Transcript Lecture #14 Date ______

UNIT X – KINGDOM ANIMALIA
Big Campbell – Ch 32 - 34, 40, 44, 46, 53 - 55
Baby Campbell – Ch 18, 20, 25, 27, 36, 37
Hillis – Ch 23, Beginning of Chapters 29-40, 42-45
I. ORIGINS OF KINGDOM ANIMALIA
I. ORIGINS OF KINGDOM ANIMALIA, cont
I. ORIGINS OF KINGDOM ANIMALIA, cont
II. INTRODUCTION TO KINGDOM ANIMALIA
• Shared Characteristics
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 Most have
 Extracellular Matrix
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 Regulatory Genes for Embryonic Development
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III. CLASSIFICATION OF ANIMALS
• Based on . . .
A. Presence or absence of true tissues
B. Symmetry
C. Development of germ layers
D. Presence of body cavity
E. Embryonic development
A. Tissues
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Metazoa (Parazoa)
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Eumetazoa
III. CLASSIFICATION OF ANIMALS, cont
B. Symmetry
• Asymmetry
• Radial
• Bilateral
III. CLASSIFICATION OF ANIMALS, cont
C. Development of Germ Layers
III. CLASSIFICATION OF ANIMALS, cont
C. Development of Germ Layers, cont
Form various tissues & organs
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• Diploblastic Organisms
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• Most animals are triploblastic
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III. CLASSIFICATION OF ANIMALS, cont
D. Presence of Body Cavity
Only applies to triploblasts
Acoelomates
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• Pseudocoelomates
 “_____________” body cavity
 Not lined with _____________
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• Coelomates
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III. CLASSIFICATION OF ANIMALS, cont
E. Embryonic Development
• Applies to organisms with
bilateral symmetry, primarily
coelomates
• Protostomes
 Spiral cleavage
 Determinate
 Blastopore becomes mouth
 Mollusks, annelids,
arthropods
• Deuterostomes
 Radial cleavage
 Indeterminate
 Blastopore develops into
anus
 Echinoderms, chordates
III. CLASSIFICATION OF ANIMALS, cont
Morphological/Embryonic
Classification
III. CLASSIFICATION OF ANIMALS, cont
Molecular Classification
III. CLASSIFICATION OF ANIMALS, cont
• Recent Changes in Animal Phylogeny
 Based on molecular data including Hox genes, DNA sequences for rRNA,
mDNA
 Bilaterians are subdivided into 3 groups
 Deuterstomes
 Ecdysozoans
 Lophotrochozoans
III. CLASSIFICATION OF ANIMALS, cont
IV. INVERTEBRATES
• Make up 95% of all
animals
• Most scientists agree
on approximately 35
animal phyla
• 34 of these are made
up of invertebrates
IV. INVERTEBRATES, cont
Phylum Porifera
IV. INVERTEBRATES
Phylum Cnidaria
IV. INVERTEBRATES, cont
Phylum Platyhelminthes
IV. INVERTEBRATES, cont
Phylum Nematoda
IV. INVERTEBRATES, cont
Phylum Mollusca
IV. INVERTEBRATES, cont
Phylum Annelida
IV. INVERTEBRATES, cont
Phylum Arthropoda
IV. INVERTEBRATES, cont
Phylum Echinodermata
V. PHYLUM CHORDATA
V. PHYLUM CHORDATA, cont
• Derived Characters of
Chordates
 Notochord – Flexible rod located
between digestive tract & nerve
cord
 Dorsal Hollow Nerve Cord –
Eventually develops into brain and
spinal cord
 Post-anal Tail
• Divided into 3 sub-phyla:
 Urochordata
 Cephalochordata
 Vertebrata
V. PHYLUM CHORDATA, cont
Invertebrate Chordates
• Lack a true backbone
• Suspension feeders
• Closest vertebrate
relatives; appear 50
million years prior to
vertebrates
• Subphylum
Urochordata
 Tunicates, sea squirts
 Sessile as adults
• Subphylum
Cephalochordata
 Lancelets, amphioxus
 Burrow in sand of
ocean floor
VI. PHYLUM CHORDATA - Subphylum Vertebrata
• Pronounced cephalization; known as craniates
 Craniates used to describe all organisms with head including hagfish
• Neural crest
• Closed circulatory system with chambered heart
• Notochord secretes proteins that make up somites – differentiate into vertebrae,
ribs, skeletal muscles of trunk
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Agnatha
• Jawless vertebrates
• Most primitive, living
vertebrates
• Lack paired appendages
• Cartilaginous skeleton
• Notochord present throughout
life
• Rasping mouth
• 2-chambered heart
• Hagfish – no longer
considered to be vertebrates
by some taxonomists;
scavengers
• Lampreys – usually parasitic
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Chondrichthyes
• Cartilaginous fishes
• Sharks, skates, rays
• Well-developed jaws; paired fins
• Continual water flow over gills
• Lateral line system (water pressure changes)
• Internal Fertilization; may be
– Oviparous- eggs hatch outside mother’s body
– Ovoviviparous- retain fertilized eggs; nourished by egg yolk; young born live
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Osteichthyes
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Ossified endoskeleton
Scales
Operculum
Swim bladder
