Test 1 Flashcards
Chorde
String
notos
back
oura
tail
Kephale
Head
Broad divisions among metazoans based on ______________
number of germ layers
how many germ layers are there
3: Ectoderm. Endoderm, Mesoderm
Ectoderm
superficial skin, lining of most anterior & most posterior digestive tract, nervous system
Endoderm
rest of the digestive system lining, gut lining ,respiratory surfaces, taste buds, thyroid, parathyroid, thymus
Mesoderm
(everything else) muscles, skeleton, connective tissue, circulatory & urogenital system
Deuterostomes have at least ___ differences
3
Radial Cleavage
cleavage planes occur perpendicular or parallel to each other
Spiral Cleavage
cleavage planes occur at oblique angles
Indeterminate cleavage
cells may develop into whole organism if separated
Determinate cleavage
cells lose capacity to develop into a
complete embryo if separated
Protostomia vs Deuterstomia
Deuterostomes have
1. Radial cleavage
2. Indeterminate cleavage
3. The blastopore is at the posterior, and becomes the anus rather than the mouth
Chordate characteristics include:
- A notochord (stiffening rod, not compressible but flexible from side to side)
- A dorsal, hollow nerve cord
- A post-anal tail
- An endostyle (or thyroid gland)
cordata subphyla
- Cephalochordates (Lancelets)
- Urochordata (Tunicates)
- Vertebrata
Amphioxus: Vertebrate-like features
– Notochord under hollow dorsal nerve chord
– Complete gut & post-anal tail.
– Perforated pharynx, endostyle
– Segmentation (myomeres)
Amphioxus: Vertebrate-like features NOT FOUND
- No cranium
– No special sense organs and associated brain
– No kidneys
– No heart
Life is energetically _______ for
vertebrates
Expensive
Subphylum Vertebrata-
Characteristics
- Spinal cord
-serially arranged vertebrae that make up the spinal column - Cranium
-bony cartilaginous or fibrous
-surrounds the brain (cephalization) - Head, sense organs and brains
-prominent
-contains sense organs
-tripart brain: forebrain (olfaction), midbrain (vision), hindbrain (hearing and balance) - Complex endocrine organs
-produce to regulate hormones - Muscularized gut tube
-efficient processing of large amounts of food - Multi-chambered heart
-distribute nutrients and respiratory gases - Mineralized tissues
-(calcium mainly) in tissues to create rigidity - Gills (derived from the endoderm)
there are ____ principle types of tissue
4:
1. Epithelial
2. Muscular
3. Neural
4. Connective
Epithelial Tissue
-protect internal environment
-regulate exchange of material
-consist of one or more layers of cells connected to each other AND to a basal lamina
Muscular Tissue
Contain filamentous proteins actin and
myosin which cause contractions and exert force
there are ___ types of Muscle tissue
3 types:
1. Skeletal: responsible for gross body
movement
2. Smooth: responsible for influencing
movement of substances into/out of/within the body
3. Cardiac: heart muscle- contraction moves blood through the body
- Neural Tissue
Transmit signals from one part of the body to another
there are ___ types of nueral tissue
2 Types:
1. Neurons: transmit information as
electrical or chemical signals
2. Glial cells: insulate neurons from
surrounding cells
- Connective Tissue
-Connective tissue provides structural
support, protection and strength
-some connective tissue is mineralized
Includes:
– Mineralized tissues such as bone and
cartilage
– Other tissues such as adipose tissue, blood and flexible tendons and ligaments.
