Bio211 Final

pollination

movement of male microgametophytes to female gametophyte, which is encased in the carpel

Pharyngeal slits (part of Deuterostomes)

Commonly used for feeding and gas exchange

lophophore

sessile adult structures (cilia tentacles) for filter feeding

trochophore

free swimming larvae that have ciliated bands for movement and feeding

how have flowers evolved to lure potential pollinators

offering them a reward of nectar

evolution of plants and pollinators in response to each other is an example of

coevolution

fungi are…(phylogeny)

unikonts (only have one flagellum on the posterior end)

• sister taxon to the nuclearids

When did fungi originate

~ 460 MYA

key features of fungi

• nutrition

• lifecycles

• structure

absorptive heterotrophs (all fungi)

organism absorbs small organic compounds from the environment and use them for energy and carbon

decomposers (fungi nutrition)

break down dead organic matter (animal flesh, fruit, plants) and absorb the products

parasites or pathogens (fungi nutrition)

usually absorb small organic molecules from the cells of living hosts

mutualists (fungi nutrition)

absorb small organic molecules from a living host, but also do something positive for the host (lichens)

Chitin (fungi structure)

component of fungal cell walls

• is what creates hardness and allowed for there to be evidence of fungi mya

multicellular fungi (common)

made up of many tubular filaments called hyphae. together a mass of hyphae makes up the mycelium or fungal body

septate hypha

allow nuclei to move from cell to cell (multiple tubes)

• separate each nucleus with walls (septa)

coenocytic hypha

branching filaments that make up the body of the fungus (mycelium)

• lack internal cross walls (separation) known as septa

• allows nutrients to flow freely (continuous)

asexual reproduction (fungi) (fission or budding)

mycelium breaks into several parts and grow or produce spores through sporangia or sporophores

sexual reproduction (fungi)

involve plasmogamy > karyogamy > meiosis > spores

• must be compatible haploid hyphae

plasmogamy (fungi sexual reproduction)

process of 2 haploid fungi fuse plasma membranes into 1 but nuclei are independent (NUCLI DO NOT FUSE)

heterokaryon (fungi sexual reproduction)

state of a cell containing multiple nuclei with a single cytoplasm

karyogamy (fungi sexual reproduction)

when the nuclei fuse together to form diploid cells

haustoria

hyphal structure developed by parasitic plants and fungi to penetrate host tissue and absorb nutrients

• parasitic/harmful

endophytic fungi

live in the above ground parts of the plant, they are abundant in plants in all terrestrial environments, all plants seem to have this

• produce chemicals that defend the plant from grazers, pathogens, & other env stresses

lichens (part of mutualistic fungi)

fungus + cyanobacterium/algae

• can survive in harsh environments

• sexual and asexual reproduction (soredia)

lichen reproduction

can reproduce sexually by fragmentation or by producing soredia (a few photosynthetic cells bound by fungal hyphae (asexually))

Ascomycetes and basidiomycetes (fungal taxa)

• have a septate hyphae (allows for the movement of cytoplasm and nutrients)

• have a dikaryon stage

Animals are… (phylogenetic context)

unikonts (or more specifically opisthokonts)

• the single flagellum is always located at the posterior end of the cell

• Sister taxa: choanoflagellates

Choanoflagellates

one flagellum, surrounded by a ring of microvilli that creates a water current to filter bacteria

• closest relative to animals

Cadherins

• found in protists and animals

• Explains colonies in choanoflagellates

• Allows cells to stick to other cells (stickiness!)

Hox genes

Involved in the genes encoding for the way your body forms

• control patterning of the embryo along the anterior-posterior axis

• determine the identity of body regions

Radial symmetry

Many planes of symmetry

• sessile and diploblastic

Bilateral symmetry

One plane of mirror-image halves

• more active and triploblastic

• Associated with cephalization: sensory organs

Radial cleavage

All divisions are parallel or perpendicular

• intermediate growth: all cells have the info to form the whole body/organism

Spiral cleavage

Division is off parallel

• determinate growth: cells are predetermined to become a specific body part

Gastrulation

when a single-layered blastula reorganizes into a three-layered structure called the gastrula

• gives rise to all tissues and organs

• ectoderm, mesoderm, endoderm

Ectoderm

Outer layer of tissue formed in gastrulation

mesoderm

middle layer of tissue formed in gastrulation

endoderm

inner layer of tissue in formed in gastrulation

blastopore(part of animals)

the first opening that forms during gastrulation

• determines whether the mouth or anus forms first

protosomes

mouth forms first

deuterostomes

mouth forms second

diploblastic animals

develop from two embryonic germ layers (ectoderm and endoderm)

• radial symmetry and simpler body plans

triploblastic animals

posses three embryonic germ layers (ectoderm, mesoderm. & endoderm)

• bilateral symmetry and enable complex organs and tissues

blastocoel

fluid-filled cavity that forms inside an embryo during the early blastula stage of development

body cavity classifications

how triploblastic animals are classified by how their internal organs are housed with relative to the mesoderm

