared ancestry

• Analogy: Similarity between organisms due to convergent evolution

• Organisms with similar morphology or DNA are more likely to be closely related

• Computer programs can distinguish DNA sequences

26.3: Shared characters are used to construct phylogenic trees

• Cladistics: Approach to systematics, common ancestry prioritized

• Clades: Groups that scientists try to place species into

• Monophyletic: A taxon that consists of an ancestral species and all of its descendants

• Paraphyletic: Group consisting of ancestral species and some, but not all of its descendants

• Polyphyletic: Distantly related species but doesn’t include most recent common ancestor

• Shared Ancestral Character: Characteristic that originated in an ancestor of the taxon

  • ex. all mammals have backbones but so do other animals, the backbone is broader than it so for mammals its a shared ancestral character

• Shared Derived Character: Character unique to a clade

• Outgroup: Species or group of species not part of the group of species, least recent common ancestor

• Maximum Parsimony: First investigate simplest explanation that is consistent with the facts

• Maximum Likelihood: Identify tree most likely to have produced a set of DNA based on probability rules

1. It would not be, since it is shared between all mammals

2. Idk

3. Can’t draw

26.4: An organism’s evolutionary history is documented in its genome

• Orthologous Genes: Homology is from a speciation event

• Paralogous Genes: Homology is from gene duplication

• Distinctly related species have many orthologous genes

• Variation in number and complexity of genes between species suggests they are versatile and have many functions

1. Seeing whether it’s orthologous or paralogous can tell us if it was speciation or gene duplication

2. Orthologous genes

3. Too lazy to go back

26.5: Molecular clocks help track evolutionary time

• Molecular Clock: Approach estimating age divergence from a common ancestor by looking at DNA

• Some regions of DNA change at a rate consistent enough to serve as a molecular clock

  • Other DNA regions change in a less predictable way

• Molecular clock analyses suggest that the most common strain of HIV jumped from primates to humans in the early 1900s

26.6: Our understanding of the tree of life continues to change based on new data

• First, there were five kingdoms, prokaryotes, unicellular organisms, plants, fungi, and animals

  • Prokaryotes were too different from each other so the three domains, bacteria, archaea, and eukarya were made

• Horizontal Gene Transfer: Process genes transferred transferred from one genome to another

  • Genetic analyses indicate it has occurred throughout evolutionary history

1. Too broad

2. Depends on what you’re looking at, like RNA or DNA, etc.

3. Endosymbiosis, they transferred genes to each other

Chapter 27: Bacteria and Archaea

27.1: Structural and functional adaptations contribute to prokaryotic success

• Prokaryotes: Single celled organisms that make up domains Bacteria and Archaea

  • First orgaisms to inhabit Earth, almost 2.5 billion years ago

  • Unicellular, with diameters of 0.5-5 µm

    • Eukaryotic cells have diameters of 10-100 µm

  • Many different shapes—cocci (spherical), bacilli (rods), spiral

• Peptidoglycan: Polymer composed of modified sugars cross linked by short polypeptides, used in bacterial cell walls instead of cellulose or chitin (like in eukaryotes)

• Archael cell walls have polysaccharides and proteins but no peptidoglycan

• Gram Stain: Technique to categorize bacterial species according to differences in cell wall composition

  • Samples are stained with crystal violet dye and iodine, then rinsed in alcohol, then stained with red dye safranin, which enters the cell and binds to its DNA. Staining response is due to bacterium’s cell wall structure

  • Gram Positive Bacteria: Simple walls composed of a thick layer of peptidoglycan

  • Gram Negative Bacteria: Less peptidoglycan, structurally more complex, outer membrane has liposaccharides (carbohydrates bonded to lipids)

• Capsule: Sticky layer of polysaccharide or protein that surrounds the cell wall of many prokaryotes that is dense and well defined

  • If it’s not dense and well defined it’s a slime layer

  • Used to let prokaryotes adhere to substrates or other individuals and protect against dehydration

• Endospores: Resistant cells developed by bacteria when they lack water or essential nutrients

  • Original cell makes a copy of its chromosome and surrounds the copy with a multilayered structure

    • Water is removed from the endospore so metabolism halts and original cell lyses, releasing the endospore

• Fimbrae: Hairlike appendages that some prokaryotes use to stick to their substrate or to one another

  • Short and more numerous than pili

• Pili/Sex Pili: Appendages that pull two cells together prior to DNA transfer between cells

• Taxis: Directed movement toward or away from a stimulus, ~half of prokaryotes can do it

  • Prokaryotes that exhibit chemotaxis change movement in response to chemicals, may move towards nutrients or oxygen, positive chemotaxis, or away from toxic substances, negative chemotaxis

• Flagella may be scattered over the entire surface of the cell or concentrated at one or both ends, and differ greatly from eukaryotic flagella

  • 1/10 the width, not covered by an extension of the plasma membrane, different molecular composition and mechanism of propulsion

