ZOOL 110 lecture exam 2 study guide

Lung

highly vascularized space within the mantle cavity of pulmonate gastropods that functions in gas exchange

Neurohypophysis

the posterior half of the pituitary gland that secretes neurohypophyseal hormones

Chondrocyte

a flagellated collar cell that lines the cavities and canals of sponges

Zooid

an individual member of a colony

Action Potential

a brief change in voltage across the cell membrane of a neuron, involved in passing an impulse along an axon

Digenetic

A parasite that has two hosts

Pharynx

the part of the digestive tract between the mouth and esophagus, involved in digestion and respiration

Flame cell

osmoregulatory cell containing a tuft of flagella, also known as a protonephridium

Dioicous

Having two separate sexes that participate in reproduction

Setae

Chitinous external structures present in polychaetes and oligochaetes

Stinging cell that defines Phylum Cnidaria

Cnidocyte

Muscle that functions to close the shell in Class Bivalvia

what electricity is used for in fishes

Hemoglobin _________ its affinity for oxygen at a low pH (more acidic conditions), and__________ its affinity for oxygen when there is a high partial pressure of O2 in surrounding tissue

Decreases, increases

White matter appears white because it is composed of _________________

Myelinated axons of neurons

Dilation of the pupils, an increased heart rate, and dilation of the bronchioles would be due to what division of what nervous system?

Sympathetic division of the autonomic nervous system

What is the function of a plasma cell

Produce antibodies

The ctenophore gut is

Complete

The cnidarian group that produces coral reefs is called

Hexacorallia

Nematodes have __________ body wall muscles

only longitudinal

oxytocin

In mammals, acts on mammary glands, induces powerful uterine contractions

Growth hormone

Stimulates growth, cell reproduction, and regeneration

adrenocorticotropic hormone

Stimulates adrenal cortex to produce aldosterone or cortisol

gonadotropins

Promote gamete production, stimulate production of sex hormones

ADH

Increases permeability of the kidney’s collecting duct

Depict the path of an action potential from the stretch receptor in your thigh muscle, through a reflex arc, to its effector

stretch receptor → afferent sensory neuron → efferent motor neuron → leg muscle (effector)

Depict the pathway of air into human lungs

nasal cavities → pharynx → trachea → bronchi → bronchioles → alveoli

Depict the pathway of water through a complex sponge (leuconoid, for example).

Ostia → incurrent canal → flagellated chamber of choanocytes → excurrent canal → osculum

What features define Nematoda? How are they different from phyla Platyhelminthes & Nemertea?

The most abundant animals, can be parasitic or free living. Pseudocoelomate

What clade are the nematodes found in? What’s ecdysis?

nematodes are in the Ecdysozoa clade. Ecdysis is the molting of the cuticle.

Why do nematodes thrash back and forth when they move?

They only have longitudinal body wall muscles and a pseudocoel that works like a hydrostatic skeleton

Do nematodes have an incomplete gut or a complete gut?

complete gut

Where do nematodes live and what do they eat?

Nematodes are found in marine, freshwater, and soil environments. They can be parasitic or free living. They eat bacteria, yeasts, fungal hyphae, algae, rotifers, tardigrades, small annelids, or other nematodes

lophophore

a horseshoe shaped feeding appendage

Trochophore

free swimming larva with a “skirt” of cilia

How do we define the clade Lophotrochozoa?

have a lophophore or a trochophore larva (except for Phylum Platyhelminthes)

What is a worm?

Bilateral elongate invertebrate without limbs

Why type of coelom does phylum Platyhelminthes have

Acoelomate (no coelom)

does phylum Platyhelminthes have a complete or incomplete gut

incomplete gut

What is the nervous system of phylum Platyhelminthes

paired anterior ganglia + longitudinal nerve cords

What are the sense organs of phylum Platyhelminthes

statocysts + ocelli

How do Platyhelminthes reproduce

Sexually through internal fertilization (penis fencing) or asexually through fragmentation

