bio exam 2

Fungi are closely related to plants or animals

What lineage

animals

opisthokonta

How would you define a fungus in order to distinguish it from a plant or animal

fungi have chitin cell walls, no cholorplasts, and digest food through secreting enzymes of mycelium

How are fungi important to other organisms, including humans?

fungi are used in the medical industry (penicillin, anti fungal agents, athletes foot, yeast infection, ringworm), used to enhance quality and reproduction, releases gas into the atmosphere (nitrogen and oxygen), organic matter for decomposing, and food (truffles, yeast)

Athough a mushroom or a spot of bread mold may appear to be a solid mass, how are such fungi organized at the microscopic level? What is the \n advantage of such an architecture

fungi consist of a network of mycelium and a pattern on spores called sporangium

What carbohydrate makes up the cell walls of fungi

chitin

Describe the general mechanism by which fungi obtain their nutrients.

fungi absorb food by secreting an enzyme using that enzyme to digest food and absorbs through their hyphae walls

What is a saprophyte

a living organism that lives and feeds off of dead or decaying organism

What are two enzymes possessed by some fungi that enable them to digest wood

ligninases and ligninolytic

Contrast between septate and coenocytic hyphae

septet hyphae have walls between the cells separating the hyphae, coenocytic hyphae don’t have walls

What are lichens? How does each member of this symbiotic \n association benefit

lichen are mutualistic symbiosis fungi that provide food and habitat for animals and protect trees and rocks from harsh conditions

What are mycorrhizae, and what is their ecological significance? How does each member of this symbiotic association benefit?

mycorrhizae are a symbiotic association between plants and roots and fungi, they enhance nutrient and water intake by plants by exploiting larger volume of soil than roots

What two general forms of reproduction occur in fungi

sexual and asexual

What type of structure (sexual or asexual) is the mushroom to a basidiomycete?

sexual through basidia

Understand the generalized life cycle of a fungus

haploid phase -→ nuclear fission -→ diploid phase

Which ploidy level, haploid or diploid, predominates in the life cycle of a fungus

haploid phase

Define “heterokaryotic”. How does a heterokaryotic stage form in a fungus

heterokaryotic is the stage after plasmogamy when a cell contains two genetically different nuclei

Describe the sexual spore-producing structure found in the zygomycota

sexually reproduced through two morphologically similar tangia of opposite mating types

What is the only fungal phylum to produce flagellated gametes and spores?

chytridiomycota because they are unicellular

What fungal phylum is the main fungus in mycorriza

chytridiomycota

What fungal phylum is responsible for a decline in amphibian populations

chytridiomycota

What fungal phylum forms most mycorrhizae

phylum glomeromycota and phylum mycorrhizae

Describe the sexual spore-producing structure found in the ascomycota

sexually reproduced when thousands of ascidians fill a ascocarp, the diploid nucleus turns to haploid through meiosis

Describe the sexual spore-producing structure found in the basidiomycota

sexually reproduce through basidia

What key traits are shared by all animal

all are heterotrophic, all are motile at some point of their life, all (except sponges) have nerve chords and muscles

What are metazoan

all animals

What are Eumetazoans

all animals w/ tissue

Discuss the data that support the origin of animals: when did they arise, according to chemical evidence, DNA analyses, and other molecular dat

animals arose 770mya, 710myo seidment contain chemical evidence of steroids (same found in modern day sponges), DNA analysis estimate sponges evolve 700-710mya, molecular data supports that a common ancestor of animal lived 770mya

When in the fossil record do animals first appear

560 mya

Ediacaran biota

the first animal fossil seen and date back to 560mya

What protists are most closely related to animals? What are three pieces of evidence supporting this relationship

protisits are closely related to animals are choanoflagellates. 3 pieces of evidence morphologically choanoflagellates cells and collar cells in sponges are similar, similar collar cells have been found in other animals but never non choanoflagellates, protists, plants, or fungi, DNA sequence indicates choanoflagellates and animals are sister groups

basal phylum

phylum that diverged early from the root of the tree (ponifers)

What are germ layers? What types of tissues and organs develop from each of the embryonic germ layers

embryonic tissues layers in development (ectoderm, endoderm, and mesoderm)