  • Bacterial and archael flagella have different and unrelated proteins

  • All three must have arose independently

  • Three parts, motor, hook, and filament hat are composed of 42 different kinds of proteins

• No complex compartmentalization like in eukaryotic, but do have membranes that perform metabolic functions, which are usually infoldings of the plasma membrane

• Genome has much less DNA than eukaryotic

  • One circular chromosome, eukaryotes have many linear chromosomes

  • Lack a nucleus, chromosome is located in the nucleoid

  • Smaller rings of independently replicating DNA molecules, plasmids, most only carrying a few genes

27.2: Rapid reproduction, mutation, and genetic recombination promote genetic diversity in prokaryotes

• Genetic Recombination: Combining of DNA from two sources

  • In prokaryotes, transformation, transduction, and conjugating bring together prokaryotic DNA from two individuals

• Transformation: Genotype and possible phenotype of prokaryotic cell are altered by uptake of foreign DNA in its surroundings

• Transduction: Phages carry prokaryotic genes from one host cell to another

• Conjugation: DNA is transferred between two prokaryotic cells that are temporarily joined

• F(ertility) Factor: Piece of DNA whose presence results in the ability to form pili and donate DNA during conjugation

  • F Plasmid: F Factor in its plasmid form

    • Cells with F plasmid function as DNA donors during conjugation

• R(esistance) Plasmids: Carry genes that code for enzymes that specifically destroy or hinder effectiveness of certain antibiotics

27.3: Diverse nutritional and metabolic adaptations have evolved in prokaryotes

• Obligate Aerobes: Must use O₂ for cellular respiration and can’t grow without it

• Obligate Anaerobes: Poisoned by O₂

  • Some live exclusively by fermentation, others use anaerobic respiration

  • Anaerobic Respiration: Substances other than O₂ are the final electron receptors

• Facultative Anaerobes: Use O₂ if it is present but can also do fermentation or anaerobic respiration

• Nitrogen Fixation: Some cyanobacteria and methanogens convert atmospheric nitrogen to ammonia

  • This is then incorporated into amino acids and other organic molecules

• Heterocysts: Carry out nitrogen fixation

  • Surrounded bu a thickened cell wall that restricts entry of O₂

• Biofilms: Surface coating colonies where metabolic cooperation among cells of 1+ prokaryotic species often occurs

27.4: Prokaryotes have radiated into a diverse set of lineages

• Extremophiles: First prokaryotes assigned to domain Archea, live in extreme environments that few other organisms can survive in

  • Extreme Halophiles: Live in highly saline environments

  • Extreme Thermophiles: Thrive in very hot environments

• Methanogens: Archaea that release methane as a byproduct of jpw tjeu pntaom emerhu

27.5: Prokaryotes play crucial roles in the biosphere

• Decomposers: Chemoheterotrophic prokaryotes that break down dead organisms and waste products, unlocking supplies of carbon, nitrogen, and other elements

• Symbiosis: Ecological relationship where two species live in close contact with each other

  • Host: Larger organism in symbiosis

  • Symbiont: Smaller organism in symbiosis

  • Mutualism: Ecological relationship in which both species benefit

  • Commensalism: Ecological relationship which one species benefits while the other isn’t harmed or helped

  • Parasitism: Parasite feeds on cell contents, tissues, or body fluids of the host

    • Pathogens: Parasites that cause disease, usually prokaryotic

27.6: Prokaryotes have both beneficial and harmful inpacts on humans

• Bacteria cause ~half of human diseases

• Pathogenic prokaryotes cause illness by producing poisons (exo and endotoxins)

  • Exotoxins: Proteins secreted by certain bacteria and other organisms

  • Endotoxins: Lipopolysaccharide components of the outer membrane of gram negative bacteria, released only when bacteria die and cell walls break down

• CRPISPR-Cas9 System: Introduce Cas protein (Cas9) to guide RNA into cells whose DNA they want to alter

• Bioremediation: Use of organisms to remove pollutants from soil, air, or water

Chapter 28: Protists

28.1: Most eukaryoes are single celled organisms

• Protists: Eukaryote that is not an animal, plant, or fungus

  • Mostly unicellular

  • Most organisms in eukaryotic lineages are protists

• Protists can be photoautotrophs, heterotrophs, or mixotrophs

  • Mixotrophs: Combine photosynthesis and heterotophic nutrition

• Protisan diversity has origins in endosymbiosis

• Heterotrophic eukaryotes aquired a cyanobacterium that evolved into plastids through endosumbiosis, which gave rise to algae (red and green)

  • Cyanobacteria are gram negative (two cell membranes, inner cell membrane, inner plasma membrane, outer membrane)

• Secondary Endosymbiosis: Algae was ingested in food vacuoles of heterotrophic eukaryotes

28.2: Excavates include protists with modified mitochondria an protists with unique flagella

• Excavata: Clade with cytoskeleton (morphological)

• Diplomonads: Reduced mitochondria, mitosomes, without functional ETCs, instead getting energy from anaerobic biochemical pathways. Many are parasites

• Parabasalids: Reduced mitochondria, hydrogenosomes, which generate some energy anaerobically (releasing hydrogen as byproduct)

• Euglenozoans: Diverse clade that includes predatory heterotrophs, photosynthetic autotrophs, mixotrophs, and parasites. Have either a rod with a spiral or crystalline structure inside their flagella

• Kinetoplastids: Single large mitochondrion with an organized mass of DNA, a kinetoplast.

