Download Unit 7

Macias,
Rachel
2/18/03
Period 3
Chapter 25: Tracing Phylogeny: Macroevolution, the Fossil Record, and Systematics
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List the major taxonomic categories from the most to least inclusive.
Kingdom, phylum, class, order, family genus, and species.
2. Explain why it is important when constructing a phylogeny to distinguish between homologous and
analogous character traits.
In constructing phylogeny, this is important because only by comparing species’ homologous structures can
their past evolutionary relationship be determined.
3. Distinguish between homologous and analogous structures.
A homologous structure is a likeness seen between two animals who may have shared ancestry. An
analogous structure is one that is similar only as a result of convergent evolution (having similar habitats)
and not shared ancestry.
Chapter 27: Prokaryotes and the Origins of Metabolic Diversity
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List unique characteristics that distinguish archaea from bacteria.
They differ in key structural, biochemical, and physiological characteristics.
2. Describe the three-domain system of classification and explain how it differs from previous systems.
Domain Bacteria – contains all the eubacteria.
Domain Archaea – contains all archaeabacteria.
Domain Eukarya – contains all eukaryotes.
This differs from the five-kingdom system, followed by the six kingdom system, and later the eight kingdom
system. It is the first system to use domains and the first to separate bacteria and archaeabacteria. It
indicates that archaea and eukarya had a closer relative than the one between bacteria and archaea.
3. Using a diagram or micrograph, distinguish among the three most common shapes of prokaryotes.
(I could not find a diagram to place here, but the common shapes are cocci which are spherical, bacilli which
are rod-shaped, and corkscrew-shaped spirochetes).
4. Describe the structure and functions of prokaryotic cell walls.
The wall maintains the shape of the cell, gives it physical protection, and prevents it from bursting in a
hypotonic solution. Most contain peptidoglycan (consists of polymers of modified sugars cross-linked by
short polypeptides).
5. Describe three mechanisms motile bacteria use to move.
By means of:
1) flagella – may be scattered over the entire cell surface or concentrated on both cell ends.
2) A group of helical-shaped bacteria called spirochetes move because of several small filaments that spiral
around the cell under the out sheath of the cell wall. The cell moves like a corkscrew as the motors of
filaments slide past each other.
3) Some prokaryotes secrete slimy chemicals and move by a gliding motion.
6. Indicate where photosynthesis and cellular respiration take place in prokaryotic cells.
In some aerobic prokaryotes, the infoldings of the plasma membrane function in cellular respiration.
Cyanobacteris have thylakoid membrane function in cellular respiration. Cyanobacteri have thylakoid
membranes the function in photosynthesis.
7. List the sources of genetic variation in prokaryotes and indicate which one is the major source.
The sexual cycles of meiosis and syngamy are an important part of genetic variation. There are three
methods of genetic recombination:
1) Conjugation – genes transferred directly from one prokaryote to another.
2) Transformation – genes are taken up from the surrounding environment.
3) Transduction – genes transferred by means of a virus.
Mutation is also a major source of genetic variation.
8. Distinguish between autotrophs and heterotrophs.
Autotrophs – an organism that can make its own energy from organic compounds and needs only inorganic
carbon dioxide as its source of carbon.
Heterotroph – an organism that needs at least one organic nutrient as a source of carbon for making other
organic compounds.
9. Describe four modes of bacterial nutrition and give examples of each. Distinguish between autotrophs
and heterotrophs.
Table 27.1 Major Nutritional Modes
Mode of nutrition
Autotroph
Photoautotroph
Chemoautotroph
Heterotroph
Photoheterotroph
Energy
source
Light
Carbon
source
CO2
Inorganic CO2
chemicals
Light
Organic
Types of
Organisms
Photosynthetic
prokaryotes,
including
cyanobacteria;
plants; certain
protists
Certain
prokaryotes
(e.g.,
Sulfolobus)
Certain
Organic
compounds prokaryotes
Chemoheterotroph compounds
Organic
Most
compounds prokaryotes
and protists;
fungi;
animals; some
plants
Example: cyanobacteria.
Example: archaeabacteria of the genus sulfobolus oxidizes sulfur.
Example: saprobest parasites.
10. Distinguish among obligate aerobes, facultative anaerobes and obligate anaerobes.
Obligate – use oxygen for cellular respiration.
Facultative – will use oxygen if present, but can
also grow by fermentation in an anaerobic
environment.