What animal groups are considered diploblastic

jellyfish, coral etc

How do diploblasts differ from triploblastic

frogs, humans, worms

Among animals, what types of body symmetry can be distinguished, and how do these differ from \n each other

radical symmetry and bilateral symmetry

Which animal phylum that we’ve discussed exhibits radial symmetry

sponges

What is a coelom? What are some functions of a coelom

fluid filled body cavity between inner and outer tube; allows support nd movement of larger bodies that lack limbs, provides cavity for organ development and allows circulation of nutrients, gases and waste

acoelomates

no body cavity

pseudocoelomates

body cavity only partially lined with mesoderm

What are two main factors that likely drove the diversification of animals in the Cambrian period? \n Explain how these factors could lead to diversification

increase O2 levels at the beginning of Cambrian period, allowed animals w/ larger bodies, higher metabolism rates to drive, could make more ATP via aerobic metabolism; evolution of predation

what are the functions of choanocytes and amoebocytes in a sponge

drive water flow, engulfs food

spicules

provide support

What are the two body forms seen in a cnidarian life cycle

polyps (sessile, asexually), and medusa (motile, sexual)

What synapomorphy unites the cnidarians? What is a function of this characteristic

cnidocyte which specializes in used to capuring prey (stinger);posses gastrovascular cavity (digestive opening)

What are the main members of the cnidarians

corals, hydras, jellyfish, sea anemone etc

What organisms live symbiotically in coral tissues? How does each member of this symbiosis \n benefit

dinoflagellates called zooxanthellae

coral bleaching

the loss of zooxanthellae from coral polyps, could cause polyp to die

endoderm

gives rise to digestive system

ectoderm

gives rise to skin and nervous system

mesoderm

gives rise to muscles, bones and most organs

radical symmetry

multiple planes of symmetry often sessile and planktonic animals

bilateral symmetry

single plane symmetry sponges lack symmetry

The terms ‘Protostome” and “deuterostome” were initially used to describe a particular \n developmental characteristic/pattern

they are used to describe and classify and animal (clade)

Many bilaterian phyla first appear in the fossil recording during the ___

Cambrian period

the three bilaterian clade

lophotoochoaza, ecdysozoa, and deuterostomia

some adaptations that made the transition to land possible in some animal

keep respiratory gas exchange membranes moist (lungs, gills,skin), need to avoid desiccation of body ( live in moist soils/habitats), gills /lungs located in body In some, evolution of any layer (innsects)

modular body plan

small set of elements are used to create body; can be arranged in different ways resulting in diversity

What are the two major clades of protostomes? What are the key phyla in each?

lophotorochozoa ( grow incrementally no molting) and ecydsozoa (need to molt; shed exoskeltonor cuticle

Whichprotostome phyla exhibit segmentation

ecydsozoa

lophophore

ciliated feeding structure “tuft bearer”

trochophore

ciliated larvae stage “wheel-bearer”

What are the common names of members of platyhelminthes

flatworms (freeliving), flukes (parasite), tapeeworms(paraste)

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What are the common names of members of annelida?

earthworms (freeliving), marine annelid (parasite), leeches (parasite)

What are the 3 body regions of a mollusk? Which secretes the shell

foot, visceral mass, and mantel (secrete shell)

What are the 3 major classes of mollusks? What common organisms are found in each? Which \n class possess a closed circulatory system, as opposed to other molluscs that have an open systysem

bivalvia (clams, mussels, scallops, chamber nautilus, oyster; open circulatory), Gastropoda (snails and slugs; open circulatory), cestropda (squids, octopuses, chamber nautilus, and cuttlefish; closed circulatory)

What characteristic (synapomorphy) unites all animals within the Ecdysoz

posses cuticles that are periodically molted

What are two morphological characteristics that tardigrades and velvet worms share \n with the arthropods? Which phylum, the Tardigrades or Onychophorans, is a sister taxon to \n Arthropods?