Mineralized connective tissue is …
-cells that secrete a proteinaceous tissue matrix, usually composed of collagen and crystals of calcium hydroxyapatite
-arranged on a matrix of collagenous fibers with alternating directions to provide strength, and lightness, and prevents cracks from spreading
3 types of bone in vertebrates
- Dermal bone:
-formed in the dermis of the skin (exoskeleton)
-no cartilaginous precursor - Endochondral bone:
-formed from a cartilage precursor
-The internal skeleton of bony fishes and tetrapods - Perichondral bone: forms in the perichondral membrane around cartilage and bone
Teeth
-Harder than bone and more resistant to wear
-Composed of dentine and enamel
Vertebrate Organ Systems (10)
- Integumentary system
- Skeletal system
- Muscular system
- Nervous system
- Endocrine system
- Respiratory system
- Circulatory system
- Digestive system
- Excretory system
10.Reproductive system
Integumentary system
-Skin and its derivatives
-Functions include protection, regulation of body temperature, sensation, and communication
-Two layers:
1. epidermis
2. dermis
Skeletal System
-Bones and joints
-Functions include: protection of organs, movement, storage of fat and minerals, production of blood elements
-Early vertebrates evolved a dermal skeleton
-Components include the vertebrae, chondrocranium and the gill arch skeleton
-Axial vs appendicular skeleton
Muscular system
Three types of muscle tissue:
1. Smooth muscle in the walls of visceral organs and blood vessels. (Involuntary control)
2. Cardiac muscle
3. Skeletal muscle for voluntary control of contraction
Nervous system
-Regulates and integrates information from the external and internal environment to control motor, sensory,
involuntary body function, and higher functions such as cognition
-Electrical and chemical signaling
-Neurons are the basic unit
-In jawed vertebrates the neuron axons are encased in a myelin sheath
-Central vs peripheral nervous system
- Endocrine system
-Regulatory and control system.
-Consists of separate endocrine glands
-Transfers information around the body via hormones
-Short and long term changes in the body.
Respiratory system
-Ancestral chordates probably relied
on diffusion of gases across a thin skin
-Some extant vertebrates use cutaneous respiration. e.g.,amphibians
-Respiratory surfaces include gills, skin and lungs.
-Water or air is pumped over the respiratory surface(s)
-Pumps include mouth and oral cavity, rib cage and diaphragm.
Circulatory system
-Closed circuit: arteries are connected to veins via capillaries
-Blood (liquid plasma & formed elements including erythrocytes, leukocytes, thrombocytes) carries oxygen and nutrients to the cells, removes carbon dioxide and metabolic waste products, and distributes hormones
Digestive system
-Feeding: ingesting and chewing (mechanical breakdown)
-Digestion: breakdown of complex molecules that begins with enzyme action in the mouth and continues in the stomach and small intestine.
Excretory system
-Kidneys: disposal of waste products
(primarily nitrogenous waste) & regulation of water and minerals
-Tetrapods use kidneys but fishes & amphibians also use the gills and skin
Reproductive system
-Vertebrate gonads release gametes
-Single gonad in cyclostomes and double in gnathostomes
-Two modes:
1. Oviparity- lay eggs that develop outside of body
2. Viviparity- retain eggs within the mothers body until development is complete
who is Carl Linnaeus?
-organized organisms into hierarchical classification system
-father of modern taxonomy (binomial nomenclature)
proto
one
deutero
second
stomia
mouth
Tunicates
-sea squirts
-filter feeding
-mostly sedentary marine animals
New features for early Jawless vertebrates
- Anatomically distinct head, including a tripartite brain enclosed by a cartilaginous cranium
- Pharyngeal musculature: powers the gills to draw in water through the mouth (gills used for respiration too
Gathostomes
jawed vertebrates (sharks, rays chimeras)
Jaws improve the strength and effectiveness of gill ventilation later for capturing and holding prey
Osteichthyes
Bony Fishes (Ray Finned Fishes, aka Actinopterygii) gave Rise to Sarcopterygii (Fleshy Fins)
Fin is a series of bones extending from body with a layer of tissue layered around.
Sarcopterygii
fleshy Finned Fish
coelacanths and give rise to Rhipidistia
Sarcopterygii fin
one single bone and tissue
characteristics of coelacanths:
- Nocturnal,
- feed on small fishes, squids & octopuses
- have a vestigial lung filled with fat, which is less dense than water
- viviparous reproduction
Rhipidistia
Represented by lungfishes gave Rise to tetrapods
closest related organism to terrestrial organisms
Rhipidistia major adaptation
partially divided ventricle heart to separate oxygenated blood from deoxygenated blood
Tetrapods are divided into ___ groups
2,
1.Lissamphibia (includes common amphibians)
2. Amniota -> Evolved the amniotic egg for Embryonic development
Lissamphibia includes ___ main groups of animals
3.