Obligate anaerobes – cannot use oxygen; are poisoned by it. Some live exclusively by fermentation, others
get energy by anaerobic respiration of inorganic molecules.
11. List the three main groups of archaea, describe distinguishing features among the groups and give
examples of each.
Methenogens – energy metabolism in which hydrogen is used to reduce carbon dioxide to methane. They
are poisoned by oxygen; live in swamps and marshes. Important decomposers employed for sewage
treatment. Others live in guts of animals, playing an important role in nutrition.
Extreme halophiles – live in saline places. Some merely tolerate it while others actually require it to grow.
Form a red-purple scum from bacteriohodopsin.
Extreme thermophiles – thrive in hot environment. Their optimal temperature is 60 to 80 degrees Celsius.
Prokaryotes are most closely related to eukaryotes.
12. List the major groups of bacteria, describe their mode of nutrition, some characteristic features and
representative examples.
Proteobacteria – they are purple and photoautotrophic or photoheterotrophic.
Gram-positive eubacteria – most species are chemoheterotrophs.
Cyanobacteria – photoautotrophs with plant-like photosynthesis and they use chlorophyll a.
Spirochetes – have internal filaments which cause their corkscrew movement; chemoheterotrophs.
Chlamydias – gram-negative cell walls; obligate intracellular parasites of animals.
13. Explain why all life on earth depends upon the metabolic diversity of prokaryotes.
Prokaryotes are vital to our life cycles because as decomposers, they remove vital elements that need to
return to the soil, air, and water. They also serve to return these elements to living things on this earth.
14. Distinguish among mutualism, commensalism and parasitism.
Mutualism – both partners in symbiosis benefit from the relationship.
Commensialism – one partner benefits while the other is neither helped nor harmed.
Chapter 28: The Origins of Eukaryotic Division
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List the characteristics of protists.
A membrane enclosed nucleus, mitochondria, chloroplasts, the endomembrane system, the cytoskeleton, 9 +
2 flagella, multiple chromosomes consisting of linear DNA molecules arranged with proteins, diploid stages
in life cycles, mitosis, meiosis, and sex.
2. Briefly summarize and compare the two major models of eukaryotic origins, the autogenous hypothesis
and the endosymbiotic hypothesis.
The endosymbiotic hypothesis says that the ancestors of eukaryotic cells were endosybionts of prokaryotic
cells, living within the cell walls of larger prokaryotes. Eventually, the symbiosis became mutually beneficial
and as they became more dependent on each other, they would be inseparable.
3. Provide three major lines of evidence for the endosymbiotic hypothesis.
Some proof for the theory is that there are endosymbiotic relationships that exist today and there is great
similarity between eubacteria and the chloroplasts and mitochondria of eukaryotes.
4. List five candidate kingdoms of protists and describe a major feature of each.
Rhizopoda – naked and shelled amoebas, with broad pseudopodia for motility and feeding.
Actinopoda - occupy planktonic habitats; spherically symmetrical.
Forminifera – feed and mo with slender, interconnected pseudopodia.
Apicomplexa – parasitic with complex life cycles in animal hosts.
Zoomastigophora – use flagella for motility and feeding.
Ciliophora – cilia used for motility and feeding.
5. Distinguish among the following algal groups based upon pigments, cell wall components, storage
products, reproduction, number and position of flagella, and habitat:
a. Dinoflagellata d. Phaeophyta
b. Bacillariophyta e. Rhodophyta
c. Chrysophyta f. Chlorophyta
Table 28.2 Summary of the Candidate
Kingdoms of Protists
CANDIDATE
KINDOM
BRIEF DESCRIPTION
(with subgroups)
Archaezoa (p. 524)
Diplomonads (e.g.,
Giardia)
Mostly parasitic; lack mitochondria
Trichomonads
Microsporidians
Euglenozoa (p. 526) A monophyletic group of flagellates
Euglenoids (e.g.,
Euglena)
Autotrophic; flagella arise from an
anterior pocket
Parasites with a single
Kinetoplastids (e.g.,
mitochondrion and associated
Trypanosoma)
extranuclear DNA
Cells with subsurface cavities
Alveolata (p. 527)
(alveoli)
DinoflagellatesÊ(e.g., Flagella arise from grooves formed
Pfiesteria)
by internal cellulose plates
Parasites whose infectious stages
Apicomplexans (e.g., have an apical complex of
Plasmodium)
organelles that penetrate the host
cell
Ciliates (e.g.,
Have two types of nuclei; use cilia
Paramecium)
for motility and feeding
Unicellular and multicellular; cells
often have flagella of unequal
length; long flagella usually have
Stramenopila (p.