Ectotherms
Most numerous of all vertebrates
Ray-fined – Most common type; fins supported by long, bony rods arranged in a ray pattern; bass,
trout, perch, tuna, herring
Lobe-finned - Fins supported by rod-shaped bones surrounded by a thick layer of muscle;
coelocanth; lungfishes
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Amphibia
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First tetrapods, land animals
Frogs, toads, salamanders
Metamorphosis
Ectotherms
External fertilization; lack shelled egg
Moist skin for gas exchange
2 → 3 chambered heart
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Reptilia
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Lizards, snakes, turtles, and crocodilians
Internal fertilization
Amniotes – Eggs have shells, extraembryonic membranes which aid in gas exchange,
transfer of nutrients, protection
Ectotherms
3-chambered heart in most; 4-chambered heart in crocs
Scales with keratin
VI. PHYLUM CHORDATA - Subphylum Vertebrata
“Class Aves”
• Have many adaptations for flight
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Wings
Honeycombed bone
Feathers (keratin)
Toothless
Lack urinary bladder
One ovary
Large breastbone
• Endothermic
• 4-chambered Heart
• Fossil studies show connection
between reptiles and birds; birds
now included in Class Reptilia
• Archaeopteryx – earliest known
bird
VI. PHYLUM CHORDATA - Subphylum Vertebrata
Class Mammalia
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Mammary glands
Hair (keratin)
Endothermic
4-chambered heart
Large brains (relative to size)
Teeth differentiation
Diaphragm
Divided into three groups
– Monotremes – Egg-layers;
platypus, anteaters
– Marsupials – Embryonic
development of young completed in
pouch; kangaroos, koalas,
opossums
– Eutherians – Placental mammals;
all other mammals
V. PHYLUM CHORDATA, cont
VI. ECOLOGY
Interactions Between Organisms & Their Environment
VI. ECOLOGY
Important Terms/Concepts
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Levels of Organization
 Organism → Species → Population →
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Biomes
Food Chains
 Trophic levels
 Importance, examples of decomposers
 Comparison of energy flow vs recycling
of nutrients
 Most energy?
 Pyramid of production
 Limits on trophic levels
 Primary production provides the “energy
budget” for any given ecosystem
• Niche
VI. ECOLOGY
Nutrient Cycles
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Water
Carbon
Phosphorus
Nitrogen
VI. ECOLOGY
Ecological Succession
• Changes seen in a community following a severe disturbance
 Primary Succession
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Describes individuals colonizing virtually lifeless area with no soil; may be due to volcano, glacier
Typically begins with autotrophic bacteria; followed by lichens, mosses
Known as pioneer organisms
Gradual development of soil due to weather, decomposition of pioneer organisms
Larger organisms begin to inhabit area → eventually results in climax community
 Secondary Succession
 Results from disturbance that leaves soil intact; for example, fire
VI. ECOLOGY
Population Ecology
• Study of how and why
populations change
• Survivorship Curves
 Type I – have few young but
provide good care; seen in
humans & other large mammals
 Type II – intermediate; mortality
fairly constant over life span;
seen in some invertebrates,
lizards, rodents
 Type III – high death rates for
very young; typically produce
high number of young but
provide very little care; seen in
fish, amphibians, some
invertebrates
VI. ECOLOGY
Population Ecology, cont
• Exponential Growth
 Occurs when population is in
ideal environment
 No limiting factors
 Entire population multiplies by a
constant factor
• Logistic Growth
 Population impacted by limiting
factors
 Carrying Capacity is met
 Limiting factors may be
described as
 Density-Dependent
 Density-Independent
VI. ECOLOGY
Population Ecology, cont
• Life history traits include reproductive age, frequency of reproduction, number of
offspring, amount of parental care
• Shaped by evolution and natural selection
• Selection for life history strategies determined by population densities and
conditions
 r-selection
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Seen in uncrowded, unpredictable environments
Also known as density-independent selection
Individuals mature early and/or produce maximum number of offspring at one time
Maximizes r, the per capita rate of increase
Bacteria, weeds
 K-selection
 Typically seen in larger, longer-lived individuals
 Population is close to carrying capacity therefore competitive ability, efficient use of resources
favored
 Maturity & reproduction at later age
 Fewer young; higher degree of parental care
 Term, K refers to carrying capacity
VI. ECOLOGY
Population Ecology, cont
Human Population Growth . . .