• Euglenid: Pocket at one end of the cell where one or two flagella emerge

28.3: SAR is a highly diverse group of protists defined by DNA similarities

• SAR: Subgroup of protists with stramenopiles, alveolates, and rhizarians

  • Stramenopiles: Have characteristic hairy flagellum with a shorter smooth flagellum

    • Diatoms: Type of stramenopile, unicellular algae with a unique glass like wall made of silicon dioxide embedded in an organic matrix

    • Brown Algae: Most large and complex stramenophile, multicelular, mostly marine. Most seaweeds are them

      • Holdfast: Rootlike organ which anchors the brown algae

      • Stipe: Stemlike organ which supports the leaflike bladesof brown algae

  • Alveolates: Membrane enclosed sacs (aveoli) just under the plasma membrane

    • Dinoflagellates: Group of aveolate flagellates, cells reinforced by cellulose plates

    • Apicomplexans: Aveolate parasites of animals, spread through hosts as tiny infectious cells

    • Ciliates: Large and varied group of aveolates named for use of cilia to move and feed, prottists

      • Conjugation: Sexual process in which two individuals exchange haploid micronuclei but don’t reproduce, results from genetic variation in nuclei of ciliates

  • Rhizarians: Many species of amoebas

    • Amoeba: Protist that moves and feeds by pseudopia

      • Pseudopia: Extensions that bulge from anywhere on the cell surface

      • Radiolarians: Have delicate, intricately symmetrical internal skeletons made of silica

      • Foraminiferans/Forans: Named for their porous shells (tests, which have a single piece of organic material usually hardened with calcium carbonate)

      • Cercozoans: Large group of omoeboid and flagellated protists that feed using threadlike pseudopia

28.4: Red algae and green algae are the closest relatives of plants

• Archaeplastida: Red algae, green algae, and plants

  • Green Algae: Chloroplasts very similar to chloroplasts, charophytes & chlorophytes

    • Charophytes include algae most closely related to plants

    • Chlorophytes, mostly freshwater species

28.5: Unikonts include protists that are closely related to fungi and animals

• Unikonta: Diverse subgroup of eukaryotes with animals, gunfi, and some protists

  • Amoebazoans: Many species of amoebas with love or tube shaped pseudopia

  • Opisthokonts: Diverse group of eukaryotes with animals, fungi, and several groups of protists

28.6: Protists play key roles in ecological communities

• Producers: Organisms that use energy from to convert CO₂ to organic compounds

• Consumer: Organisms that depend on producers for food by directly eating them or eating an organism that eats them

Chapter 29: Plant Diversity I — How Plants Colonized Land

29.1: Plants evolved from green algae

• Charophytes share many distinctive traits with plants and are the closest relatives of them

  • Plants & brown, red, & green algae are all multicellular, eukaryotic, photosynthetic autotrophs with cell walls made of cellulose

  • Only charophytes and plants have circular rings of protein embedded in plasma membrane which synthesize cellulose

    • In other algae it is linear

• Sporopollenin: Durable polymer layer in charophytes, prevents exposed zygotes from drying out

• Altercation of Generations: Life cycle in which multicellular forms give rise to each other in turn

  • In plants, the life cycles alternate between two generations of gametophytes and sporophytes

    • Gametophyte: Produced by mitosis of haploid gametes that fuse during fertilization (and form diploid zygotes)

    • Sporophyte: Meiosis of it produces haploid spores

      • Spores: Reproductive cells that can develop into a new haploid organism without fusing with another cell

  • Embryophytes: Multicellular dependent embryo of plats

• Walled Spores: Produced in sporangia, only in plants and not in algae

  • Sporopollenin makes the walls resistant to harsh environments

  • Sporangia: Multicellular organs that produce spores

• Apical Meristems: Localized regions of cell division at tips of roots and shoots, only in plants and not algae. Divide to allow plants’ shoots and roots to elongate

• Cuticle: Covering of epidermis, consisting of wax and other polymers

• Stomata: Specialized pores supporting photosynthesis by allowing exchange of CO₂ and O₂

• Vascular Tissue: Cells joined into tubes that transport water and nutrients, helps distinguish groups of plants (either have it or don’t)

  • Vascular Plants: Plants with vascular tissue

    • 93% of plant species

    • Seed plants are majority of the plants

    • Seedless Vascular Plants: Lycophytes and monilophytes, don’t form a clade

      • Lycophytes: Vascular club mosses and their relatives

      • Monilophytes: Vascular ferns and their relatives

  • Bryophytes: Plants without vascular tissue, don’t form a clade

• Seed: Embryo packaged with a supply of nutrients inside a protective coat. Two groups

