Biology 103 Final Exam- McMullen

Are protists a monophyletic group?

No, they are paraphyletic

Protists are ____________

Eukaryotes

Are protists multicellular or unicellular?

Both

Are protists motile or nonmotile?

Both

Are protists aquatic or terrestrial?

Both

Are protists autotrophs or heterotrophs?

Both (algae is only autotroph)

What is carageenin in brown algae?

It thickens liquids in the algae

What are some examples of protists?

euglena, amoeba, diatoms, dinoflagellates, algae, protozoa, slime molds, water molds

Which protist causes "toxic red tides"?

Dinoflagellates

Which protist is not unicellular OR multicellular?

Slime Molds

Which protist is single celled and has silica in the cell wall?

Diatoms

What is the ecological importance of protists?

Carbon fixation- the marine photosynthetic protists are responsible for removing over 50% of carbon

Are protists at the bottom or the top of the aquatic ecosystem?

Bottom

Plasmopara viticola

Downy mildew of grape

Millardet

Professor who prepared the first foliar fungicide for plant disease within the mildew of the grapes

Phytophthora

Destructive parasitic fungi causing brown rot in plants, caused havoc during the potato famine (over 800,000 people starved)

Reproduction in Protists

Some protists reproduce asexually by mitosis and some undergo conjuction, other protists have a life cycle that combines asexual and sexual reproduction (which also means an alteration of diploid/haploid dominant generations)

What type of meiosis is in haploid dominant life cycles?

Zygotic meiosis (zygote is the only diploid cell)

What type of meiosis is in diploid dominant life cycles?

Gametic meiosis (gametes are the only haploid cells)- eggs and sperm

What are the 3 gamete types?

Isogamy

Anisogamy

Oogamy

What kind of meiosis produces haploid spores?

Sporic meiosis

What are characteristics of animals?

Multicellular

Heterotrophic (and ingest food)

No cell walls

Multicellular organism that ingests food is a unique combination-not impossible, but rare

What do zoologists agree about animals?

They arose from single celled protists

What is the colonial hypothesis?

Ancestors of animals were colonial, flagellated protists that evolved specialization and dependence upon one another until they became multicellular

What are choanoflagellates?

A group of free-living unicellular and colonial flagellate eukaryotes considered to be the closest living relatives of the animals

What type of digestion do choanoflagellates use?

INTRAcellular digestion

______ is flagellated in many animals.

Sperm

What phylum are sponges in?

Phylum Porifera

Are sponges symmetrical?

No, they are asymmetrical

Sponges are mostly _____.

Marine, but some are freshwater

Sponges are ______cellular.

Multi

What evidence is there today that supports the colonial hypothesis?

Choanoflagellates form colonies in present day (so it makes sense they would back then too).

If protists were not flagellated then flagella would have had to evolve many times (which goes against the principle of parsimony)

What is the gelatinous matrix comprised of?

Choanocytes and Amoebocytes

Choanocytes

Feeding cells (interior)

Amoebocytes

Shaping and functioning

What do spicules do? Where are they located?

Located in the amoebocytes, they give substance and a hard rough texture

What type of feeders are sponges?

Filter feeders with intracellular digestion

What do you call it when food particles are taken in and then brojen down with digestive enzymes? (Seen in sponges)

Phagocytosis

Is the animal life cycle haploid or diploid dominant?

Diploid dominant (h=23, d=46)

The diploid cells of an animal differentiate into which two lines?

Germ (makes sperm and egg) and somatic (all cells besides the reproductive cells)- somatic uses mitosis only

Dioecious Female

Egg only

Dioecious Male

Sperm only

Monoecious (hermaphroditic)

Both male and female reproductive systems in one individual

What are some dioecious species?

MOST jellyfish/Cnidaria

MOST roundworms/Nematoda

SOME squids/Mollusca

Insects/Arthopoda

Sea stars/Echinodermata

Vertebrates/Chordata

What are some monoecious species?

Sponges/Porifera

Flatworms/Platyhelminthes

SOME earthworms/Annelida

MANY clams/Mollusca

Monoecious species can _________

Self fertilize or cross-fertilize

Sponges are _______

Monoecious.

Sperm is released into the water (makes crossing possible)

Same individual that makes the eggs also retains them

Sperm enters the sponge to unite with the eggs

External Fertilization

Lots of zygotes (sperm and egg cells) are shed

Usually aquatic to keep the gametes from drying out

Fertilization occurs in the environment (not inside the female)

Reproductive structures are less sophisticated

Timing is crucial so the gametes meet (pheromonal control)

Internal Fertilization

Eggs are retained by the female

Aquatic or terrestrial

Fewer zygotes (protected within the female)

More sophisticated reproductive structures to insert/receive sperm

Timing is still crucial (hormones)

Direct Development

Egg to juvenile with no larvae stage (immature is just a smaller version of mature version)

Ex: Humans

Indirect Development

Egg to larvae stage, to adult (larvae undergoes radical transformation to obtain the adult form)

Ex: frogs, butterflies

All animals (EXCLUDING SPONGES)

Has tissues

Shows symmetry

EXTRAcellular digestion

Nerves

Examples of the Phylum Cnidaria

Hydrozoans, jellyfish, sea anemones, corals

What type of digestive system do cnidarians have?