rows of fine, hairlike projections;
533)
chloroplasts probably derived from
endosymbiotic eukaryotic cells
Freshwater and marine unicellular
Diatoms
photoautotrophs with two-part
(bacillariophytes)
siliceous cell walls
Mostly freshwater unicells; some
Golden algae
colonial; cell walls pectic/siliceous;
(chrysophytes)
most are photoautotrophic, some are
mixotrophic
Mostly marine, multicellular; cell
Brown algae
walls of cellulose and other
(phaeophytes)
polysaccharides; photoautotrophic
Water molds, white Unicellular or coenocytic
rusts,downy mildews heterotrophs (decomposers and
(oomycotes)
parasites); freshwater and terrestrial;
Rhodophyta (p.
539)
Chlorophyta* (p.
540)
cell walls made of cellulose
Red algae; most are multicellular
photoautotrophs; cell walls of
cellulose and other polysaccharides;
no flagella; some heterotrophic
parasites
Green algae; mostly freshwater,
some marine and terrestrial;
unicellular, colonial, and
multicellular photoautotrophs; cell
walls of cellulose; free-living and
symbiotic
*Candidate member of Kingdom Plantae.
6. Distinguish between isogamy and oogamy; sporophyte and gametophyte; and isomorphic and
heteromorphic generations.
Isogamy – a condition in which male and female gametes are morphologically indistinguishable because
they have fused together.
Oogamy – male and female gametes differ, such that a small, flagellated sperm fertilizes a large, nonmotile
egg.
Sporophyte – multicellular diploid form in organism undergoing alteration of generations that results from a
union of gametes and that meiotically produces haploid spores that grow into the gametophyte generation.
Gametophyte – multicellular haploid form that mitotically produces haploid gametes that unite and grow
into sporophyte generations.
Isomorphic – alternating generations in which gametophytes and sporophytes look alike, although they
differ in chromosome number.
Heteromorphic – a condition in which sporophyte and gametophyte generations differ in morphology.
Chapter 29: Plants and the Colonization of Land
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List characteristics that distinguish plants from organisms in the other kingdoms.
Nearly all are terrestrial; aerial parts of the plant are coated with a waxy cuticle that helps prevent
desiccation. Oxygen and carbon dioxide diffuse between the interior of leaves and the surrounding air
through microscopic pores called stomata. Have cell walls made of cellulose and carbohydrates stored in the
form of starch, generally in chloroplasts and other plastids.
2. Diagram a generalized plant life cycle indicating which generation is the sporophyte/ gametophyte, which
individuals are haploid/diploid, where meiosis occurs and where mitosis occurs.
3. Distinguish between the categories division and phylum.
Division – for major plant groups within a kingdom; corresponds to:
Phylum in the animal kingdom (the highest unit of classification).
4. Using the classification scheme presented in the text, list the plant divisions; give the common name for
each; and categorize them into nonvascular, vascular seedless and vascular seed plants.
Table 29.1 A Classification of Plants
Common
name
Approximate
number of extant
species
Bryophyta
Mosses
12,000
Liverworts
6,500
Hornworts
100
Nonvascular Plants
(Bryophytes)*
Division
Division
Hepatophyta
Division
Anthocerophyta
Vascular Plants
Seedless Vascular
Plants**
Division Lycophyta
Division
Sphenophyta
Division Pterophyta
Seed Plants
Gymnosperms
Division
Coniferophyta
Division
Cycadophyta
Division
Ginkgophyta
Division Gnetophyta
Angiosperms
Division Anthophyta
Lycophytes
1,000
Horsetails
15
Ferns
12,000
Conifers
550
Cycads
100
Ginkgo
1
Gnetae
70
Flowering
plants
250,000
*Use of the term nonvascular for bryophytes must be qualified: Waterconducting tissue is present in some species.
**Seedless vascular plants called psilophytes, or whiskferns, were placed in a
separate division until recently. Most botanists now include these plants in the
fern division (see Challenge Question 1, p. 560).
5. List and distinguish among three division of Bryophyta.
Mosses – has a spongy quality that enable it to absorb and retain water. Each plant in the moss mat grips
the substratum with rhizolds (elongate cells or cellular filaments). Most photosynthesis occurs in the upper
plants. The haploid generation is the dominant one in structure called sporangium. The diploid sporophyte
is generally smaller and shorter lived.