  • Gymnosperms: Seeds not enclosed in chambers, “naked seed” plants

  • Angiosperms: All flowering plants, seeds from chambers, ~90% plants

29.2: Molasses and other nonvascular plants have life cycles dominated by gametophytes

• Three main bryophyte phyla

  • Liverworts (Named for liver shape)

  • Mosses

  • Hornworts (Named for horn shape)

  • Haploid gametophytes are the dominant stage of the life cycle

  • Usually ground hugging

• Protonema: Mass of green branched one cell thick filaments with large surface area and produces buds (in ideal conditions), which develop into a moss gametophyte. From germinating moss spores

• Rhizoids: Long, tubular single cells or filaments of cells, anchor the bryophyte gametophytes to the ground

• Gametangia: Multicellular structures that produce gametes and are covered by protective tissue, formed by gametophytes

  • Archegonia: Female gametangia

  • Antheridia: Male gametangia

• Bryophyte sporophyte has three parts

  • Foot: Absorbs nutrients from gametophyte

  • Seta: Stalk, conducts materials to sporangium

  • Capsule: Sporangium, producing spores by meiosis

    • Peristome: Ring of interlocking “teeth” in upper part of capsule, opening when dry and closing when moist so spores are dispersed gradually

• Peat: Type of moss, deposits of partially decayed organic material

1. Nonvascular and ground hugging, haploid gametophytes are dominant stage

2. Peristome teeth selective, seta elevates capsule, idk what else

3. Yes

29.3: Ferns and other seedless vascular plants were the first plants to grow tall

• Vascular plants have two types of vascular tissue

  • Xylem: Conducts most water and minerals, includes tracheids

    • Tracheids: Tube shaped cells that carry water and minerals from the roots

    • Water conducting cells of xylem are dead at functional maturity and are lignified

      • Lignin: Polymer that strengthens cell walls

  • Phloem: Has cells which are arranged into tubes that distribute sugars, amino acids, and organic products, which are alive at functional maturity

• Roots: Organs that absorb water and nutrients from soil, anchor vascular plants to the ground, instead of rhizoids

• Leaves: Primary photosynthetic organ of plants, either microphylls or megaphylls

  • Microphylls: Small, spine shaped leaves supported by single strand of vascular tissue

  • Megaphylls: Leaves with highly branched vascular system

  • Microphylls (410 million ago) before megaphylls (370 million ago)

• Sporophylls: Modified leaves that bear sporangia

  • Sori: Clusters of sporangia produced by fern sporophylls, usually on undersides of sporophylls

  • Strobili: Groups of sporophylls in cone like structures

• Homosporous: One type of sporophyll bearing one type of sporangium produces one type f spore, developing into a bisexual gametophyte, most seedless vascular plants

• Heterosporous: Two types of sporophylls (micro and mega)

  • Microspores: Develop into male gametophytes

    • Microphylls → Microsporangia → Microspores

  • Megaspores: Develop into female gametophytes

    • Megaphylls → Megasporangia → Megaspores

Chapter 30: Plant Diversity II — The Evolution of Seed Plants

30.1: Seeds and pollen grains are key adaptations for life on land

• Seed: Embryo and its food supply, surrounded by a protective coat

• Seed plants retain the megasporangium within the parent

• Integument: Layer of sporophyte tissue that envelops and protects the megasporangium

  • Gymnosperm have one, angiosperm has 2

• Pollen Grain: Male gametophyte enclosed within the pollen wall

  • Pollination: Transfer of pollen to the part of a seed plant that contains ovules

30.2: The reproductive adaptations of angiosperms include flowers and fruits

• Conifers: Cone bearing plants, most gymnosperms

• Dominance of the sporophyte generation, development of seeds from fertilized ovules, and the role of pollen in transferring sperm to ovules are key features of a typical gymnosperm lifestyle

30.3: The reproductive adaptations of angiosperms include flowers and fruits

• Flower: Unique angiosperm specialized for sexual reproduction with up to four floral organs (modified leaves)

  • Sepals: Green and enclose flower before it opens (like a rosebud)

  • Petals: Interior to the sepals, brightly colored and attract pollinators

  • Stamens: Microsporophylls, produce microspores that develop into pollen grains with male gametophytes

    • Has a filament (stalk) and anther (where pollen is produced)

  • Carpels: Megasporophylls: Produce megaspores that give rise to female gametophytes

    • Stigma: Sticky tip of carpel that recieves pollen

    • Style: Leads from stigma to the ovary

      • Ovary: The base of the carpel with one or more ovules

• Pistil: Single carpel or 2+ fused carpels

• Fruit: As seeds develop from ovules after fertilization, the ovary wall thickens and ovary matures into a fruit

• Male gametophytes have two haploid cells, a generative cell (divides into two sperm) and a tube cell (produces a pollen tube)