1) Frogs -> long hind legs, short stiff bodies
2) Salamanders -> Front and back limbs of equal length
3) caecilians -> limbless Burrowers
common Features of Lissamphibia
moist permeable skin
separate larval/adult lifeforms CEX. Frog vs Tadpole)
No scales on the skin, Respiration occurs with skin cells
- All are carnivorous, feeding on whatever is available
- Terrestrial forms can extend their tongue out to capture prey
- operculum columella complex: two bones in the inner ear involved in transmitting sounds - -
- Eyes sensitive to Blue Light
Amniota
includes mammals, Reptiles, Birds
Amniota embryonic development
a fluid-filled sack providing nutrients
may be internal Maternal body within an egg that lays and hatches
Amniotic egg has _____ membranes
3
1) Amnion -> inner membrane, cushioning
(2)chorion 3) Allantois) mainly for gas exchange, protection
Amniota is divided further into __ groups
1) synapsida -> mammals, platypus, Echidnas
2) Sauropsida -> Reptiles, Birds
types of mammals
1) Marsupial offspring raised in external pouch
2) placental -development completed inside the mother
Early Vertebrates
- jawless
- Had a distinct head with tripartite brain
enclosed in cartilaginous cranium - Pharyngeal muscles previously
used for filter feeding now used to draw
water into the mouth for respiration. - More active than nonvertebrate chordates
Two Superclasses
A. Agnathans
B. Gnathostomes
Agnatha:
the jawless vertebrates
Two major lineages of Agnathans
A. Cyclostomes
B. Ostracoderms
Cyclostomes
- Members still extant – hagfish and
lampreys - Jawless and without mineralized tissues
- “Primitive”
- Lack specialized reproductive ducts
- have a single nostril.
Cyclostomes unique features
- Single median nostril
- Unarticulated gill arch skeleton
- Velum
- Tongue with keratinous teeth
- Trunk muscles that extend into the head and around
the eyes. - Unique immune system
Hagfish- Myxiniformes
- Approx 75 species
- Worldwide distribution in marine environments
- Scavengers and predators of the deep seas (Slime glands)
- Pharynx is more posterior than other groups.
- Gill openings on side of body
Lamprey- Petromyzontiformes
- freshwater or anadromous agnathans.
- Many are parasitic of other fish as adults
- Have a single nasal opening on the top of
the head
The larval stages of lampreys…
live in streams buried in the sediment
filter-feed for 3-7 years
Adult lampreys
- attach onto their host via the suctioned round mouth
- Contain a simple digestive system feeds on blood& tissue fluids from host
The conodonts
- Hypothesized to be vertebrates based on
notochord, myomeres, and large eyes. - Mineralized tissues may have evolved
evolved convergently with hard tissues of
other vertebrates
Ostracoderms
- No jaws, ie Agnathans
- Extensive dermal bone (So more derived than cyclostomes)
- Single nostril on the top of
the head. - Tubular gill openings
- Notochord in adults
- Few or no paired fins
gnathostomes Can be divided into ___ distinctive clases
4
1. Placoderms: highly specialized extinct armored fishes
2. Acanthodians: extinct “spiny sharks”
3. Chondrichthyans: cartilaginous fish
4. Osteichthyans: bony fishes (or bony vertebrates)
Gnathostomes Derived characteristics include
jaws and two sets of paired limbs that permitted new feeding behaviors and other
manipulations
Jaws and Teeth
Extant gnathostomes have teeth on their jaws
Bony fishes & tetrapods have teeth
embedded in jaw
Cartilaginous fish have teeth
formed with skin
Evolution of teeth must have happened ____the jaws were formed
after
how many kinds of teeth
4.
1.Tooth Whorl (sharks)
2.Acrodont (gator)
3. pleurodont (bony fish)
4. thecodant (mamals)
_________ __________ were the first paired appendage to evolve
Pectoral fins
Placoderms
- abundant during the Devonian period (~400 mybp)
- Have a bony shield on the anterior portion of the body- divided into separate head & trunk parts
- Had mineralized endoskeleton
- Synarcual
- Primarily marine but some lived in freshwater or estuarine habitats
Dunkleosteus
An extinct placoderm fish from the late Devonian
period up to 33 feet
Acanthodians
- Extinct lineage with spines on their anterior
portion - called “spiny sharks”
- Had many paired fins (in addition to the pectoral & pelvic fins of other gnathostomes)