Liverworts – bodies divided into lobes (some). Lifecycle much like moss. In sporangia are coil-shaped cells
that spring out of the capsule when it opens, helping to disperse the spore. Can also reproduce asexually
from small bundles called gammae, bounced out of cups on the gametophyte surface by raindrops.
Hornwarts – distinguished by their sporophytes (elongated capsules that grow like horns from the mat-like
gametophyte). Photosynthetic cells each have a single large chloroplast rather than many smaller ones.
6. List and distinguish among the four extant divisions of seedless vascular plants.
Division Psilophyta – only two genera. The most common one is Psilotum (whiskfern). In diploid
sporophyte generation it has dichotomous branching. True roots and leaves are absent. Bears a horizontal
stem with gairs called rhizoids and have emergences which don’t have vascular tissue.
Division Lycophyta (Lycopods) – by the Carboniferous period the division had split into two evolutionary
lines. One – woody trees and two – small and herbaceous. The giant ones thrived in swamps for millions
of years and became extinct when swamps for millions of years when swamps began to dry up. Small plants
survived and the common name is the club moss/ground pine. Many Lycopodium are tropical plants that
grow on trees and others grow close to the forest floor in temperate regions. Sporangia of these are born on
sporophylls (leaves specialized for reproduction) into bisexual gametophytes which can then live
underground for ten or more years nurtured by fungi until it grows.
Division Sphenophyta (horsetails) – during the Carboniferous period species grew as tall as 15 m. Surviving
are 15 species of a single genus – Equisetum. These are the sporophyte generation. Meiosis occurs in
sporangia and haploid spores are released: they are photosynthetic and free-living. Are homosporous
(bisexual gametophyte).
Division Pterophyta (ferns) – by far the most represented in modern floras. More than 12,000 species; mst
diverse in tropics, but also forests. Leaves are larger than lycopods and probably evolved in a different way.
Most leaves (fronds) have leaves divided up into several leaflets. Have sporangia arranged in clusters (sori)
and equipped to spring and be airborne, blown far from their original habitat, yet restricted to damp
habitats.
7. Distinguish between homosporous and heterosporous.
Homosporous – have spores that turn into bisexual gametophytes.
Heterosporous – the plant makes two different kinds of spores, producing male and female gametophytes.
8. Distinguish among spore, sporophyte, sporophyll and sporangium.
Spore – in the life cycle of a plant or alga undergoing alternation of generations, a meiotically produced
haploid cell that divides mitotically, generating a multicellular individual, the gametophyte, without fusing
with another cells.
Sporophyte – the multicellular diploid form in organisms undergoing alternation of generations that results
from a union of gametes and that meiotically produces haploid spores that grow into the gametophyte
generation.
Sporophyll – leaves specialized for reproduction.
Sporangium – the place where diploid sporophyte mosses produce haploid spores through meiosis.
9. Point out the major life cycle differences between mosses and ferns.
Differences: Moss’ gametophyte is the prevalent generation in the cycle. There are male and female
gametophytes. In the sporangium at the top of the sporophyte stalk, meiosis occurs and haploid spores
develop. When the sporangium bursts, the spores scatter. Haploid spores grow into a new gametophyte.
Fern’s gametophytes are bisexual and their spore develops into a gametophyte that is sustained by
photosynthesis. Spots on the underside of leaves are sporangia and the release spores which make
gametophytes.
Similarities: In both sperm swim through moisture to fertilize the egg in the archegonium. Both fertilized
sporophytes emerge from the gametophyte.
Chapter 30: The Evolution of Seed Plants
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. Describe the adaptations of seed plants that have contributed to their success on land.
Four major periods of adaptation:
First: The origin of aquatic ancestors, etc. The first adaptation was the cuticle formation, jacketed
gametangia which protects gametes and embryos. Vascular tissues also evolved early.
Second: Diversification of vascular plants – they lacked seeds.
Third: The origin of the seed – protected embryos from desiccation; gave rise to gymnosperms (“naked
seeds” not in chambers).
Fourth: Emergence of flowering plants. Flower serves as the container to store seed.
2. List the four divisions of gymnosperms.
Division Coniferophyta
Division Cyandophyta
Division Ginkgophyta
Division Gnetophyta
3. Describe the structures of ovulate and pollen cones of a pine and distinguish between the two.
Small pollen cones produce small microspores that develop into male gametophytes. The contain hundreds
of sporangia in reproductive leaves. Larger, more complex ovulate cones, usually develop on a different part
of the tree and make larger megaspores that develop into female gametophytes. It consists of many scales,
each with two ovules. Each ovule is enclosed by a nucellus and an opening called the micropyle.