• Embyro Sac: Cell inside ovule of a flowering plant which becomes the female gametophyte

• After it’s released from the anther, pollen is carried to the sticky stigma at the tip of the carpel

• Cross Pollination: In angiosperms, the transfer of pollen from an anther of a flower to the stigma of a flower on another plant of the same species, which is ensured through various mechanisms

• Micropyle: Pore in the integuments of the ovule

• Double Fertilization: One fertilization event produces a zygote and the other makes a triploid cell, unique to angiosperms

• Cotyledons: Sporophyte embyro with a rudimentary root and one or two seed leaves

• Endosperm: Tissue rich in starch and other food reserves that nourish the developing embryo

• Monocots: Species with one cotyledon

• Eudicots: Clade with two seed leaves upon germination

  • Dicots: Species with two cotyledons (used until late 1990s)

• Basal Angiosperms: Lineages that diverged from other angiosperms early in the history of the group

• Magnoliids: Evolved later

30.4: Human welfare depends on seed plants

• Humans depend on seed plants for products like food, wood, and medicines

• Destruction of habitat threatens the extinction of plant species and animal species they support

Chapter 31: Fungi

31.1: Fungi are heterotrophs that feed by absorption

• Fungi are heterotrophs and absorb nutrients from environment by secreting hydrolytic enzymes into their surroundings, which break down complex molecules into smaller organic compounds that the fungi can absorb into their cells and use

  • Fungi are decomposers

• Yeasts: Multicellular filaments and single cells, most common fungal bodes

  • Often inhabit moist environments with lots of soluble nutrients such as sugars and amino acids

• Hyphae: Network of tiny filaments with tubular cell walls surrounding the plasma membrane and cytoplasm of cells (formed by bodies of multicellular fungi)

  • Chitin: Strengthens cell walls, strong but flexible polysaccharide

• Septa: Divides hyphae into cells, cross walls with pores large enough to let ribosomes, mitochondria, and nuclei to flow from cell to cell

  • Coenocytic Fungi: Fungi without septa which have a continuous cytoplasmic mass having hundreds or thousands of nuclei

• Mycelium: Interwoven mass formed by fungal hyphae, infiltrates material on which the fungus feeds and makes it efficient (high SA:V ratio)

• Arbuscules: Specialized branching hyphae used by fungi to exchange nutrients with plant hosts

  • Mycorrhizae: Mutually beneficial relationships between fungi and plant roots

• Ectomycorrhizal Fungi: Form sheaths of hyphae over the surface of a root, grow into extracellular spaces of the root cortex

• Abuscular Mycorrhizal Fungi: Extend arbuscles through root cell wall and into tubes formed by pushing inward of the root cell plasma membrane

• Spores: Haploid cells that form new mycelia after germinating

31.2: Fungi produce pores through sexual or asexual life cycles

• Pheremones: Signaling molecules released by hyphae from two mycelia

• Plasmogamy: Union of cytoplasms of two parent mycelia

  • Heterokaryon: Parts of the fused mycellium contain coexisting genetically different nuclei

  • Dikaryotic: Haploid nuclei pair off two to a cell, one from each parent

• Karyogamy: Stage after plasmogamy in the sexual cycle, haploid nuclei contributed by two parents fuse and form diploid cells

• Molds: Fungi that reproduce asexually by growing as filamentous fungi that produce haploid spores by mitosis and form visible mycelia

• Deuteromycetes: Fungi lacking sexual reproduction

31.3: The ancestor of fungi was an aquatic, single celled, flagellated protist

• Two basic lineages of fungi have flagella even if fungi don’t

• Opisthokongs: Posterior location of flagellum

• Nucleariids: Amoebas that feed on algae and bacteria, closely related to several single celled protists

31.4: Fungi have radiated into a diverse set of lineages

• Cryptomycetes and microsporidians form a sister group and are a basic fungal lineage

• Chrytids: Fungi in lakes and soil with zoospores

  • Zoospores: Flagellated spores

• Zoopagomycetes: Parasites or neutral symbionts of animals, form filamentous hyphae and reproduce asexually by producing nonflagellated spores

• Mucoromycetes: Species of fast growing molds, either parasites of plants or mutalists

• Zygosporangium: Sturdy structure where karyogamy and meiosis occur, a multinucleate structure that is first heterokaryotic with haploid nuclei from parents, then diploid nuclei after karogany

• Ascomycetes: Fungi that produce spores in saclike asci, also called sac fungi

  • Ascocarps: Fruiting bodies of ascomycetes developed in their sexual stage

• Conidia: Asexual spores produced by ascomycetes during asexual reproduction, produced externally at tips of specialized hyphae (conidiophores). May also fuse with hyphae from mycelium of a different mating type in sexual reproduction

• Basidiomycetes: Mutualists that form mycorrhizae and rusts and smuts (two destructive plant parasites)

  • Basidium: Cell where karyogamy occurs, followed by meiosis

  • Basidiocarps: Fruiting bodies produced by mycelium in response to environmental stimuli

