Evo/Bio Test 3 Part 1

Like fungi, animals are multicellular heterotrophs. How do they feed?

Either by eating other living organisms or by eating nonliving organic material.

what two types of specialized cells do only animals have?

Muscle cells and nerve cells

most animals reproduce________, and the_________stage dominates the life style.

sexually; diploid

zygote

a small flagellated sperm fertilizes a larger, non-motile egg, forming a diploid _____.

blastula

cleavage leads to the formation of a multicellular stage called a _____, which in many animals takes the form of a hollow ball

gastrula

during gastrulation layers of embryonic tissues that will develop into adult body parts are produced. The resulting developmental stage is called a ______.

blastopore

the opening of the archenteron in the gastrula that develops into the mouth in protostomes and the anus in deuterostomes

cleavage

the zygote of an animal undergoes _____ - a secession of mitotic cell division which results in the formation of the blastula stage.

gastrulation

a rearrangement of the embryo in which one end of the embryo folds inward, expands, and eventually fills the blastocoel; producing layers of embryonic tissues.

metamorphosis

a resurgence of development that transforms the animal into an adult.

All eukaryotes have sets of regulatory genes containing common sets of DNA sequences called homeoboxes. What are the unique homeobox genes of animals called?

Hox genes

Which animal group lacks symmetry?

Sponges

Two types of symmetry are seen in all other animal groups. Name and describe them.

Radial Symmetry - the parts of a radial animal, such as a sea anemone, radiate from the center.
Bilateral Symmetry - a bilateral animal, such as a lobster, has a left side and a right side.

Radial symmetry

the parts radiate from the center. ex: sea anemone

Bilateral symmetry

has a left side and a right side. ex: lobster, humans

What is the symmetry of a jellyfish?
Of a worm?
Of a dog?

radial
bilateral
bilateral

anterior

referring to the head end of a bilaterally symmetrical animal.

posterior

pertaining to the rear, or tail end, of a bilaterally symmetrical animal.

dorsal

pertaining to the back (top) of a bilaterally symmetrical animal.

ventral

pertaining to the underside, or bottom, of a bilaterally symmetrical animal.

with bilateral symmetry, major sensory structures and the "brain" are concentrated in the head region. What is this called?

Cephalization

Cephalization

an evolutionary trend toward the concentration of sensory equipment on the anterior end of the body.

Many animals with radial symmetry are sessile. What does this mean?

planktonic - drifting or weakly swimming.

how is radial symmetry an advantage to sessile or planktonic animals?

helps them meet the environment equally well from all sides.

endoderm

The innermost of the three primary germ layers in the animal embryos; lines the archenteron and gives rise to the liver , pancreas, lungs, and lining of the digestive tract.

ectoderm

The outermost of the three primary germ layers in animal embryos; gives rise to the outer covering and, in some phyla, the nervous system, inner ear, and lens of the eye.

mesoderm

The middle primary germ layer of an early embryo that develops into the notochord, the lining of the coelom, muscles, skeleton, gonads, kidneys, and most of the circulatory system.

which animal groups have only two tissue layers and are said to be diploblastic?

cnidarians and ctenophara (comb jellies)

What is a coelom?

a fluid-filled space separating the digestive tract from the outer body wall surrounded by mesoderm on both sides.

what do we call the animal groups that have a body cavity with mesoderm on only one side?

psuedocoelomates

What are the animal groups called that have no body cavity?

acoelomates

what are three functions of the body cavity?

its fluid cushions the suspended organs, helps prevent internal injury. In soft bodied coelomates the coelom contains non compressible fluid that acts like a skeleton against which mussels can work. also enables internal organs to grow and move independen

protostome development

In animals, a developmental mode distinguished by the development of the mouth from the blastopore; often also characterized by schizocoelous development of the body cavity and by spiral cleavage.

deuterostome development

In animals, a developmental mode distinguished by the development of the anus from the blastopore; often also characterized by entercoelous development of the body cavity and by radial cleavage.

what forms the mouth in a deuterostome?

the mouth forms from a secondary opening.

if each cell in the early embryo has the capacity to develop into a complex embryo, what is this type of cleavage called?

most animals with deuterstome development are further characterized by indeterminate cleavage - meaning that each cell produced by early cleavage division retains the capacity to develop into a complete embryo.

what type of cleavage is it id the developmental fate of each embryonic cell is rigidly "determined" very early?

the determinate cleavage of protostome development pattern rigidly "determines" the fate of each embryonic cell very early.

you will notice that most animals have spiral and_______cleavage or radial and _________cleavage.

determinate; indeterminate

Lack symmetry and true tissues?

porifera (sponges)

show radial symmetry and are diploblastic?

cnidaria (Sea anemone. Hydras Corals Sea jellies)

have three tissue layers, but lack a body cavity?

platyhelminthes (flatworms)

show bilateral symmetry and have a pseudocoelom?

nematoda (round worms)

have a true coelom and are protostomes?

