BIO 12 LAB EXAM -‐ Ex 1, 2, 3
GAMETOGENESIS
OVARY
• Theca externa (visceral peritoneum) – outer connec6ve 6ssue covering (2N)
• Sacs – house of developing egg cells suspended within t. externa (2N)
• Oogonia – smaller; arise from successive mitosis of embryonic PGCs, not yet accumulated yolk (2N)
• Oocyte – larger; dark; undergo growth and meito6c prophase; yolk, glycogen, pigments (1° (2N) 2° (N))
• Theca interna – inner membrane covering each sac; smooth muscle fibers (2N)
OVARY
• OOCYTE– Nucleus/germinal vesicle – stain lighter; with prominent nuclei
– Nuclei/gemimal spots
– Follicle cells w/ darkly stained oval nuclei -‐> secretes estrogen
OVARY
• Mature ova not found in ovary – oocytes leave by hormonal sSmulaSon prior to compleSon of maturaSon / reducSon division
• First arrest: first maturaSon division– Second maturaSon division begins upon entering of eggs to oviduct
• Second arrest: at Metaphase II– Oogenesis resumes aVer ferSlizaSon
TESTIS
• Visceral peritoneum
• Numerous seminiferous tubules – within tesSs
• Spermatocysts – compartments with various stages of spermatogenesis– Spermatogonia (2N)• Tightly packed cells with lightly stained nuclei showing threads
• Near periphery of s. tubules• Increase by ordinary mitosis; with normal diploid
TESTIS
– SpermatocytesPrimary – largest s-‐geneSc cells (2N)• Early growth: w/ vesicular, lightly stained nuclei• Shows meioSc chromosomes:
– Pairing of homologous chromosomes– Crossing-‐over– Progressive chromosomal contracSon
Secondary s-‐cytes – slightly smaller cells (N)• With darkly stained nuclei• Some with highly contracted chromosomes• Haploid no. of dyads
TESTIS
– SpermaSds – produced by 2nd meioSc division by 2ndary S-‐cytes (N)• w/ haploid no. of monad• Very small; w/ slightly stained nuclei
– Spermatozoa – haploid (N)• Masses of hair-‐like structures• A^ached to sertoli cells
– All spermatogenic cells are found within spermatocysts except spermatozoa
– Cells in spermatocyst are in the same stage
TESTIS
• Leydig cells – between seminiferous tubules; secrete androgens
• Sertoli cells – elongated triangular cells, supply nutrients
• Bases a^ached to basement membrane of seminiferous tubules
• Provide mechanical support & nourishment to spermatozoa
PROPHASE I of MEIOSIS I
1. Leptotene – similar in appearance to spermatogonia but boundaries more disSnct– Found within porSons of dark row of early
spermatocytes
– w/ finely granular nuclei
– w/ masses of lightly stained beaded threads
– Display graduaSons from irregular to more circular appearance
– Chromosomes condense
2. Zygotene – homologous chromosomes side by side & gene by gene with each other– w/ convergence towards one side of nucleus (bouquet configura6on)
– Pairing without crossing over3. Pachytene – with thicker chromosomes– Chromosomes resemble minute railroad tracks winding about within the nuclear membrane w/ gently spiraled twists
– Crossing-‐over or exchange of gene6c materials between homologous chromosomes takes place
PROPHASE I of MEIOSIS I
4. Diplotene – chromosomes condense more– Becomes slightly separated while sister chroma6ds s6ll remain aTached at the centrometric region