31.5: Fungi play key roles in nutrient cycling, ecological interactions, and human welfare

• Endophytes: Fungi/bacteria that lives inside leaves or other plants without causing them harm

• Lichen: Photosynthetic microorganism and fungus symbiosis

• Lichens can asexually reproduce by fragmentation of the parent or forming soredia

  • Soredia: Small clusters of hyphae with embedded algae

• Mycosis: Infection in an animal by fungal parasite

Chapter 32: An Overview of Animal Diversity

32.1: Animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers

• Animals use collagen instead of cell walls

• Tissues: Groups of similar cells that act as a functional unit

• Cleavage: Succession of mitotic cell divisions without cell growth between them after fertilization

  • Blastula: Animals are like a hollow ball, embryonic stage

  • Gastrulation: Layers of embryonic tissues that will develop into adult body parts produced

  • Larva: Sexually immature form of an animal morphologically distinct from the adult

    • Eats different food, has different habits

    • Metamorphosis: Developmental transition from larvae to juvenile that's similar to an adult but not sexually mature

32.2: The history of animals spans more than half a billion years

• Choanoflagellates are closest living relatives of animals (morphological and genetic)

• First macroscopic animal fossils from about 560 million years ago, of Ediacaran Biota, soft bodied multicellular eukaryotes

• Cambrian Explosion 535-525 million years ago, with first arthropods, chordates, and echinoderms

  • Bilaterians: Members have two sided or bilaterally symmetric form and a complete digestive tract

    • Most of the fossils in the Cambrian Explosion were bilaterians

• In Mesozoic era (252-66 million years ago) rapid development, and the first mammals appeared

• In Cenozoic era (66 million years ago to the present) mass extinctions

1. bcad

2. The most recent common ancestor of animals is descended from the common ancestor of fungi and animals

32.3: Animals can be characterized by body plans

• Body Plan: Particular set of morphological and developmental traits that are integrated into the animal

  • Types of symmetry, radial, bilateral, or none

• Tissue organization also varies. Some lack tissues but in others the embryo is layering during gastrulation (see chapter 47)

• Diploblastic: Only have two germ layers, ectoderm and endoderm

  • Ectoderm: Germ layer covering surface of embryo

  • Endoderm: Innermost germ layer that lines the pouch that forms during gastrulation

• Triploblastic: Having three germ layers

  • Mesoderm: third germ layer in bilaterally symmetrical animals, filling the space between the ecto and endoderm

    • Coelom: Body cavity from tissue derived from mesoderm, in many triploblastic animals

      • Hemocoel: Body cavity that forms between mesoderm and endoderm containing hemolymph (fluid that helps internal transport of nutrients and waste), in triploblastic animals without coeloms

      • Some don’t have body cavities at all

• Body Cavity: Fluid or air filled space between the digestive tract (endoderm) and the outer body wall (ectoderm), in nearly all animals

  • Provide structural support, help internal transport of nutrients, gases, and wastes, kind of like blood (circulated in open system by heart)

• Animals either do protostome development or deuterostome development, distinguished by differences in cleavage, coelom formation, and blastopore

  • Blastopore: Indentation that leads to formation of the archenteron during gastrulation

    • Archenteron: An embyro’s developing digestive system, a blind pouch

    • After development of archenteron, a second opening forms at opposite end of the gastrula

32.4: Views of animal phylogeny continue to be shaped by new molecular and morphological data

1. All animals share a common ancestor

2. Sponges are the sister group to all other animals

3. Eumetazoa is a clade of animals with tissues

   1. Eumetazoans: Animals with issues, all animals except spomges amd a fw others

      1. Basal Eumetazoans have radial symmetry

4. Most animal phyla belong to Bilateria

   1. Bilaterians: Animals with bilateral symmetry and 3 prominent germ layers

5. There are three major clades of bilaterian animals, deutrostomia, lophotrochozoa, and ecdysozoa

   1. All invertebrates (animals that lack a backbone)

   2. Chordata is the only phylum that also includes vertebrates

• Lophotrochozoa: Two different features in animals in this clade

  • Lophophore: Crown of ciliated tentacles for feeding in som lophotrochozoans

  • Trochophore Larva: Developental stage of lophotrozans who don’t have lophophores

• Ecdysozoa: Secrete exoskeletons and shed old exoskeletons (ecdysis), nematodes, arthropods, and other phyla

Chapter 33: An Introduction to Invertebrates

33.1: Sponges are basal animals that lack tissues

• Sponges are filter feeders

• Spongocoel: Central cavity in sponges, pores in it are used to draw water in. Lined with flagellated choanocytes (collar cells)

• Osculum: Large opening in the sponge that water flows out of

• Mesohyl: Gelatinous region seperating two layers of cells in the sponge body

  • Both cell layers are in contact with water so they can do processes using diffusion

• Amoebocytes: Cells that move through the mesophyl of sponges and have many functions