annelida (segmented worms), anthropodia (insects, arachnids, and crustaceans)

have true coelom and are deuterostomes?

echinodermata, chordata

are your closest relatives?

echinodermata (starfish, sea urchins, sand dollars, and sea cucumbers)

what is the feeding method of a sponge?

suspension feeders: they capture food particles suspended in the water that passes though their body.

most sponges are hermaphrodites. what does this mean?

that individuals function as both male and female in sexual reproduction by producing sperm and eggs.

cnidarians are diploblastic and have radial symmetry. explain what this means

the body wall of a cnidarian has two layers of cell: a layer of epidermis and an inner layer of gastrodermis. Digestion begins in the gastrovacular cavity and is completed inside food vacuoles in the gastrodermal cells. flagella on the gastrodermal cells

what is the body form a jellyfish called?

medusa

what are nematocysts, and how do they help a cnidarian obtain its food?

a stinging capsule-like organelle in a cnidocyte.

what is the nervous system of a cnidarian? Do they have a brain?

cnidarians have no brains but they do have a non centralized nerve net.

what is the "skeleton" of a cnidarian?

cnidarians have hydrostatic skeletons

hydrostatic skeleton

a skeletal system composed of fluid held under pressure in a closed body compartment; the main skeleton of most cnidarians, flatworms, nematodes, and annelids.

what specialized organ do flatworms have to manage water balance and nitrogenous wastes?

flatworms have no specialized organs for gas exchange or circulation and their relatively simple excretory apparatus functions mainly to maintain osmotic balance in their surroundings.

Turbellaria

most marine, some freshwater, a few terrestrial; predators and scavengers; body surface ciliated. ex: planarians, mostly free-living flatworms.

termatoda

parasites, almost always of vertebrate, two suckers attach to host; most life cycles include intermediate host. ex: flukes (platyhelminthes)

cestoda

parasites of vertebrates, colex attaches to host; proglottids produce eggs and break off after fertilization; no head or digestive system; life cycle with one or more hosts. ex: tapeworms

Planaria:
where so wastes leave? the digestive system is sometimes called two-way. why?

undigested wastes are ejected through the mouth. Because everything goes in or our through the mouth.

How do tapeworms attach to the gut of the host? this is another worm with a complex life cycle. How might you get a tapeworm?

in tapeworms, the anterior is armed with suckers and hooks that look the worm to the intestinal lining of the host. when humans eat uncooked meat contaminated with cysts, the tapeworm larvae develop into mature adults within the human.

tapeworms have no digestive system. why not?

tapeworms lack gastrovascular cavity; they absorb nutrients released by digestion in the host's intestines.

Mollusca:
muscular foot

used for movement

mollusca:
visceral mass

one of the three main parts of a mollusk, containing most of the intestinal organs

mollusca:
mantle

a fold of tissue that drapes over the visceral mass and secretes a shell.

mollusca:
radula

organ used for feeding used by many molluscs

Oligochaeta

reduced head, no paraphodia but chaetae present. Ex: fresh water marine terrestrial segmented worms.

polychaeta

Well-developed head, each segment usually has parapodia with chaetae, tube dwelling and free living. Ex: mostly marine segmented worms

hirudinea

flattened body with reduced coelome segmentation; chaetae absent; suckers at anterior and posterior ends; parasites and scavengers. Ex: leeches

eathworm:
clitellum

organ that secrets a mucus cocoon

earthworm:
metanephridia

a type of excretory tubule with internal opening called nephrostomes that collect body fluids and external opening called nephridlopores

chaetae

bristles that provide traction for burring.

what makes up the body covering of a nematode?

the body is covered by tough coat called a cuticle

trichinella - how does it work/life cycle

this worm causes trichinosis. humans acquire this nematode by eating under cooked infected pore or other meats with juvenile worms in the mussel tissue. within the human intestines, the juveniles develop into sexually mature adults. females burrow into th

what does the phylum name Arthropodia mean?

jointed feet

what is the body covering of the ecdysozoan? what molecule is it made of?

the body is completely covered by the cuticle which is made of chitin

what is the shedding process called?

molting or ecolysis

describe the circulatory system of arthropods.

arthropods have an open circulatory system in which homolyph is propelled by a heart through short anterior and then into space, sinuses, surrounding the tissue and organs through pores that are usually equipped with valves

how many legs do arachnids have?

8

what are three examples of arachnids?

scorpions, mites, and ticks

for the class insecta, hoe many legs do all members have?

6

what are the 3 body regions of insects?

1) head 2) thorax 3) abdomen

incomplete metamorphosis

a type of development in certain insects where the young resemble adults but are similar and have different body proportions

complete metamorphosis

the transformation of a larva into an adult that looks different and often function differently in its environment, in the larva.

how many pairs of appendages does a lobster have?

a lobster has 19 pairs of appendages.

as adults, many echinoderms appear to have radial symmetry, but their larval stage is bilateral. what other interesting facts did you find out about this group

echinoderms have water vascular systems
the internal and external parts of most echinoderms radiate from the center.