What type of cells are Platyhelminthes excretory system

flame cells

is turbellaria monophyletic

no, paraphyletic

class turbellaria belongs to what phylum

Platyhelminthes

How many species are in class turbellaria

4500

Class turbellaria body plan

Ciliated epidermis w/rhabdites, body wall muscles + muscles around pharynx

What is the only Platyhelminthes class that is not exclusively parasitic

class turbellaria

class Trematoda belongs to what phylum

Platyhelminthes

is class Trematoda monogenetic or digenetic

digenetic

Class Monogea belongs to what phylum

Platyhelminthes

Is class Monogea typically ectoparasites or endoparasites

typically ectoparasites of fish gills

Is class Monogea monogenetic or digenetic

monogenetic

Class Cestoda belongs to what phylum

Platyhelminthes

Cestoda body plan

repeating segments (proglottids) + posterior scolex to attach to the host

what kind of gut does class cestoda have

no gut

What is class cestodas nervous system

Longitudinal nerve cords

how many species are in class termatoda

11,000

how many species are in class monogea

1100

how many species are in class cestoda

4500

what kind of coelom does phylum nemertea have

Eucoelomate (true coelom)

Why clade does phylum Nemertea belong to

Kryptrochozoa

What features define Nemertea

long evertible proboscis, Most < 20 cm long, Outer circular & inner longitudinal muscles, blood-vascular system

does phylum Nemertea have a complete or incomplete gut

complete

How do nemertean worms feed?

Proboscis

Nemertean nervous system

4 lobed brain connected to paired longitudinal nerve trunks

Features shared by all cnidarians

cnidocytes, diploblastic, radial symmetry, intra and extracellular digestion,

Features shared by all ctenophores, and why they are different from cnidarians

diploblastic, bilateral symmetry, no cnidocytes, 8 comb rows

Do cnidarians have true muscles?

no, they have epitheliomuscular cells of epidermis and gastrodermis

What is the cnidarian nervous system like?

nerve net of neurons

In the life cycle of a hydrozoan (Obelia) is the polyp or medusa dominant

The Polyp is dominant

In the life cycle of a scyphozoan (Aurelia) is the polyp or medusa dominant

medusa is dominant

What is coral bleaching?

Corals expel their zooxanthellae. exacerbated by an increase in water temperature & by ocean acidification

What “first” structure is present in Ctenophora?

Anal canal

How do dinoflagellates (algae) & cnidarians work together?

The algae photosynthesize and provide the cnidarian with energy, while the cnidarian provides shelter

What phylum does class Anthozoa belong to

cnidaria

What phylum does class Hydrozoa belong to

Cnidaria

What phylum does class Scyphozoa belong to

Cnidaria

What phylum does class Cubozoa belong to

Cnidaria

What phylum does class Staurozoa belong to

Cnidaria

Class Staurozoa features

obscure cold water forms, no medusa phase

Class Cubozoa (box jellyfish) features

pedalium (base of tentacle), eyes present, velarium (subumbrella)

Class Scyphozoa (true jellyfish) features

oral arms around mouth, tentacles may be long or short

Class Hydrozoa features

most variable, similar to scyphozoans but have velum

Class Anthozoa features

largest class, includes sea anemones, stony corals

Subclass Hexacorallia features

Hard corals, major reef-building organisms, symbiotic dinoflagellate

Subclass Octocorallia features

soft corals, includes gorgonians, sea fans, whip

corals

Is Kingdom Protista monophyletic?

no, paraphyletic

What are the defining features of Phylum Porifera?

Extracellular matrix with collagen signaling molecules, blastula stage of development

How do poriferans feed?

Chondrocytes

How do sponges reproduce?

Asexually (external buds or gemmules) or sexually

How do sponges support their bodies

Spicules made of either spongin (collagen), calcium carbonate, or silica

How many classes of sponges are there?

4: Hexactinellida, Demospongiae, Calcarea, and Homoscleromorpha

Why are placozoans considered animals?

genetic sequencing

Features of Trichoplax adherens

marine, small (2-3 mm), flat sheet of cells

What is the HAM?

hypothetical ancestral mollusc

What features are considered synapomorphies for molluscs?

Head-foot, shell, radula, mantle and mantle cavity

Radula

rasping, protrusible tongue-like organ

Mantle

folds of skin (outgrowths of the body wall)

The three types of larvae in molluscs

trochophore, veliger, and glochidium

Class Polyplacophora in is what phylum

Mollusca