Vertebrate structure and development Flashcards
basic vert structure: features
- larger than other chordates, need sys to deliver O2 and remove waste (via blood, diffusion insufficient)
- metabolic rate much higher (need more food, switch predatory lifestyle)
- better dev sensory system
- superior locomotory abilities
- complex feeding mechanisms (eg. muscular pharynx)
- tougher integument and bones: for protection
basic vert structure: list key dev (15)
- tripartite brain protected by cranium (close concert w complex sense organs)
- lateral line present
- electroreception
- endostyle now in thyroid
- less gill slits, hav gill tissue for respiration
- gill arches support gill slits
- pharynx muscularised
- 3 chambered heart under neural control
- closed circulatory sys
- pancreas, liver, kidney present
- body fluids more dilute than seawater
- muscularised gut
- digestion extracellular (enzymes to break down, byproducts absorbed)
- caudal fin: fin rays
- W shaped myomeres
embryonic dev: ectoderm
- outer layers of skin
- ant/post lining of most parts of gut
- parts of nervous sys (incl. sensory organs)
embryonic dev: endoderm
- mid lining of gut
- lining glands assoc w gut, respiratory surfaces, tastebuds, thyroid, parathyroid, thymus glands
embryonic dev: mesoderm
- mm, skeleton, ct.
- circulatory and urogenital sys
embryonic dev: pharyngeal pouches for fish
- grooves in btw =gills
- vert lining pouches become lymphatic sys (thymus, parathyroid glands, carotid bodies, tonsils)
embryonic dev: nn cord and neural crest
nn cord: folding/ pinching off ridge of ectoderm (encoded by notochord)
neural crest: arise next to nn cord, eventually migrate and diff into myriad cell types esp head region
embryonic dev: neural crest forms
- bones and mm in head
- PNS
- portions of brain
- adrenal glands
- pigment cells
- gut secretory glands
- aorta smooth mm
mesoderm: ceolom
- aka body cavity
- mammals: pleural cavity (lungs), pericardial (heart), peritoneal (abdominal)
- animals lack lungs + diaphragm (pleuroperitoneal)
- mesoderm lining: peritoneum and pericardium
- organs suspended in cavity by mesentery
mesoderm: divides into 4 parts
- paraxial m
- lateral plate m
- midline m
- intermediate m
paraxial mesoderm: list
- dorsal
- forms into head
- also forms somites
paraxial mesoderm: somites
- extend from neck to tail, from paraxial
- diff into dermis/striated mm/bone (sclero/myo/dermatome)
paraxial mesoderm: epaxial
- stay in place
paraxial mesoderm: hypaxial
- migrate ventrally
- mm of tetrapod limbs
lateral plate mesoderm: location
- thin walled, unsegmented ventral section
lateral plate mesoderm: features
- forms all non-segmented internal parts of body
- eg. mesenteries, vascular system, peritoneum, pericardium, reproductive sys, gut mm, cardiac mm
intermediate mesoderm:
- buds
- aka nephrotomes
- kidney and gonads
midline mesoderm:
- forms notochord
- prechordal plate
list adult cell types: (5)
- epithelial
- connective
- vascular
- muscular
- nervous
connective tissue: list types (3)
- collagen
- elastin
- keratin
connective tissue: collagen and elastin + og
- key component, in vert combines w elastin for stretchable tissue
- mesoderm og
- cont to tendons, ligs, bone matrix
- major component of soft tissue in various organs
connective tissue: keratin + og
- fibrous protein
- ectoderm og
- mainly in epidermis
- hair, scales, feathers, claws, horny structures
integument: list layers (superficial to deep)
- epidermis
- dermis
- hypodermis
integument: features and function
- outer layer of vert
- skin and derivatives
- scales, glands, armour, hair
- protect and sensory functions
integument: epidermis- features
- boundary btw animal and env
integument: epidermis- og
ectoderm
integument: epidermis- contains
- many glands
integument: epidermis- function
- protection
- glands osmotic reg
integument: dermis- og
- mesoderm
- neural crest cells
integument: dermis- contains
- collagen (strength)
- blood v
- melanocytes (pigmentation)
- sensory cells (temp, pressure, pain)
- smooth mm
integument: dermis- function
- sensory
- strength
integument: hypodermis- og
- mesoderm