• acoelomate

• pseudocoelomate

• coelomate

• determine the structure of internal spaces and organs

acoelomate

lack fluid filled cavity between gut and ectoderm

pseudocoelomate

posses a false cavity and is not lined by the mesodermal tissue

coelomates

have a fluid filled cavity and have the most complex organ system

direct development

zygote > embryo > juvenile > adult

indirect development

zygote > embryo > larva > juvenile > adult

unitary organisms

forms a single distinct individual with determinate development

• humans, birds, insects

colonial organism

forms genetically identical connected modules that function independently

• corals, sponges

how far metazoans date back

770 MYA

(represent a group of multicellular eukaryotes)

how far eumetazoans date back

680 MYA

(have true tissues)

how far bilateria dates back

670 MYA

• Consists of deuterostomia which consists of lophotrochozoas and ecdysozoa

• consists of protostomes

eumetazoans

• porifera

• ctenophora

• cnidaria

Porifera (sponges) (non bilaterian)

No symmetry, no true tissues or stomach (simplest body structure)

• have an epidermis (outer layer of cells) & an choanocytes (inner layer of cells)

• have spicules and spongin (for structure)

Mesohyl

Layer of cells between the epidermis and choanocytes in sponges

• contain spicules and spongin fibers

Eumetazoans

Have true tissues and either radial and bilateral symmetry

• when animals began to fossilize

Cnidaria (jellies)

• 2 body types polyp (sessile, living on the bottom) and medusa (mobile, swimming in the water)

• The layer in between the ectoderm(epidermis) and the endoderm(gastrodermis) is the mesoglea

Most common kind of Cnidaria

Nematocyst

(Most are predators)

Cnidaria life cycle

planula larvae stage

• alternate between mobile and sessile

2 major clades of Cnidarians

Medusazoans (medusa life cycle) and anthozoans (polyp life cycle) (corals)

Ctenophora (comb jellies)

Swim using fused cilia (ctenes) arranged in comb rows running from oral and aboral ends

• have a complete gut

3 clades of bilateria

Lophotrochoazoans (protostomes)

Ecdysozoa (protostomes)

Deuterostomes

lophotrochozoans

protostome animals that are either lophophore or trochophore

Platyhelminthes (part of lophotrochozoans)

Unitary and acoelomate

• predaorial/parasitic (trematodes)

• Flat and stretched out

Syndermata (part of lophotrochozoans)

Tiny, unitary and pseudocoelomate

• can slow down metabolism in bad conditions (cryptobiotic)

Ectoprocts (part of lophotrochozoans)

Colonial and coelomate

• use a lophophore for suspension feeding and gas exchange

Brachiopods (part of lophotrochozoans)

Unitary and coelomate

• use lophophore

Mollusca (part of lophotrochozoans)

Unitary and coelomate

• have 3 body regions

• mantle cavity and radula

Mantle cavity (part of molluscs)

A space lined by mantle continuous with the air or water outside the body; gills are held in this space

• part of molluscs

Radula (part of molluscs)

A ribbon of teeth that is used to scrape food

Mollusca body regions

• foot (crawling or swimming)

• Visceral mass (internal organs & complete gut)

• Mantle (tissue that covers the dorsal surface)

Annelids (part of lophotrochozoans)

Unitary and coelomate

• complete guts

• First taxon of segmented animals (for better movement control and catching food)

Ecdysozoans

• covered with an extracellular layers called the cuticle (used for protection and skeletal support

• Have to molt (shed) (ecdysis) the cuticle periodically

Nematodes (part of ecdysozoans)

• non segmented, cylindrical bodies

• Complete gut/digestive system

• Plant/animal parasites

Arthropods (part of ecdysozoans)

• have a pair of jointed appendages

• Hemolymph: have blood flowing through open space between tissues and organs (open circulatory system)

Insects (largest group of animals)

• head, thorax, abdomen

• Tracheae: deliver oxygen by diffusion

• Incomplete/complete metamorphosis

Incomplete metamorphosis

Molts and looks the same

Complete metamorphosis

Molts and looks different from larva stage as an adult

Deuterostomes (part of bilateria)

radial cleavage, indeterminate development (cells are not pre-destined), and coelom

Deuterostomes clades

• Echinoderms

• Hemichordates

• Chordates

• (All coelomate)

Hemichordates (worm like!)

Have a proboscis, collar, and trunk

• pharyngeal slits and softbodied

echinoderms (seastars!)

Bilateral symmetry as larvae and radial symmetry as adults

• water vascular system

• five part symmetry

Water vascular system

Water system of tubes that go into each arm that operate tube feed that control pressure for movement

• in echinoderms (seastars)

Chordate characteristics

1) a notocord

2) dorsal, hollow nerve cord

3) pharyngeal slits

4) postal-anal tail

Cephalochordates

• lancelets

• Suspension feeding

• Buried in sand and head region stays above ground

Urochordates

Have features that are only found in the larvae stage

• Tunicates (sea squirts)

Vertebrates

Have a backbone, anterior cranium (skull), and brain

• have hox genes

How jaws evolved

From gill slits and mutations over time, a hole in the skull developed behind the eyes that allowed for more muscle and stronger jaw

• anapsid > diapsid (temporal openings)

Gnathosomes characteristics

• jaws (allows for a more diverse diet)

• Enlarged forebrain (better for smell)

• Lateral line system

Tetrapods

Gnathostomes that have limbs

• Had more support and propulsion

• Neck, ribs, and fused girdles

• water > land

Amphibians

Can be on land and water (frogs and salamanders)

• inhabit damp habitats (swamps and rain forests)

• lay eggs

• thin skin