Bio 1220 Practical II

Gametophyte (haploid)

produces gametes
stage they spend most of their time

Sporophyte (diploid)

produces spores

Hepaticophyta (Liverworts)

gametophyte dominant

Bryophyta (Mosses)

gametophyte dominant

Lycophyta (Club Mosses)

Sporophyte dominant (2n)

Psilotophyta (Whisk Fern)

Sporophyte dominant (2n)

Sphenophyta (Horsetails)

Sporophyte dominant (2n)

Pteridophyta (Ferns)

Sporophyte dominant (2n)

Gymnosperms (Seed Plants)

Sporophyte dominant (2n)

Saprophytic

obtains nutrients from dead organisms (most fungi)

Mucoromycota

Mostly soil dwelling saprophytes

Example: Bread and fruit mold, rhizopus

To sexually reproduce, they form

diploid zygospores in the

zygosporangium that will

undergo meiosis yielding haploid

zygomycete spores

Basidiomycota

Mainly saprophytic species

Reproduce sexually via the formation of

specialized club-shaped cells called a

basidium that bear basidiospores

Example: mushrooms, toadstools,

puffballs, shelf fungi, and rusts

Ascomycota

Largest fungal group

• Example: morels, molds, lichens,

truffles and single celled yeasts

• The defining feature of this group is

the ascocarp which contain the

ascus, a microscopic sexual

structure in which ascospores are

formed

Lichen

Crustose: flat

Foliose: flat with leaf like lobes

Fruticose: bushy or shrub like

Mutualistic symbiotic relationship between

cyanobacteria or green algae and a fungus

(Ascomycota)

Taphrina deformans

parasitic fungus infects peach trees causing “leaf curl disease”

sycamore trees parasitic fungus

Anthracnose fungi

Cordyceps

“mind control” ascomycota

Ectoderm

skin and nervous system

Mesoderm

muscles, connective tissue, skeleton, kidneys, circulatory and reproductive organs

Endoderm

lining of the gut and major organs derived from it

Acoelomate

Pseudocoelomate

Eucoelomate

Fertilization

egg (n) and sperm (n) unite to form a diploid zygote (2n)

• n = one set of chromosomes

• 2n = two sets of chromosomes (one from each parent)

Gametes

are produced in the gonads via meiosis

Protostomes

Develops mouth before anus as an embryo

Deuterostomes

Develops anus before mouth as an embryo

Porifera

Sponges, lack tissues, are sessile (immobile) filter feeders

Cnidaria

(jellies, coral, anemones) Radial symmetry, diploblastic (2 tissue layers) = Ectoderm and Endoderm

Possess muscle & nerve tissue = they can

move!  Have tentacles with cnidocytes (stinging cells)

that are used to capture prey

Protostome traits

bilateral symmetry, triploblastic, organ systems, cephalization 

2 lineages of protostomes

Lophotrochozoa (flatworms, earthworms, leeches, mollusks) and Ecdysozoa (Nematoda and Arthropoda) 

Platyhelminthe

Flatworms (lophotrochozoan), acoelomate, incomplete digestive system (except tapeworms)

Three groups of Platyhelminthes

Free living planarians, parasitic flukes, and parasitic tapeworms

Annelida

Segmented worms (Lophotrochozoa), Eucoelomates, complete one-way digestive tract, metameric (segmented) body

3 groups of annelids?

Terrestrial earthworms, leeches, and marine polychaetae worms

Mollusca

Mollusks (lophotrochzoans), Eucoelomate, Complete digestive tract (alimentary canal), Many possess a tongue-like structure with rows of teeth, called a radula (Except for bivalves which filter feed)

Ventral region mollusks

(underside) forms a muscular foot (arms & tentacles

in cephalopods)

Dorsal region mollusk

(top) forms into a soft mantle (folds around mantle

cavity where organs are); the mantle is surrounded by a shell (in

some organisms

4 main groups of mollusks

Chitons, gastropods (snails & slugs),bivalves (oysters & clams), cephalopods (squid & octopuses).

Incomplete metamorphosis

Juvenile stages resemble adults,

differing only in size and sexual maturity

Complete metamorphosis

Organisms undergo dramatic

transformations in form and ecology as they move from the juvenile (larval) stages to adult stages

Ecdysozoans

Grow by ecydysis (process of molting) an exoskeleton/cuticle (support and protection, but it’s not

composed of living tissue, so it does not grow and expand with

the organism, which is why they shed)

•have a three-layered cuticle

Nematoda

Nematodes or Roundworms (ecdysozoans), Pseudocoelom & complete digestive tract

Arthropod

Arthropods (ecdysozoans): includes insects, chelicerates (scorpions, spiders, ticks), myriapods (centipedes,

millipedes), and crustaceans Growth by ecdysis, Characterized by jointed limbs, Cuticle (exoskeleton) made of chitin