\

they have segmented bodies and limbs;Onychophorans

What is a nematode? What is an importance of free-living soil dwelling nematodes? How do some \n nematodes impact human health? Why do they swim in a typical “S” or whiplike fashion?

unsegmented round worms; they important in the breakdown of and recycling of organic matter as well as genetic development; they only have longitude muscles

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\n What are 2 advantages gained by the presence of an exoskeleton? How do the exoskeletons of crustaceans differ from those of other arthropods?

allows for muscle attachment and provides protection form predation and desiccation

Which phylum is the most successful phylum in terms of diversity

arthropod

What anatomical/body plan characteristic do arthropods share with annelids?

segmented bodies

What are the 3 major subphyla of arthropods? What are the classes found within each, and what \n types of organisms (common names) are found in each group

myriapod (centipede and millipede), chelicerate (arachnids) and pancrustea (crustaceans)

How do centipedes differ from millipedes? What are the class names for these organisms?

centipedes (carnivore, anterior apendages modified into venomous fangs/claws), 2 legs per segment.

millipedes (detrivores, 4 legs per segment)

What habitats do crustaceans occupy? What structural characteristics distinguish crustaceans \n from other arthropods?

fresh water and marine water, 2 pairs of antennae, branched appendages, 2 magmata (cephalothorax and abdomen)

What are the most prominent anatomical features of insects?

3 magmata (head, thorax, abdomen), 1 pair antennae, 1 pair mandible, 3 pairs of legs, 1-2 pair of wings

What are the 2 major types of metamorphoses employed by insects and how do they differ?

hemimetabolous and homometabolous

Which protostomes are acoelomates? Which are pseudocoelomates? Which are coelomates?

acoelomates: playthelmenthines

pseudocoelomates: nematodes

coelomates: annelids, mollusks, anthropoids, chordata)

How would you explain the difference between a spider and an insect

spider have 8 legs insects have 6

hemimetabolous

incomplete metamorphosis (egg-→nymph-→ adult)

homometabolous

complete metamorphosis (egg-→larvae--.pulp-→ adult)

What are the two major phyla of deuterostomes? Are all members of the phylum Chordata \n also vertebrates

Phylum Echinodermata and phylum chordata

What anatomical feature, also a synapomorphy, accounts for the phylum name \n “Echinodermata?” (i.e. why are they called Echinoderms?) What is another synapomorphy uniting echinoderms

spiny endoskeleton and water vascular system

What are some functions of the water vascular system in echinoderms

series of branching fluid-filled tubes and chamber; fluid is often sea water, allows movement, gas exchange, and feeding

What are three other examples of echinoderms

sea stars, sea urchin, and sea dollars

Define “keystone species.” What is an example of a keystone species, as presented in class? \n

a species that is crucial to survival of other species in an ecosystem, example sea star

What 4 characteristics are shared by all members of the phylum Chordata at some point in \n their development

during some parts of they lives all chordata have dosas hollow nerve cords, notorchord, post anal tail, and pharyngeal Gil slits

What is the function of the notochord in the invertebrate chordates? What happens to the \n notochord in a vertebrat

supportive rod below nerve chord, it is the direct development of the vertebrae or spinal cord

What are the three chordate subphyla? What are main characteristics of tunicates and \n lancelets

urochordata,cephelochordata, and vertabata

What are two synapomorphies uniting the vertebrate

vertebrae (spinal cord) and cranium (skull)

What are the 2 members (common names) of the subphylum Vertebrata that lack jaws? How \n do these 2 groups compare in their method of feedin

hagfish and lamprey, they feed by attaching and fluid feed

What are key events that led to diversification of the vertebrates

evolution of jaws, evolution of limbs, and modification in reproduction

How can the evolution of \n jaws lead to diversification

it led to fishes being able to bite and improve the ability to catch prey

What is a tetrapod? What animal classes are tetrapods

animals with four limbs, (amphibians, mammals, and reptiles)

What is the link between lobe-finned fishes and tetrapods?

the link between lobe-finned fishes and tetrapods are Tikaalik, which are the first animal to posses both characteristics of lobe-finned fishes and tetrapods

Which animals classes are amniotes? How doe being an amniote allow an animal to be more \n adapted for living on land? Why are animals that have a placenta still classified as amniotes, if \n they do not lay an amniotic egg?

reptiles and mammals, humans are considered amniotes because we posses amnion

What is different about the skeleton of Chondrichthyes compared to that of other vertebrates? \n

Chondrichthyes are made out of cartilage

amnion

contains embryo

yolk sac

contains nutrients

allantois

allows waste

chino

allows gas exchange