Exponential . . .
but, it is slowing
VII. INTRODUCTION TO ANIMAL PHYSIOLOGY
• Levels of Organization
 Humans are composed of 4 tissue
types
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VII. INTRO TO ANIMAL PHYSIOLOGY, cont
• Epithelial Tissue
 Covers body and lines organs
and cavities
 Forms glands
 May secrete mucus, be
ciliated
 Held together by tight
junctions
 Basement membrane
o Anchors one side of
epithelium to tissues
beneath
o Extracellular matrix made
up of protein,
polysaccharides
 Classified according to the
number of layers of cells and
the shape of the cells
VII. INTRO TO ANIMAL PHYSIOLOGY, cont
• Connective Tissue
 Bind and support other tissues
 Consists of cells loosely organized in an extracellular matrix
 Matrix is produced and secreted by cells
VII. INTRO TO ANIMAL PHYSIOLOGY, cont
• Nerve Tissue
 Senses stimuli and transmits signals from 1 part of the animal to another
 Neuron
 Glia
VII. INTRO TO ANIMAL PHYSIOLOGY, cont
• Muscle Tissue
 Capable of contracting
when stimulated by nerve
impulses
 Fibers
 3 Types of Muscle Tissue
 Skeletal – Voluntary,
striated
 Cardiac – Involuntary,
striated, branched; makes
direct contact with other
cardiac muscle cells
 Smooth – Involuntary;
lacks striations
VII. INTRO TO ANIMAL PHYSIOLOGY, cont
VIII. PHYSIOLOGICAL REGULATION
• Fluid that surrounds cells is
known as interstitial fluid
• Temperature, water
concentration, salt
concentration, pH must be
kept relatively constant to
maintain homeostasis
• Maintained through
 Negative Feedback –
Triggers response that
counteracts the change
 Positive Feedback –
Triggers response that
amplify the change
VIII. PHYSIOLOGICAL REGULATION
Thermoregulation
• Ectothermic
 Determined by environment
• Endothermic
 High metabolic rate generates high
body heat
• Physical processes
 Metabolism
 Sum of all energy-requiring
biochemical reactions
 Energy measured in Joules,
calories, or kilocalories
(Calories)
 Metabolic rate may be
determined by
 Monitoring rate of heat loss
 Measuring amount of O2
consumed or CO2 produced
VIII. PHYSIOLOGICAL REGULATION
Thermoregulation, cont
•
Physical Processes, cont
 Conduction
 Transfer of heat between
objects in direct contact
 Convection
 Transfer of heat by
movement of air/liquid past
a surface
 Radiation
 Transfer of heat between
objects not in direct contact
 Evaporation
 Loss of heat in conversion
of liquid to gas
VIII. PHYSIOLOGICAL REGULATION
Thermoregulation, cont.
• Adaptations
 Torpor - Low activity; decrease in
metabolic rate
 Hibernation
 Estivation
 Brown Fat
 Insulation
 Behavioral Responses
VIII. PHYSIOLOGICAL REGULATION
Thermoregulation, cont.
• Adaptations, cont
 Countercurrent Heat Exchangers
VIII. PHYSIOLOGICAL REGULATION
Thermoregulation, cont.