integument: hypodermis- contains
- collagen
- elastin
integument: hypodermis- function
- fat storage
- subcutaneous fat
mineralised tissue: hydroxyapatite features
- unique material to vert
- Ca + phosphorus resistant to acid
- 6 types comprised of collagen fibres, cells secrete proteinaceous tissue matrix, crystals of hydroxyapatite
- laid in alternate directions for strength, relatively light
mineralised tissue: list types (6)
- mineralised cartilage
- bone
- enamel
- dentine
- anameloid
- cementum
mineralised tissue: mineralised cartilage
- major component of shark skeleton
- made from chondrocytes
mineralised tissue: bone
- internal skeleton of bony fish and tetrapods
- osteocytes
mineralised tissue: enamel and dentine
- in teeth
- dentine: odontoblasts
- enamel: amyloblasts
- > 90% mineralised so preserves well in fossils
mineralised tissue: anameloid
- enamel-like substance in cartilaginous fish
- outer layer of teeth and dermal scales
mineralised tissue: cementum
- bone-like substance securing teeth to socket
bone: features
- highly mineralised but still vascularised to allow remodelling if fractures
- old bone removed by osteoclasts, relaid by osteoblasts
bone: list types (2)
- dermal
- endochondral
bone: dermal and eg
- laid down on skin
- no cartilage precursor
- earliest type of bone to evolve
- first seen in ostacoderms
- tetrapods lack dermal bone, but skull dermal in og
bone: endochondral and eg
- bony fish and tetrapods, endoskeleton laid down in cartilage
- gradually replaced by bone later in dev
SKM: axial skeleton
- essentially notochord, og backbone of chordates
- adult tetrapods remnants in IVD
- from pituitary gland to flesh tail
SKM: endodermal skeleton/ endoskeleton list full features
- structure to ensure gills kept open: gill arches
- cranium: brain
- dermal skeleton: armoured plating
- axial skeleton: vert, ribs, fin supports
- appendicular skeleton: limbs, limb girdles
skull: list 3 components
- chondrocranium
- splanchnocranium
- dermatocranium
skull: features and og- chondrocranium
- surrounds the brain
- endochondral bone
- neural crest og
skull: features and og- splanchnocranium
- supports gills
- aka gill arches
- endochondral bone
- neural crest og
skull: features and og- dermatocranium
- forms skin as outer cover
- dermal bone
- mesoderm og
skull: ant gill arches
- recruited to form jaw structure
SKM: list type cranial striated mm (2)
- extrinsic eye mm
- branchiomeric mm
SKM: eye mm features
- 6 eye mm in all vert exc hagfish (2º loss)
- innervated by somatic motor nn
SKM: branchiomeric mm
- assoc w splanchnocranium
- suck up water: feeding/ respiration
- inn by cranial nn
SKM: axial mm
- myomeres dist over several body parts will cause undulate when contracted
- this segmentation obv in fish mm (not tetrapods eg. abs)
- provides propulsion
SKM: axial mm list sections (3)
- epaxial
- hypaxial
- horizontal septum
SKM: axial mm pelvic and pectoral mm use
- steering
- breaking
energy and metabolism: process of when food is eaten
- passes through digestive tract (peristalsis)
- dissolved by digestive enzymes in liver and pancreas
- waste out through cloaca: shared exit for reproductive/urinary/digestive sys
energy and metabolism: CVS features
- primitive vert: like amphibians relied on diffusion
- need specialised gas exchange sys (lrg body size)
- in water: 1º organ= gills, air= lungs
- closed sys: veins, capillaries, aorta etc.
energy and metabolism: CVS blood function
- carries nutrients and oxygen to cells
- removes waste and CO2
- circulates hormones to target tissues
energy and metabolism: CVS blood consists
- plasma
- red blood cells
- white blood cells
- platelets
energy and metabolism: CVS heart list chambers and flow
- 3 chambered heart
- sinus venosus
- atrium
- ventricle (fish VAS)
- unidirectional controlled by valves
energy and metabolism: CVS amphibian heart
- R/L atrium
- ventricle
- no sinus venosus
energy and metabolism: CVS reptile heart
- R/L atrium
- slightly divided ventricle
- no sinus venosus
energy and metabolism: CVS bird/mammal heart
- R/L atrium
- R/L ventricle
- no sinus venosum
excretion: kidney main function and eg.