• Most sponges are hermaphrodites (each individual is both male and female in sexual reproduction)

33.2: Cnidarians are an ancient phylum of eumetazoans

• Cnidarians are just sacs with a gastrovascular cavity (central digestive compartment) which acts as both the mouth and the anus. Two variations, polyps and medusa

  • Polyps: Cylindrical forms that adhere to the substrate by the aboral end (opposite of mouth) of their body and extend their tentacles, grabbing prey and pushing it towards the cavity

  • Medusa: Flattened version of the polyp, bell shaped body that can contract to move

• Cynidocytes: Cells unique to cnidarians on their tentacles, used in defense and prey capture. Contain cnidae, capsule like organelles that can explode outward

  • Nematocysts: Specialized cnidae with a stinging thread that can penetrate the body surface of prey

33.3: Lophotrochozoans, a clade identified by molecular data, have the widest range of body forms

Flatworms

• Flatworms have no body cavity and have flat bodies that allow diffusion across the body surface. No organs for specialized gas exchange

  • Protonephridia: Newtorks of tubules with ciliated structures (flame bulbs) that pull fluid through branched ducts opening to the outside, flatworm excretory system

• Planarians: Freshwater species that prey on smaller or dead animals and move using cilia on their central surface to glide along their secreted mucus

Rotifers & Acanthocephalans

• Alimentary Canal: Digestive tube with two openings, a mouth and an anus, in rotifers

• Parthogenesis: Asexual reproduction, females that produce more females from unfertilized eggs, in rotifers

  • Many don’t have males

• Acanthocephalans are all parasites

Ectoprocts and Brachiopods

• Ectoprocts: Colonial animals that superficially resemble clumps of moss

  • Encased in a hard exoskeleton studded with pores from where lophophores come out of

• Brachiopods: Superficially resemble clams and hinge shelled molluscs, but two halves of the branchiopod shell are dorsal and ventral instead of lateral

Molluscs

• Have a primary body cavity (hemocoel) and a reduced boelom. Have three main parts

  • Foot: Muscular and used for movement in molluscs

  • Visceral Mass: Contains most of internal organs of molluscs

  • Mantle: Fold of tissue that drapes over visceral mass and secretes a shell

    • Mantle Cavity: Mantle extension, water filled chamber which houses gills, anus, and excretory pores

• Radula: Straplike organ used to scrape up food by molluscs

• There are many different groups of molluscs

  • Chitons have oval shaped bodies and a shell composed of 8 dorsal plates. Foot acts as a suction cup and can also be used to creep slowly over the surface

  • Gastropods make up about ¾ of the molluscs, move by rippling motion of their foot or cilia, and has a shell secreted by glands at the edge of the mantle

  • Bilvalves have shells divided into two halves that are hinged and drawn together with tight adductor muscles. Gills used for feeding and gas exchange, most are suspension feeders

  • Cephalopods are predators that use tentacles to grasp prey and bite into them

• Ammonites: Shelled cephalopods, ancestor of octopuses and squids with a sedementary lifestyle

Annelids

• Segmented worms with coeloms in freshwater habitats and damp soil

• Errantians are more mobile than sedentarians

33.4: Ecdysozoans are the most species rich animal group

• Ecdysozoans molt as they grow

  • Molting: Shedding a cuticle

    • Cuticle: Tough external coat

• Nematodes/roundworms shed their old cuticle and secrete a larger one. They have an alimentary canal but no circulatory system

• Arthropods: Segmented body, hard exoskeleton, joined appedages

  • Have an open circulatory system

  • Three major lineages

    • Chelicerates: Sea spiders, horseshoe crabs, scorpions, ticks, mites, and spiders

    • Myriapods: Centipedes and millipedes

    • Pancrustaceans: Insects and lobsters, shrimp, barnacles, and other crustaceans

• Chelicerae: Pincers or fangs that are present in chelicerates

  • Eurypterids: Water scorpions, earliest chelicerates

  • Arachnids: Scorpions, spiders, ticks, mites, bulk of modern chelicerates

    • Book Lungs: Carry out gas exchange in spiders, stacked platelike structures contained in an internal chamber

• Incomplete Metamorphosis: In insect groups, the young (nymphs) resemble small adults and undergo many molts where they look more like an adult each time. Final molt, the insect reachs full size, gets wings, and is sexually mature

• Complete Metamorphosis: Larval stages specialized for eating or growwing. Larval stage is completely different from the adult stage

33.5: Echinoderms and chordates are deuterostomes

• Echinoderms: Slow moving or sessile (fixed in place) marine animals with a coelom

  • Water Vascular System: Network of hydraulic canals branching into tube feet

    • Tube Feet: Extensions that function in locomotion and feeding

Chapter 34: The Origin and Evolution of Vertebrates

34.1: Chordates have a notochord and a dorsal, hollow nerve chord

• Vertebrates: Animals with a backbone

• Chordates: Bilaterian animals

• Notochord: Longitudinal, flexible rod between the digestive tube and nerve cord. Provides skeletal support