– Separa6on is complete except at points where crossing-‐over has occurred
– Chismata – points of interchange5. Diakinesis – shortening of chromosomes; relaxa6on of pairing– Points of contact between homologues diminish– Presence of tetrads appearing like fuzzy loose loops– Chromosomes prepare for alignment
PROPHASE I of MEIOSIS I
OTHER SHIZZLE
• Increase of nucleoli in nucleus – producSon of ribosomes w/c synthesizes proteins needed for yolk producSon
• Melanin of oocytes – near the periphery• Where sperm arise from:– Acrosome cap: golgi apparatus– Head: nucleus– Neck/midpiece: mitochondria– Tail: centrioles
Early Development of the Frog
LIFE STAGES1. Gametogenesis – produce haploid cells,
gametes (N)2. FerSlizaSon – return back to 2N, zygote (2N)3. Cleavage – blastula4. GastrulaSon – morphogeneSc movements
and cells migraSng, gastrula• Ectoderm -‐> CNS, skin• Mesoderm -‐> Circulatory, Excretory• Endoderm -‐> S (WHAT), gonads• Epiboly, invaginaSon, involuSon
LIFE STAGES
5. Organogenesis – organ systems
6. Growth
7. Senescence
8. Death
DEFINITION OF TERMS
• FerSlizaSon – union of sperm and eggs
• Cleavage – rapid division of the ferSlized egg to produce more embryonic cells
• GastrulaSon – morphogenic cellular movements
• Organogenesis – differenSaSon of organs
• NeurulaSon – development of the neural tube
BLASTULATION
• BLASTULA – embryo found at end of cleavage
BLASTULA
• Animal hemisphere – comprised of smaller cells known as the MICROMERES
BLASTULA
Vegetal Hemisphere – comprised of cells known as MACROMERES
BLASTULA
• Blastocoel – cavity found during blastula stage; disappears
• Blastoderm – cells surrounds blastocoel
GASTRULATION• InvaginaSon – sinking in of cells
• Epiboly – gradual spreading and enveloping
• InvoluSon – roll inward
• First indicaSon – blastopore and dorsal lip
GASTRULA
• Blastopore – crescenic groove bordered by thickening of cells
• Dorsal lip – formed by invaginaSon of cells in the region of gray crescent; borders yolk plug; cells above make involuSon
GASTRULA
GASTRULA
• Archenteron – formed between gray crescent cells (chordamesoderm) and yolk-‐laden cells (presumpSve endoderm); becomes oral/digesSve cavity
• Chordamesoderm – dorsal roof of archenteron (becomes notochord)
GASTRULATION
• Complete gastrula: with plug finally withdrawn into archenteron
• Whole embryo: anteriorly broad & posteriorly narrow
NEURULATION
• Neural tube – primordium of the central nervous system
• Neural plate – with thickened & fla^ened ectoderm
• Neural groove – sinking of neural plate
• Neural folds/ridges – paired elevaSons alongside the groove
• PresumpSve epidermis – remaining ectoderm
NEURAL PLATE STAGE
• Neural plate – flat, thickened dorsal layer of ectodermal cells
• Chordamesoderm cells – separate into–Median axial rod– Notochord–Mesoderm– Extend laterally between presumpSve epidermis and the yolk laden endoderm lining the lumen of the archenteron
NEURAL GROOVE STAGE
• Notochord – well-‐defined tube below neural fold
• Mesoderm – thickens & penetrates farther ventrally
• Endodermal layer – more disSnct
NEURAL TUBE STAGE
• Mesodermal somite or epimere
• Neurocoel – cavity enclosed by the neural tube
