xenopus development quotes
TRANSCRIPT
XENOPUS DEVELOPMENT QUOTES
“HERE THEY ARE TIPS FOR XENOPUS DEVELOPMENT”
“THE XENOPUS FROGS ARE A SPECIES OF FROG NATIVE TO SOUTH AFRICA. THEY LIVE IN PONDS”
“THE XENOPUS MATES IS CALLED AMPLEXUS, WHEN A MALE CARRIES ON A FEMALE”
“WHEN FEMALE XENOPUS LAY AND SPAWN LOTS OF EGGS, THEY WILL HATCH INTO EMBRYOS”
“STAGE I: THE OVUM”
“THE OVUM IS A SPHERICAL CELL MADE OF CYTOPLASM AND GERMINAL VESICLE. FOR STAGE I, THE EMBRYO’S SIZE IS BETWEEN 1.5-1.6 MM IN DIAMETER. IT HAS TWO SECTIONS THAT FORM THE POLES, THE ANIMAL POLE IS DARKER THAN THE VEGETAL POLE. THE ANIMAL POLE IS CALLED BECAUSE IT CONTAINS THE
CELLS FOR THE NERVOUS SYSTEM, WHILE IN THE VEGETAL POLE WHICH MEANS THE CELLS FOR THE DIGESTIVE SYSTEM”
“THE EGG FORMS A MEMBRANOUS COVERING (OR THE EGG CAPSULE) THAT SURROUNDS THE OVUM, THUS IT IS FERTILIZED. THE EMBRYO AT MATURE OVUM STAGE IS CLASSIFIED AS NF 1”
“EMBRYO AT STAGE 1”
“STAGE 2: CLEAVAGE”
“BETWEEN 2 HOURS TO 10 HOURS, THE EGG CELL DIVIDES INTO TWO COMPONENTS, KNOWN AS CLEAVAGE. IT CONTINUES TO 4, 8, 16, 32 AND SO ON. AT THE END OF THE CLEAVAGE, A CAVITY FORMS IN THE ANIMAL
POLE, THE BLASTOCELE”
“STAGES OF CLEAVAGE (PICTURE)”
“THE FIRST 3 STAGES OF CLEAVAGE ARE 2-, 2 AND 4. -2 MEANS PRIMARY 2 CELL, 2 MEANS ADVANCED 2 CELL, AND 3 MEANS 4 CELL”
“STAGES OF ADVANCED CLEAVAGE (PICTURE)
“FROM 8 CELL TO ADVANCED MORULA”
“4 MEANS 8 CELL, 5 MEANS 16 CELL, 6 MEANS 32 CELL, 6.5 MEANS MORULA, AND 7 MEANS EARLY BLASTULA”
“BLASTULA”
“THE BLASTULA IS COMPOSED OF MANY AND MANY CELLS, WHICH ARE SMALLER IN THE ANIMAL HEMISPHERE. THE VEGETAL HEMISPHERE IS PURELY MADE OF YOLK CELLS”
“AT STAGE 8, THE BLASTULA IS AT MIDDLE STAGE, AND IN STAGE 9 THE BLASTULA IS AT THE LATE STAGE, SINCE THERE’S A LARGE AMOUNT OF CELLS”
“HOW THE FATE MAP WORKS”
“A BLASTOCYST HAS FATE MAPS THAT ARE CALLED PRIMORDIAL AREAS. WHEN IT DEVELOPS, MORE OF THESE FEATURES GIVE RISE TO THE NERVOUS SYSTEM, THE BLOOD/CIRCULATORY SYSTEM, THE DIGESTIVE SYSTEM
AND THE ADHESIVE GLAND”
“STAGE 3: GASTRULA”
“THE GASTRULA STAGE MEANS WHEN THE EMBRYONIC TISSUES BEGIN TO FORM, AND THE BLASTOCELE SHRINKS IN SIZE AND THE ARCHENTERON FORMS. THE MESODERM MIGHT BE THE MUSCLE, THE ENDODERM MEANS THE
YOLK, AND THE ECTODERM MEANS THE SURFACE AND THE NERVOUS SYSTEM”
“BY 10 HOURS AN INVAGINATION OF THE BLASTOPORE FORMS DORSALLY, KNOWN AS DORSAL LIP OF BLASTOPORE”
“STAGES OF GASTRULATION”
“FROM 10 HOURS TO 15 HOURS”
“BY 10, THE BLASTOPORE INVAGINATES, BY 10.5, THE ENCIRCLING RING FORMS IN VENTRAL AND LATERAL EDGES, BY 11, THE BLASTOPORE BECOMES MORE CRESCENT, THE 11.5TH STAGE MEANS LARGE PLUG, 12
MEDIUM PLUG AND 12.5 SMALL PLUG”
“THE ARCHENTERON INVAGINATES FURTHER AS IT DEVELOPS. THE MESODERM FORMS”