- remove waste products from blood
- control osmotic regulation
- amphibians/ fish: fils and skin play major role
excretion: vert embryo- list kidney sections (3) and which ceases function in adult vert
- pronephros
- mesonephros
- metanephros
- pronephros stops function
excretion: opisthonephric kidney
- sharks, fish, amphibians
- adult kidney of meso, metanephros
reproduction: define
- state when gametes are produced, released, and fuse to form zygote
reproduction: og of gonads and gametes
gonads: mesoderm
gametes: endoderm
reproduction: gonads features
- paired in jawed vert (not agnathans) typically lie post body wall
- only mammals testicles external
- produce hormones (testosterone, oestrogen)
reproduction: gametes features
- jawed vert: gametes travel to cloaca via special ducts (male: archinephric, female: oviduct)
reproduction: oviduct features
- adds various things to form egg
- shell, yolk
- can be enlarged to store eggs or uterus for young to dev
- eggs may be retained in case of live-bearers or laid once fertilised
coordination: list dual NS
- somatic
- visceral
coordination: somatic NS and eg
- inn structures derived from somites
- relays info to brain conscious
- pain, heat
coordination: visceral NS and eg
- inn smooth and cardiac mm
- relays sensory unconscious
- CO2 lvl in blood
coordination: list spinal nn types (4)
- somatic sensory
- somatic motor
- visceral sensory (autonomic)
- visceral motor
motor neurons: part of which NS
autonomic
autonomic NS comprised of:
- symp NS
- parasym NS
list nerves: (12)
- optic
- olfactory
- occulomotor
- trochlear
- trigeminal
- abducens
- facial
- vestibulocochlear (auditory)
- glossopharyngeal
- vagus
- accessory
- hypoglossal
how many nn for ancestral vert and amniotes?
- ancestral vert 10
- amniotes 12
which brain region likely a vert invention?
- telencephalon
ancestral vert: assoc- forebrain
- smell
ancestral vert: assoc- midbrain
- vision
ancestral vert: assoc- hindbrain
- balance
- vibration detection
forebrain: ant part features and name
- telencephalon
- coordinates inputs from sensory modalities
- birds/ mammals: enlarged into cerebrum
forebrain: cerebrum and eg
- neocortex
- sensory integration and nervous control
- sharks and hagfish independently evolved enlarged cerebrum
forebrain: post part features and name
- diencephalon
- intermediary btw sensory and higher brain areas
- pituitary and pineal glands attached
midbrain: features and name
- mesencephalon
- develops with eyes, most vert: assoc with vision
- mammals: function co-opted by forebrain
hindbrain: name parts (2)
- metencephalon
- myencephalon
midbrain: name parts of metencephalon
- comprised region called pons,
- outgrowth: cerebellum
midbrain: metencephalon features
- cerebellum (motor coordination)
- pons (relay station btw cortex and cerebellum)
midbrain: myelencephalon
- responsible basal functions such as respiration
- relay station for receptors from inner ear
sense organs derived from:
- epidermal placodes
- highly variable, derived features of all vert groups
name system part of and analysed where: smell
- somatic sensory sys
- analysed in forebrain
name system part of and analysed where: taste
- visceral sensory sys
- analysed in hindbrain
how vision in possible:
- sheet of receptors (retina) w rods and cones
- detect various wavelengths of light
how vibration detection is acheived:
- inner ear
- lateral line sys in fish
electroreception: features
- primitive vert trait
- standard in fish, sharks
- also well dev in monotremes (eg. echidna but possibly independently)
endocrine sys: function
- send info through body using hormones
- hormones created by endo glands (pituitary, thyroid) or organs w other functions (gonads, kidneys)
- control energy allocation
endocrine sys: amniotes features
- glands gathered together as major organs
- rest vert have small clusters dist around body
immune sys: features
- vert hav adaptive immunity, able to respond to all sorts novel pathogen threats
- all animals have innate immune sys
- lymphocytes hav flexible antigen recognition
immune sys: thymus gland sig
- jawed vert hav thymus gland producing lymphocytes
- agnathans don’t have this organ
immune sys: adaptive list (3)
- antibodies, humoral immune response
- cell-mediated immune response
- memory response
immune sys: innate physical barriers list (5)
- skin, hair cilia
- mucus membranes
- mucus, chemical secretions
- digestive enzymes in mouth
- stomach acid
immune sys: innate internal defenses list (4)
- inflammatory response
- complement proteins
- phagocytic cells
- natural killer cells (NK)