4. Describe the life history of a pine and indicate which structures are part of the gametophyte generation
and which are part of the sporophyte generation.
The pine tree is a sporophyte with sporangia on its cones. The gametophyte generation develops from
haploid spores within it. Conifers are heterosporous and the separate spores are produced in two different
types of cones. The cones take nearly three years to mature and then the scales will separate and the seeds
travel on the wind. A seed that lands in a good, habitable place germinates and its embryo emerges as a pine
seedling.
5. Distinguish between pollination and fertilization.
Pollination – the placing of pollen onto the stigma of a carpel by wind or animal carriers, a prerequisite to
fertilization.
Fertilization – the union of haploid gametes to produce a diploid zygote.
6. List and give examples of the two classes of Anthophyta.
Monocots: pink lady’s slipper orchids
Dicots: blue violet
7. Compare the life cycles of mosses, ferns, conifers, and flowering plants in terms of:
a. Dominant life cycle stage (gametophyte/sporophyte)
b. Whether they are homosporous or heterosporous
c. Mechanism of gamete transfer
Mosses:
a. Gametophyte
b. heterosporous
c. flagellated sperm swims through film of water to egg
Ferns:
a. sporophyte
b. homosporous
c. flagellated sperm
Conifers:
a. sporophyte
b. heterosporous
c. sperm windblown
Flowering platns:
a. sporophyte
b. heterosporous
c. pollen transferred by wind/animals
8. Describe some refinements in vascular tissue that occurred during angiosperm evolution.
In angiosperms, the vessel elements are cells wider and shorter that the original tracheids from which they
originate. They are arranged end to end, making a continuous tube more specialized for transport and
reinforced by fiber cells which evolved the same way.
9. Explain how evolution of the flower enhanced the reproductive efficiency of angiosperms.
The ovary has dropped to a position below the petals and sepals, where ovules are better protected.
10. Define fruit and explain how fruits are modified in ways that help disperse seeds.
Fruit – a mature ovary. Fruit protects dormant see and aids in their dispersal.
Modifications: 1) Some fruit has seed that acts as kites or propellers that aid in dispersal by wind. Most use
animals to carry seeds.
2) Some have fruits as burrs that cling to animal fur or human clothing.
3) If the fruit is eaten, the seed passed through unharmed and may grow where it is left in the end.
11. Diagram the generalized life cycle of an angiosperm, identify which structures are haploid, and explain
how it differs from the life cycle of a pine.
Chapter 31: Fungi
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List characteristics that distinguish fungi from organisms in other kingdoms.
They differ in nutritional mode, structural organization, and growth and reproduction.
2. Explain how fungi acquire their nutrients.
Heterotrophs – they ingest food and acquire nutrients by absorption. They digest outside their bodies by
secreting powerful hydrolytic enzymes into food; decompose complex molecules to simple ones so they can
be absorbed.
3. Explain how non-motile fungi seek new food sources and how they disperse.
Saprobic – get their nutrients from dead/decaying matter.
Parasitic – absorbs from another living organism.
Mutualistic – absorbs from another organism but balances it out by helping the organism.
4. Describe the basic body plan of a fungus.
Bodies made of hyphae (threads composed of tubular walls surrounding plasma membranes and cytoplasm).
They form an interwoven mat (mycelium); the feeding network. The hyphae are divided into cells by crosswalls or septa. They have pores large enough to allow ribosome, mitochondria, and nuclei to flow from cell
to cell. The cell walls are made of chitin.
5. Distinguish between septate and aseptate (coenocytic) fungi.
Septate – fungal hyphae divided into cells by cross-walls (septa).
Aspetate – their hyphae are not divided into cells. They consist of a continuous cytoplasmic mass with
hundreds or thousands of nuclei. They result from repeated division of nuclei without cytoplasmic division.
6. Distinguish among fungi and list some common examples of each.
Zygote – mostly terrestrial and live in soil or on decaying plant and animal matter. Ex. Bread mold.
Sac – Include some of the most devastating plant pathogens. Many are important saprobes. Half live with
algae in symbiotic relationships. Defining feature – production of sexual spores and sac-like asci. Ex.
Truffles.
Club – include mushrooms, etc. Club-shaped; important decomposers of wood and other plant material.
Includes mycorrhiza – forming mutualists and plant parasites.