Incomplete

What is a complete digestive system vs an incomplete digestive system?

Complete- 2 openings for mouth and anus

Incomplete- 1 opening, same place for mouth and anus

In cnidarians, what is the polyp stage?

When they are stuck in the substrate

In cnidarians, what is the medusa stage?

When they are free floating

Cnidarians are _______

Diploblastic (2 tissue types)

What type of symmetry do cnidarians have?

radial

What type of digestion do cnidarians have?

Extracellular

Where does extracellular digestion occur in cnidarians?

Gastro

What type of muscles do cnidarians have?

Rudimentary

Cnidarians have no ________ system (brain, spinal cord), instead they have _________

Central nervous system

Ocelli (light)

Statocysts (gravity/equillibrium)

Chemoreceptors (chemical)

Mechanoreceptors (physical/touch)

Asexual reproduction in jellyfish

Budding- Makes medusae

Sexual reproduction in jellyfish

Dioscious medusa- makes the polyps

What type of fertilization occurs in jellyfish?

External

What type of development do jellyfish exhibit?

Indirect- planula larvae is formed

Descriptions of Bilaterians

animals with bilateral symmetry

complete digestive tract

cephalization

body cavity (coeclom)

TRIpoblastic (3 tissue types, true muscle tissue)

Cephalization

concentration of sense organs and nerve cells at the front of an animal's body and locomotion structures are located at the back of the body

Ectoderm

Epidermis and nervous system

Endoderm

Digestive system

Coeloms

body cavities, leave room for our body organs and allow them to be cushioned by our fluid-filled bodies

What are the advantages of coeloms?

More spaces for organs

Better transport of molecules

Hydrostatic skeleton for movement

What makes protostomes and deuterostomes different embryotically?

Cleavage patters

Gastrulation

Coelom formation

What type of cleavage patterns do protostomes have?

What type do deuterostomes have?

Spiral- Protostomes

Radial- Deuterostomes

Gastrulation forms what 3 embryotic tissues?

Ectoderm, mesoderm, endoderm

What is different in terms of gastrulation in protostomes vs deuterostomes?

The fate of the blastopore

Coelom formation in protostomes

Schizocoely- Solid mesoderm splits

Coelom formation in deuterostomes?

Enterocoely- mesoderm pockets pinch off the gut

Are Ecdysozoans protostomes or deuterostomes?

protostomes

Ecdysozoa descriptions

Cuticle

Direct development (no larvae)

Growth by MOLTING (cuticle does not grow)

Anthropoda and Nematoda belong in the _______ category

Ecdysozoa

What are the functions of the cuticle in ecdysozoas?

Exoskeleton for support and movement

Restricts water loss

Protection for internal tissus

Protection against bacteria, viruses, and protists

(In parasitic ecysozoans, it protects them from the digestive enzymes of their host)

What does ecdysis mean?

Molting

What phylum includes segmented bodies that evolved more than once?

Phylum Arthopoda

What are some examples in the phylum arthopoda?

Spiders and scorpions

Crustaceans

Centipedes and Millipedes

Insects

What are some advantages of segmentation in chordata?

Duplication- in annelids, each segment develops a complete set of organs so damage to one segment is not fatal to the entire organism

Locomotion- individual segments move independently, which adds flexibility and complex movements

Heartworms and Hookworms are a part of what phylum?

Nematoda (parasitic)

Members in the Nematoda phylum have __________ bodies

unsegmented

Where are members of the Nematoda phylum abundant and widespread?

The soil

Trochopore larva is most produced by which 2?

Mollusca and Annelida

What is the name of the monophyletic group mollusca and annelida belong to?

Lophotrochozoa

Phylum Annelida

Segmented internally and externally

Coelom functions as a hydrostatic skeleton

Complete digestive tract

Ex: Earthworms

Phylum Mollusca

Thick epidermal mantle (secretes a shell in shelled mollusks)

Large, well defined muscular foot (can become tentacles)

Gastropoda (Mollusca)

snails and slugs

Bivalvia (Mollusca)

clams, mussels, scallops, oysters

Cephalopoda (Mollusca)

squid, nautilus, octopuses

Descriptions of the Phylum Platyhelminther

Habitats include marine, freshwater, and moist terrestrial areas

No specific respiratory organs

Incomplete digestive tract

Members are acoelomates (lost their coelom)

Some are free living and others are parasitic

No circulatory organs

What is the common name for platyhelminther phylum?

Flatworms

What two phylums make up deuterostomes?

Echinodermata and Chordata