• Intermediate mesoderm or mesomere – lateral to mesodermal somite
• Lateral plate mesoderm or hypomere– Soma6c Mesoderm – outer layer
– Splanchnic mesoderm – inner layer
– Coelom – space produced
TADPOOOOOLE
ECTODERMAL DERIVATIVES
Ectoder
Epiderm
Epiderm Epithelial lining mouth
Cornea
Neural
Neural
Nervous
Neural
Melanoc Splanch Denture Cranial Mening Branchi
• EPIDERMIS– O: epidermal ectoderm
– F: Skin/epidermis
– Fu: outer body covering
• MELANOPHORE– O: Neural crest
– F: Melanophore/chromatophores
– Fu: secretes melanin, for protecSon, camouflage, gives color
• EXTERNAL NARES– O: epidermal ectoderm
– F: external nares
– Fu: entrance of air
• EPIPHYSIS– O: Neural Tube– F: Pineal body/gland– Fu: secretes melatonin
• PROSENCEPHALON– O: Neural tube– F: telen, dien– Fu: CNS
• PROSOCOEL– O: Neurocoel– F: 1st & 2nd ventricles of cerebral hemisphere
– Fu: Communicates with olfactory bulb cavity; CSF passageway
• ANTERIOR CHOROID PLEXUS– O: neural tube– F: Anterior choroid plexus– Fu: Transport of CSF to brain vesicles
• ORAL SUCKERS– O: Epidermal ectoderm
– F: disappears
– Fu: adhesion and food capture
• ORAL CAVITY– O: Rupture of oral plate
– F: Buccal cavity
– Fu: buccal breathing and nutriSon
• STOMODEUM DEPRESSION– O: Epidermal ectoderm
– F: lining of mouth cavity
– Fu: covering of mouth cavity
• INTERNAL NARES– O: epidermal ectoderm
– F: internal nares
– Fu: Passageway of air
• TELENCEPHALON– O: Neural tube
– F: Telencephalon/cerebral hemisphere
– Fu: voluntary movement, consciousness, sensaSons
• TELOCOEL– O: neurocoel
– F: 1st and 2nd ventricles of cerebral hemisphere
– Fu: CSF passageway
• DIENCEPHALON– O: Neural tube– F: thalamus, hypothalamus, diencephalon
– Fu: Relay staSon; regulaSon
• DIOCOEL– O: Neurocoel– F: 3rd ventricle of telencephalon
– Fu: communicates with lateral ventricle through Foramen of Monro; CSF passageway
• OPTIC CUP– O: neural tube
– F: OpSc cup
– Fu: Regulates light entering lens
• RETINA– O: Neural tube
– F: ReSna
– Fu: has rods and cones; visual receptor
• OPTIC LENS– O: Epidermal ectoderm
– F: Lens
– Fu: Regulates light; light refracSon
• PIGMENTED EPITHELIUM– O: Neural tube
– F: Pigmented epithelium
– Fu: Outer covering of opSc cup; maintains reSnal environment
• OPTIC NERVES (II)– O: Neural crest
– F: OpSc nerves (II)
– Fu: innervates the eyes
• MESENCEPHALON– O: Neural tube
– F: OpSc lobes
– Fu: Visual center
• MESOCOEL– O: Neurocoel
– F: OpSc vesicles; aqueduct of sylvius
– Fu: Connects with caviSes of opSc lobes, CSF passageway
• INFUNDIBULUM– O: Neural tube
– F: Posterior pituitary gland
– Fu: Secretes oxytocin and vastocin
• HYPOPHYSIS– O: Neural tube
– F: Anterior pituitary gland
– Fu: secretes prolacSn and FSH
• TRIGEMINAL GANGLION– V
– O: Neural crest
– F: Trigeminal nerve (V)
– Fu: Innervates the jaw
• RHOMBENCEPHALON– O: Neural tube
– F: Cerebellum (metencephalon), medulla oblongata (myencephalon)
– Fu: Muscle coordinaSon, reflex centers
• RHOMBOCOEL– O: neurocoel
– F: Rhombocoel
– Fu: CSF passageway
• BASAL PLATE– O: Neural tube
– F: cerebellum
– Fu: Involuntary coordinaSon
• POSTERIOR CHOROID PLEXUS– O: Neural tube
– F: Posterior choroid plexus
– Fu: Transport CSF to brain vesicles