• Human
Thermoregulation
VIII. PHYSIOLOGICAL REGULATION
Osmoregulation
• Management of the body’s water content and solute composition
• Animals may be classified as:
Osmoconformer: Marine invertebrates. Solute concentration
in sea equal to that of organism; therefore, no active
adjustment of internal osmolarity (marine animals); isoosmotic
to environment
Osmoregulator: Include marine vertebrates, freshwater
animals, land animals. Body fluids have solute concentration
different from environment. Must expend energy to regulate
water loss or gain.
VIII. PHYSIOLOGICAL REGULATION
Osmoregulation, cont
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Freshwater fishes
 Higher solute
concentration in fish →
fish gains water, loses
salt → doesn’t drink
water, excretes large
amounts of dilute urine
•
Marine fishes
 Lower solute
concentration in fish →
fish loses water, gains
salt → drinks large
amount of saltwater,
pumps excess salt out
of gills, produces small
amounts of urine
IX. ANIMAL REPRODUCTION
IX. ANIMAL REPRODUCTION
Asexual vs Sexual Reproduction
IX. ANIMAL REPRODUCTION
• Asexual
 Budding
 Regeneration
 Fragmentation
 Fission
IX. ANIMAL REPRODUCTION
Mechanisms of Reproduction
• Parthenogenesis
 Unfertilized egg
development
 Typically haploid,
sterile adults
 Daphnia, Rotifers,
honeybees
IX. ANIMAL REPRODUCTION
Mechanisms of Reproduction, cont
• Hermaphroditism
 Both male & female reproductive systems
 Occurs in earthworms, other sessile & burrowing organisms
IX. ANIMAL REPRODUCTION
Mechanisms of Reproduction, cont
• Sequential
hermaphroditism
 Reversal of gender
during lifetime
 Protogynous - female first
 Protandrous – male first
IX. ANIMAL REPRODUCTION
Sexual Reproduction
• Pheromes
 Chemical signals released by
organism
 Influences behavior, physiology of
organisms of same species
 Active in minute amounts
• Fertilization
 External
 Internal
X. HUMAN REPRODUCTION
X. HUMAN REPRODUCTION
Gamete Production
X. HUMAN REPRODUCTION
Male Anatomy
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Testes
 Contained in scrotum
 Seminiferous tubules – sperm formation
 Leydig Cells – produce testosterone & other
hormones
 Sertoli Cells
Epididymis
 Coiled tubules that sperm pass through from testis
Vas deferens
 Muscular tube that propels sperm during
ejaculation
Ejaculatory Duct
 Combines sperm from both testes; leads to urethra
Glands
 Seminal vesicles – Add fluid to protect nourish
sperm, including fructose, mucus, enzymes;
produces semen
 Prostate gland - Secretes anticoagulant, nutrients
into semen
 Bulbourethral glands – Secretes acid neutralizer
before ejaculation
Penis/Urethra
 Ejaculation - Release of semen
 Blockage of urine flow controlled by sphincters
X. HUMAN REPRODUCTION
Male Anatomy
• Human Sperm
X. HUMAN REPRODUCTION
Female Anatomy
• Ovaries
 Follicle – Egg capsule; nourishes and
protects egg
 Egg released during ovulation
 Corpus luteum – Secretes estrogen and
progesterone to maintain uterine lining;
formed from follicle after egg is released
• Oviduct
 Also known as fallopian tube
 Egg moved along through action of cilia
• Uterus
 Thick, muscular organ also known as
womb
 Endometrium – inner lining
 Cervix – opens into vagina
X. HUMAN REPRODUCTION
Fertilization
 Head of sperm contains a vesicle known as the acrosome; contains enzymes that help sperm
penetrate egg
 Acrosomal reaction – hydrolytic enzymes act on egg jelly coat
 Surface proteins on sperm bind with receptor molecules on egg
 Sperm cell membrane fuses with egg cell membrane
 Cell membrane of egg depolarizes, becomes impenetrable to sperm to prevent multiple
fertilization (polyspermy)
 Triggers increase in metabolic activity in fertilized egg (including completion of meiosis II)
X. HUMAN REPRODUCTION
Embryonic Development
X. HUMAN REPRODUCTION
Organogenesis
X. HUMAN REPRODUCTION
Gestation