“END OF GASTRULATION”
“AT THE END OF GASTRULATION, THE EMBRYO HAS BECOMING MORE OVOID IN SHAPE DUE TO SLIGHTLY INCREASED LENGTH. THE BLASTOPORE IS SLIT SHAPED AND THE AREA THAT DELIMITS THE NEURAL PLATE
FOR THE FIRST TIME”
“STAGE 4: NEURULATION”
“PROCESS OF NEURULATION IS EVIDENT WHEN THE EMBRYO FORMS NEURAL FOLDS THAT ROLL LIKE A PIN”
“AT THE BEGINNING, THE NEURAL PLATE IS DELIMITED, IN THE MIDDLE, THE NEURAL FOLDS FORM, AND FINALLY, IT CLOSES TO FORM A NEURAL TUBE”
“EARLY IN THE NEURULATION, THE NEURAL PLATE IS WIDE AT THE ANTERIOR, AND IN THE MIDDLE OF NEURULATION, THE NEURAL FOLDS ARE EVIDENT AND FORM SHARP EDGES, AND AT THE PENULTIMATE OF
NEURULATION, THE NEURAL FOLDS TOUCH AND CREATE A GROOVE. AT THE END OF NEURULATION THE NEURAL FOLDS ARE FUSED TO FORM THE NEURAL TUBE. THE VENTRAL OUTLINE FORMS A NOTCH AND THE SIDE
OUTLINES FLATTEN, AND THE GILL-JAW AREAS ARE DELIMITED”
“PRIOR TO NEURULATION, THE NEURAL PLATE IS DELIMITED, LATER ON IT FORMS SHARP EDGES THAT RESEMBLE LIKE FOLDS, AND FINALLY THE NEURAL FOLDS CLOSE TOGETHER”
“THE LENGTH OF LATE NEURULA EMBRYOS IS ABOUT 1.8 MM IN LENGTH”
“THE NEURAL PLATE IS AT THE EARLY, AND THE NEURAL FOLDS FORM AND ROLL THAT CLOSEN EACH OTHER. THE END OF THIS COMES WITH CLOSURE, FORMING A TUBE”
“NEURAL DEVELOPMENT”
IN THE EARLIEST STAGE OF NEURULATION, THE NEURAL FOLDS FORM AS PRIMORDIAL ELEVATIONS. IN THE MIDDLEMOST OF THE STAGE THE NEURAL FOLDS TOUCH EACH CLOSELY. AT THE END THE NEURAL TUBE IS
FORMED”
“STAGE 5: THE TAILBUD”
“DURING TAILBUD, THE TAIL BUD APPEARS AS A SMALL LOBE LIKE PROJECTION FROM THE POSTERIOR OF THE EMBRYO. UNLIKE THE EARLIER STAGES, THE HEART, THE DIGESTIVE TRACT, THE PITUITARY GLAND,
AND MOST OTHER STRUCTURES ARE FORMED”
“THIS CALLED THE ORGANOGENESIS. THIS MEANS AN EMBRYO HAS MORE INTERNAL STRUCTURES THAN MOST STAGES”
“IN THE EARLY OF THIS STAGE, THE TAIL BUD APPEARS AS A PROJECTING LOBE THAT FORMS FROM THE REAR. THIS WILL GROW LONGER TO FORM THE TAIL”
“AT THE MIDDLE OF THE STAGE, THE TAIL HAS GROWN LONGER AND PIGMENT SPOTS BEGIN TO APPEAR ON THE BODY”
“THIS LOOKS MORE THAT OF A LONG BODIED FORM SINCE ITS LENGTH IS 3 MM LONG”
“THE PIGMENT ON EYES ARE GREY, BUT NOT FULLY BLACK”
“AT THE END OF THE STAGE, THE BODY IS LONGER AND THE FIN FORMATIONS ARE WELL SEEN, AS WELL AS BLACKISH EYES AND PIGMENT MARKS EVERYWHERE ON BACK AND BELLY”
“THIS IS 4 MM LONG FROG EMBRYO”
“LATE IN THIS STAGE, THE EMBRYOS HATCH INTO FREE SWIMMING TADPOLES. EARLY STAGE TADPOLES HAVE PIGMENT FOUND IN THE BACK, THE BELLY AND THE FACE, AND THE EYES ARE GREY-BLACK”
“CROSS SECTIONS”
“WHEN SLICED FROM THE FACE, IT REVEALS THE ORIENTATION IS SLIGHTLY TILTED FROM THE FRONT”
“WHEN SLICED FROM THE BELLY, IT SHOWS A MASS OF YOLK, AN ENDODERMAL MASS”