• Pharyngeal Slits/Clefts: Grooves along the outer surface of the pharynx that develop into slips that open into the pharynx. Allow water entering the mouth the exit the body without passing through the whole digestive tract

• Lancelets/Cephalochordata: Sister group to all other living chordates, bladelike shape

• Tunicate/Urochordata: Marine invertebrates that undergo metamorphasis (reabsorb tail and notochord and nervous system, remaining organs rotate 90 degrees) after settling on a substrate

34.2: Vertebrates are chordates that have a backbone

• Vertebrates have 2+ sets of Hox genes and can duplicate genes that produce transcription factors and signaling molecules,

• Neural Crest: Collection of cells that appears along the edges of the closing neural tube of an embryo, and disperse throughoutout the embryo, giving rise to many structures (bones, neurons, and sensory capsules) unique to vertebrates

• Cyclostomes: Clade of jawless vertebrates

  • Hagfish (Myxini) and lampreys (Petromyzontida) have rudimentary vertebrae (composed of cartillage not bone)

• Conodonts: Group of slender, soft bodied vertebrates without jaws and with rudimentary internal skeletons

34.3: Gnathostomes are vertebrates that have jaws

• Gnathosomes: Jawed vertebrates

• Lateral Line System: Organs that form a row along each side of the body and are sensitive to vibrations in the surrounding water, characteristic of aquatic gnathosomes

• Placoderms: Earliest gnathosomes

• Acanthodians: Other jawed vertebrates that emerged ~same time as placoderms

• Chondrichthyans: Skeleton composed of mostly cartillage, sharks, rays, and their relatives

• Shark males use claspers on its pelvic fins to transfer sperm into the female’s reprouctive tract. many different kinds of sharks

  • Oviparous: Lay eggs in protective coats that hatch outside the mother’s body

  • Oviviviparous: Retain fertilized eggs in the oviduct

  • Viviparous: Young develop within the uterus and get nourishment from mother’s yolk sac placenta

• Cloaca: Common chamber that has a single opening to the outside where reporoductive and digestive tracts are expelled

• Osteichthyans: Ossified (bony) endoskeleton and hard matrix of calcium phosphate

  • Operculum: Bony flap covering 4/5 pairs of gills

  • Swim Bladder: Air sac in fishes used to maintain a buoyancy equal to surrounding water

• Ray Finned Fishes: Fishes named for bony rays that support their fins

• Lobe Fins: Major lineage of osteichthyans other than ray finned fishes

34.4: Tetrapods are gnathosomes that have limbs

• Tetrapods: Four feet instead of pectoral and pelvic fins

• Amphibians: Clade of cold blooded vertebrates

  • Salamanders are either entirely squatic or live on land as adults or throughout life, and the land ones walk bending side to side like early tetrapods

  • Frogs use strong hind legs to hop along terrain and have many adaptations such as camouflage or poison

  • Caecilians are legless and nearly blind and look like earthworms

34.5: Amniotes are tetrapods that have a terrestrially adapted egg

• Amniotes: Group of tetrapods whose extant members are the reptiles

  • Amniotic Egg: Four specialized membranes, amnion, chorion, yolk sac and allantois, unique to amniotes

• Reptile: Vertebrate with skin of scales, bony plates, or a combination of both

  • Ectothermic: Absorb external heat as their main source of body heat

  • Endothermic: Maintain body temperature through metabolic activity, birds

• Diapsids: Pair of holes on each side of the skull, muscles passing through the holes and attaching to the jaw. Early reptiles

  • Three lineages

    1. Turtles

    2. Lepidosaurs (tautaras, lizards, snakes, mososaurs)

    3. Archosaurs (crocodilians, pterosaurs, dinosaurs)

• Pterosaurs: First tetrapods to exhibit flapping flight

• Theropods: Bipedial carnivores

• Ratites: Flightless birds which include the ostrich, rhea, cassowary, and emu

34.6: Mammals are amniotes that have hair and produce milk

• Synapsids: Group of amniotes, early ones have no hair, swrawlking gait, and lay eggs

  • Mammals: Vertebrate with milk producing mammary glands

• Monotremes: Lay eggs, one species of platypus and four species of echidnas

• Marsupials: Young are carried in a pouch

• Eutherians: Placental mammals (placentas more complex than those of marsupials)

• Marsupials and eutherians have embryo begin devekloping in female’s reproductive tract, lining of the uterus and extraembryonic membranes form a placenta, higher metabolic rates, and nipples produce milk

  • Placenta: Structure in which nutrients diffuse into the embryo from the mother’s blood

• Opposable Thumb: Can touch ventral surface (fingerprint) of all four fingers with the ventral surface of the thumb of the same hand, unique to monkeys and apes

• Arthropoids: Monkeys and apes

34.7: Humans are mammals that have a large brain and bipedal locomotion

• Paleoanthropology: Study of human origins

• Hominins: Extinct species more closely related to humans than chimpanzees