• ACOUSTICO-‐FACIALIS GANGLION – VII to VIII
– O: neural crest
– F: facial (VII) & auditory (VIII) nerve
– Fu: VII – innervates taste buds and facial muscles; VIII – innervates utriculus and sacculus
• GLOSSOPHARYNGEAL GANGLION– IX
– O: Neural crest
– F: Glossopharyngeal
– Fu: Innervates the tongue
• OTIC VESICLE– O: Epidermal ectoderm
– F: Inner ear
– Fu: Balance and equilibrium
• ENDOLYMPHATIC DUCT– O: Epidermal ectoderm
– F: Disappears
– Fu: Forms semi-‐circular canals
• SPINAL CORD– O: Neural tube
– F: Spinal cord
– Fu: sensory and motor funcSons
– Ependymal layer -‐> ependymal epithelium
– Mantle layer -‐> gray ma^er
– Marginal layer -‐> white ma^er
• CENTRAL CANAL– O: Neurocoel
– F: Central canal
– Fu: CSF passageway
• OLFACTORY EPITHELIUM– O: Epidermal ectoderm
– F: Olfactory epithelium
– Fu: ProtecSon
• OLFACTORY CANAL– O: Epidermal ectoderm
– F: Choanal canal
– Fu: Opens into pharynx and internal nares; respiraSon
ENDODERMIC DERIVATIVES
Endode
Epitheli Epitheli Liver Pancrea Thyroid Parathy Thymus Lining Urinary gamete
• PHARYNX– O: PrimiSve Gut
– F: Pharynx
– Fu: DigesSon and respiraSon pathway
• PHARYNGEAL POUCH– O: PrimiSve Gut
– F: Middle ear, eustachian tube, parathyroids
– Fu: eustachian tube allows equal pressure; secretes parathyroid hormones
• THYROID GLAND– O: endoderm
– F: Thyroid gland
– Fu: Secretes thyroxin
• ESOPHAGUS– O: PrimiSve gut
– F: Esophagus
– Fu: passageway of food to stomach
• TRACHEA– O: PrimiSve gut
– F: Trachea
– Fu: windpipes for air passage
• EXTERNAL GILLS– O: Endoderm
– F: Disappears
– Fu: tadpole respiraSon
• LUNG BUDS– O: PrimiSve gut
– F: Lungs
– Fu: RespiraSon
• STOMACH– O: PrimiSve gut– F: Stomach– Fu: enzymaSc digesSon
• GALL BLADDER– O: PrimiSve gut– F: Gall bladder– Fu: Stores bile
• LIVER– O: PrimiSve gut– F: Liver– Fu: secretes bile, removes toxins
• NOTOCHORD– O: Chordamesoderm
– F: Disappears
– Fu: PrimiSve axial skeleton support
• MIDGUT– O: Archenteron
– F: duodenum, ileum, small intesSne
– Fu: Main site of digesSne
• YOLK – O: Endoderm
– F: Disappears
– Fu: Nourishment before external gill stage
• HINDGUT– O: Archenteron
– F: Hindgut
– Fu: Further digesSon
• CLOACA– O: PrimiSve gut
– F: Cloaca
– Fu: connects LI and anus
• ANUS– O: Blastopore
– F: Anus
– Fu: ExcreSon of waste and gametes
MESODERMAL DERIVATIVES
Mesoderm
Epimere
Myotome
Skeletal muscles
Sclerotome
Vertebral column
Dermatome
Dermis of the back
Mesomere
Nephrotome
Excretory system
Gonadotome
Reproduc6ve system except
Hypomere
Soma6c mesoderm
Dermis Connec6ve 6ssues &
Splanchnic mesoderm
Connec6ve 6ssues of
Heart& blood vessels
• PRECHORDAL CARTILAGE– O: Epimere
– F: Chondrocranium
– Fa: Movement of face, head and neck
• BRANCHIOMETRIC MUSCLES– O: Epimere
– F: Mouth muscles
– Fu: Movement of face, head and neck
• HYPOBRANCHIAL CARTILAGE– O: Epimere
– F: Visceral skeleton
– Fu: Supports pharynx
• PARACHORDAL CARTILAGE– O: Epimere
– F: Intranasal plate
– Fu: Supports floor of cranium
• ANTERIOR CARDINAL VEIN– O: Splanchnic mesoderm– F: Jugular & subclavian veins
– J-‐ drains blood from tongue and lower jaw; S – drains enSre forelimb
• DERMATOME– O: Epimere
– F: Dermis
– Fu: has chromatophores (for color)