7. Describe asexual and sexual reproduction in Zygomycota, Ascomycota, and Basidiomycota, and the sexual
structure that characterizes each group.
Zygomycota – sexual; neighboring mycelia of opposite mating types form hyphal extensions which undergo
plasmogamy and haploid nuclei pair off, forming dikaryotic zygosporangium. Cells develop a rough, thick –
walled coating that resists dry conditions and other harsh environments for months. Sometimes karyogamy
occurs, follwed by meiosis. Zygosporangium breaks dormancy, germinating into a short sporangium that
disperses the genetically diverse, haploid spores. These germinate and grow into mycelia. They can
reproduce asexually by forming sporangia.
Ascomycota – haploid mycelia of opposite mating types became intertwined. One (female) produces an
ascogonium, which receives many haploid nuclei from the antheridium of the “male.” Ascogonium gives
rise to dikaryotic hyphae that are incorporated into an ascocarp, the cuo of a cup fungus. Tips of the
ascocarps dikaryotic hyphae are artitioned into asci. Karyogamy occurs and meiosis yields four haploid
nuclei. Each divides by mitosis and produces 8 in total. Cell walls develop and form ascopores; when
mature they are dispersed as the ascus jars collapse into each other. These in turn give rise to new haploid
mycelia. They can also reproduce asexually through conidia.
Basidiomycota – haploid basidiospores germinate in a suitable environment and grow into shortlived
haploid mycelia. Undiferentiated hyphae from two haploid mycelia (opposite mating type) undergo
plasmogamy, creating dikaryotic mycelium that grows faster than the parent haploid mycelium which it
eventually crowds out. Environmental changes cause the mycelium to form compact masses that develop
into mushrooms. Cytoplasm streaming into the mushroom causes it to “pop up” overnight. Karyogamy
occurs in the terminal dikaryotic cells that line the surfaces of the gills. Each cell swells to form a diploid
basidium which, after meiosis, yields four haploid cells. The basidium then grows four appendages and one
haploid nucleus enters each appendage and develops into a basidiospore. When mature, these are propelled
slightly into the spaces between the gills and after they drop below the cap, they are disposed of by the wind.
8. Explain the difference between conidia and ascospores.
Conidia – a “naked”, asexual spore produces at the ends of hyphae in ascomycotes. Not formed inside
sporangia.
Ascospores – products of sexual reproduction in ascomycetes. They are eight in total and nuclei are
surrounded by a cell wall; made in the ascus.
9. Describe the anatomy of lichens and explain how they reproduce.
Lichens – a symbiotic association of millions of photosynthetic microorganisms tangled in a mesh of fungal
hyphae. Some key similarities – fungus usually gives it its overall shape and structure. Algal components
are found in the inner layer below lichen surface. They reproduce sexually – by forming ascocarps (and
rarely basidiocarps). Asexual reproduction occurs commonly because of multiple organisms.
Chapter 32: Introduction to Animal Evolution
OBJECTIVES
After reading this chapter and attending lecture, the student should be able to:
1. List characteristics that distinguish animals from organisms in the other four kingdoms.
They are multicellular, heterotrophic eukaryotes. They must take in preformed organic chemicals. Most do
this by ingestion of organisms or organic material as decomposers. They typically store carbohydrates as
glycogen. They lack cell walls and have unique types of intercellular junctions. They have two types of body
tissue, nervous and muscle tissue. They reproduce sexually and the diploid stage is dominant. They have
small, flagellated sperm and a nonmotile egg. Zygotes undergo cleavage during the blastula stage.
Following is the gastrulation stage during which embryonic adult tissues form. Some are born looking just
as they will in adulthood and others are born first in a larval stage and later undergo metamorphosis.
2. Distinguish between radial and bilateral symmetry.
Radial – animal with top, bottom, or oral or aboral, but no head, rear, left or right.
Bilateral – have dorsal, ventral, anterior, and posterior (top, bottom, head, end and tail).
3. Outline the major phylogenetic branches of the animal kingdom, which are based upon grade of
organization; symmetry and embryonic germ layers; absence or presence of a body cavity; and protostomedeuterostome dichotomy.
(The major phyla and what is under them is something I already know without having to write it down).
4. Distinguish among acoelomate, pseudocoelomate and coelomate.
Acoelomate – animal without a coelom.
Pseudocoelomate – animal with a coelom, but it’s not made up completely of mesoderm tissue.
Coelomate – has a coelom (fluid-filled cavity that cushions organs) made all of mesoderm tissue derivatives.