Tagmata

Body segments, each with a pair of appendages

4 subphyla of arthropoda

Chelicerates, myriapods, crustaceans, and insects

Chelicerates

Horseshoe crabs, spiders, ticks, mites, and scorpions, Ancient, Have 2 tagma (Cephalothorax

Abdomen)

• Have 6 pairs of appendages

• 1 pair of fanged chelicerae—feeding, defense, copulation,

movement, sensory reception

• 1 pair of pedipalps

• 4 pairs of walking legs

Myriapoda

Millipedes and centipedes, 2 tagma: head and trunk, Paired appendages per trunk segment, Centipedes are Carnivorous and often poisonous (1 pair of walking legs per segment), Millipedes are detritivores (two pairs of walking legs per segement)

Crustacea

Lobsters, crayfish, shrimp, crabs, water fleas,

isopods (woodlice), and barnacles. tagma: cephalothorax and abdomen, Unique in that they have 2 pairs of antennae

Insecta

Beetles, grasshoppers, butterflies, bees, flies,

cockroaches, ect. Most abundant and diverse 3 tagma: Head Thorax and Abdomen, 3 pairs of walking legs and Usually have 2 pairs of wings

Antennules crayfish

sensory functions, touch, smell, balance

somites crayfish

body segments

swimerettes crayfish

used for swimming, carry (and aerate) eggs in females, and help circulate water past gills

uropods crayfish

rudders and backwards swimming

telson crayfish

forms tailfan w/ uropods, has anus, backwards swimming

pyloric stomach

second part of digestive system, food is further filtered and digested

cardiac stomach

the initial, anterior part of the stomach where food is stored and mechanically ground by a gastric mill with calcified teeth

green glands

aka antennal glands, are the excretory organs of crayfish that function like kidneys to filter waste from the blood and maintain water/salt balance

gastric mill

grinding apparatus in a crayfish's stomach that uses a system of hard, ossified teeth to crush and break down food into smaller particles for digestion

Deuterostomes

triploblastic, eucoelmate, and bilaterally symmetric

Gastrulation 

cells migrate to form the three

tissue layers (ectoderm, mesoderm, and endoderm)

Neurulation

Leads to development of the nervous system

(a neural tube is formed that eventually becomes the brain

and spinal cord)

Two groups of deuterostomes

Chordates and echinoderms

Echinodermata

As adults, bodies are radially symmetrical

 Larval forms are bilaterally symmetrical

 Most have “spines” extending from their body (projections of

internal endoskeleton)—endoskeleton is not bone, it’s calcium

carbonate

 Echino = “spiny”

 Derm = “skin”

 Water-vascular system (series of internal water-filled canals

that end in structures called tube feet) used for movement

Trace the path of water through the water vascular

system

madreporite → ring canal → radial canals →

ampullae → tube feet

4 key characteristics of Chordata

1. Notochord—forms part of vertebral column

2. Dorsal hollow nerve cord—becomes brain & spinal cord

3. Pharyngeal gill slits—become openings to the outside of the body

for gas exchange (only seen during embryonic development for

terrestrial vertebrates)

4. Post-anal tail—a tail, posterior to the anus (in apes and humans, this

is only seen during embryonic development)

Urochordata

Tunicates (chordata) 

Sessile (immobile) marine organisms

 Examples: Sea squirts and salps

Cephlacordata

(chordata)

Lancelets: small, elongated “fish-like” marine

invertebrates w/ a complete digestive system that lack jaws and sense organs

Adults wriggle into the sand, leaving only its

anterior (front) end exposed

Chondrichthyes

Cartilaginous fishes (ex: sharks and rays)

 Vertebral column made of cartilage (not bone)

Notochord

forms vertebral column (surrounds spinal

cord)

3 chordate subphylas

Urochordata [invertebrates] Cephalochordata [invertebrates] Vertebrata [vertebrates]

Dorsal hollow nerve cord
Dorsal hollow nerve cord (Chordata)

forms spinal cord and brain

Pharyngeal pouches form

 Aquatic: open into gill slits = gills (gas exchange organ) Terrestrial: gill slits do not form after pharyngeal pouches form (vestigial trait—no function)

Post-anal tail

lost in some species

Families/Classes:

Chordata families/classes

• Myxinoidea

• Petromyzontoidea

• Chondrichthyes

• Actinopterygii

• Amphibia

• Reptilia

• Mammalia

Myxinoidea

hagfish, No vertebral column, has skull, slime defense mechanism—slime repels

other scavengers when a hagfish is feeding

Petromyzontoidea

Lampreys

 Skull and vertebral column

 Parasitic

Two families of jawless fish

Myxinoidea and Petromyzontoidea

Two families of jawed fish

Actinopterygii and Chondrichthyes

Actinopterygii

Ray-finned fishes

 Bone

 Operculum (bony flap that covers and

protects the gills)

Tetrapods (3)

amphibia, reptilian, mammalian