• MYOTOME– O: Epimere
– F: Appendicular skeleton, appendage muscles, skeletal trunk muscles
– Fu: supports the body
• DORSAL AORTA– O: Splanchnic mesoderm
– F: Dorsal aorta
– Fu: Supplies blood to lumbar part & kidney
• EFFERENT BRANCHIAL VESSELS– O: Splanchnic mesoderm
– F: Internal caroSd; 2-‐4 branchial
– Fu: Curves upward to visceral arches
• AFFERENT BRANCHIAL VESSELS– O: Splanchnic mesoderm
– F: external caroSd; 2-‐4 branchial
– Fu: Emerges from truncus arteriosus
• PERICARDIAL CAVITY– O: coelom
– F: pericardial cavity
– Fu: surrounds the heart
• BULBOUS ARTERIOSUS– O: Splanchnic mesoderm
– F: conus arteriosus
– Fu: receives blood from ventricle; base of all arteries
• TRUNCUS ARTERIOSUS– O: Splanchnic mesoderm
– F: Truncus arteriosus
– Fu: gives off external caroSd, receives O2 rich blood from conus arteriosus
• PARIETAL PERICARDIUM– O: SomaSc mesoderm
– F: Parietal pericardium
– Fu: Separates wall from cavity
• VISCERAL PERICARDIUM– O: Splanchnic mesoderm
– F: Parietal pericardium
– Fu: Separates heart from cavity, protects & holds heart in place
• ATRIUM– O: Splanchnic mesoderm
– F: right and leV auricles
– Fu: L receives blood for organs, R-‐lungs
• VENTRICLE– O: Splanchnic mesoderm
– F: ventricle
– Fu: pumps blood to conus arteriosus
• COMMON CARDINAL VEIN– O: Splanchnic mesoderm
– F: precava
– Fu: Enters antero-‐lateral of sinus vein
• SINUS VENOSUS– O: Splanchnic mesoderm
– F: sinus venosus
– Fu: Pacemaker for heartbeat regulaSon
• PRONEPHROS KIDNEY– O: Mesomere
– F: mesonephros kidney
– Fu: filters blood in tadpole
• POSTERIOR CARDINAL VEIN– O: Splanchnic mesoderm
– F: Post cava
– Fu: enters posterior angle of sinus venosus
• PRONEPHRIC DUCT– O: Mesomere
– F: Mesonephric duct
– Fu: connects primitve kidney to cloaca
• PERITONEAL CAVITY– O: Coelom
– F: Pleuro-‐peritoneal cavity
– Fu: contains most internal organs
• PARIETAL PERITONEUM– O: Soma6c mesoderm– F: Parietal peritoneum, smooth muscle of gut
– F: separates wall from cavity
• VISCERAL PERITONEUM– O: Splanchnic mesoderm– 3: internal caro6d, 4-‐systemic arch, 6 – pulmocutaneous artery
– Fu: brings blood to mouth, brain, tongue, larynx, jaw, dorsal esophagus, orbit, nose, lungs, skin
• CAUDAL ARTERY– O: Splanchnic mesoderm
– F: Disappears
– Fu: dorsal aorta porSon that passes to tail
• CAUDAL VEIN– O: Splanchnic mesoderm
– F: Disappears
– Fu: Carries blood to gills to be oxygenated
THINGS TO REMEMBER
• Oh oh oh to touch and feel a girl’s vagina and hymen
• Olfactory (I), OpSc (II), Oculomotor (III), Trochlear (IV), Trigeminal (V), Abducens (VI), Facial (VII), Auditory (VIII), Glossopharyngeal (IX), Vagus (X), Accessory (XI), Hypoglossal (XII)
• Some say marry money but my brother says big boobs ma^er most (s – sensory, m – motor, b – both)
REFERENCES/SOURCES
• Pics: Mul6ply sites (hTp://trishatorga.mul6ply.com/photos/album/82 , hTp://buTercupadventures.mul6ply.com/photos/album/25/7mm-‐tadpole-‐embryo , hTp://trish130.mul6ply.com/photos/album/27/Biology_12_Slides_Exercises_1-‐3 , hTp://smickydoo.mul6ply.com/photos/album/200/7mm-‐Tadpole-‐Series-‐Sec6on ) + bio classmates + Bianca de la Vega
• OTs for tadpole info• Bio 12 manual• Sir Fon6 notes