“WHEN SLICED FROM THE ANTERIOR, THE PLACODE WHICH THE NOSE FORMS IS THE OLFACTORY PLACODE. THE PLACODE IS A DISC OF CELLS”
“THE SECTION IS AT THE LEVEL OF THE EYES. THE EYES CONTAIN THE RETINA, THE LENS, AND THE PLACODE”
“WHEN SLICED FROM CORONALLY, IT SHOWS THE EARS”
“THE TADPOLE AFTER IT HATCHES, AGE 3 DAYS”
“THE SECTION THROUGH THE FOREGUT, AND THE LEVEL OF THE HEART TUBE”
“THE SECTION THROUGH THE YOLK, SHOWING THE MIDGUT”
“THE SECTION THROUGH THE HINDGUT, AND AT THE LEVEL OF PROCTODEUM”
“STAGE 6: TADPOLE STAGE”
“THE TADPOLES AT 3 DAYS ARE ALREADY TO SHOW WHAT IT LOOKS LIKE NOW”
“THE INTESTINES FORM WHEN A TADPOLE GROWS, FORMING SPIRALS”
“THEY ARE 5 DIFFERENT STAGES OF TADPOLE DEVELOPMENT”
“TADPOLE AT 3 DAYS. BY NOW THE EMBRYO HATCHES AND ITS BODY IS PIGMENTED”
“TADPOLE AT 3 DAYS. THE PIGMENT ON THE EYES ARE MORE EVIDENT”
“TADPOLE AT 4 DAYS. THE INTESTINES ARE BEGINNING TO TWIST”
“TADPOLE AT 10 DAYS. BY NOW THE TADPOLE IS ABLE TO NOURISH ITS LIFE BY FEEDING. A GOLDEN SHINY ABDOMEN IS WELL FORMED. THE TADPOLE FORMS PRIMORDIAL LIMBS”
“CROSS SECTIONS”
“SECTION THROUGH THE LEVEL OF EYE”
“SECTION THROUGH THE OTIC CAPSULES”
“SECTION THROUGH THE INTESTINES”
“THE SEQUENCES OF THE INTESTINES”
“SECTION THROUGH THE TRUNK”
“STAGE 7: LATE TADPOLE”
“THE LATE TADPOLE IS A STAGE WHICH UNDERGOES FEEDING, THE GROWTH OF THE LIMBS AND EVENTUALLY METAMORPHOSE”
“THE HEAD OF THE TADPOLE”
“THE BACK”
“THE BACK VIEW OF THE TADPOLE, SHOWING TRANSPARENCY AND VISIBLE PIGMENTATION DETAILS”
“SIDE VIEW OF TADPOLE. NOTE THE PIGMENTATION SPREADING OVER BACK”
“VENTRAL VIEW. THE INTESTINES ARE COLORED BROWN AND THE PIGMENTATION IS YELLOW”
“THE HEART OF THE TADPOLE. THE HEART BEATS WHEN IT IS ALIVE”
“THE SECTION THROUGH THE HEAD”
“SECTION THROUGH THE GILLS”
“SAGITTAL CUT THROUGH THE TADPOLE”
“STAGE 8: METAMORPHOSIS”
“WHEN A TADPOLE UNDERGOES METAMORPHOSIS, ITS LEGS FORM, AND THE GILLS BECOME LUNGS AND EVEN THE TAIL ABSORBS FROM ITS BODY”
“THE TADPOLE UNDERGOING ITS FIRST STAGE OF METAMORPHOSIS, THE HIND LEGS”
“THE LEGS OF THE REAR ARE LONGER, AND POWERFUL”
“AT 24 DAYS THE LIMBS OF THE REAR GROW, FORMING DIGITS THAT LOOK LIKE A FOOT PADDLE. THE FRONT LEGS AREN’T EMERGED FROM THE ATRIUM, AND BEGINS TO FORM”
“AT 30 DAYS THE HIND LEGS GROW LONGER AND THE FRONT LEGS COME MORE. THE EYES ARE USUALLY SITUATED IN THE SIDES OF THE HEAD”
“BETWEEN 24-40 DAYS THE HIND LEGS GROW LONGER AND FORM WEBBED DIGITS”
“AT 40 DAYS THE PALMATE DIGITS OF THE HIND LEGS ARE FORMED”
“BETWEEN 15 TO 45 DAYS THE TADPOLE CHANGES APPEARANCES TO AN IMMATURE, FULLY METAMORPHOSED FROG”
“SIDE VIEW”
“FROM VENTRAL VIEW. A GUANOPHORE PIGMENT APPEARS ON THE ABDOMEN”
“A XENOPUS FROG”
“THE ALBINO FROG XENOPUS. NOTE THE WHITE COLORATION”