Explain why cleavage is restricted to the blastodisc in the chick embryo
ANSWER :
The meroblastic or discoidal type of cleavage occurs in the hen's egg, since, they are macrolecithal (contain large amount of yolk). Hence cleavage occuring at the animal pole stops when hit the yolk and would only restricted to the circular disc of eggs cytoplasm (blastodisc)
Explain why cleavage is restricted to the blastodisc in the chick embryo
1. What changes do you expect to see in the 72-hour chick embryo that makes it look different from a 33-hour or 48-hour chick embryo? 2. What week of human development is a 72.-96 hour chick embryo comparable to? What sensory structures are visible in the 72-hour chick embryo? 3.What sensory structures are visible in 72 hour chick embryo? 4.What changes do you expect to see in the 92-hour chick embryo that make it look different from the 72-hour chick...
Describe cleavage and gastrulation in chick embryos. Describe the role of FGFs, Cerberus, Wnt8c, nodal, and Veg1 in mesoderm induction and primitive streak formation. Also describe how BMP and noggin interact in neural induction.
Describe the progression and stages of embryo development from fertilization to an early embryo that has a fully formed neural tube. Include the following terms (at least) in your description: gastrulation, organogenesis (neurulation), zygote, cleavage, blastula, morula. Explain the functional differences of extraembryonic membranes in terrestrial vertebrates.
PLATES CHICK DEVELOPMENT 6. The 48 hr Embryo 1 2 3 Metencephalon Myelencephalon Otic vesicle Somite Foregut Amniotiefold Mesencephalon Diencephalon Optic cup Telencephalon Ventricle (heart) Somites Spinal cord
PLATE 6 48 Hour Chick Embryo 853 Diencephalon Metencephalon Myelencephalon Otic vesicle Optic cup Telencephalon Ventricle (heart) Somite Foregut Somites Amniotic fold Spinal cord Mesencephalon
PLATE 2 24 Hour Chick Embryo NAME G Record the letters and or numbers from the diagrams to the corresponding embryonic structures. Some structures may have more than one numb e r while others may have nothing Neural fold Neural be Neural plate Somite Notochord Head process Primitive ridge Primitve node Primitive groove Primitive streak Epidermal ectoderm Head mesenchyme
CHICK DEVELOPMENT 2. The 24 hr Embryo PLATE 1 Record the letters and/or numbers from the diagrams to the corresponding embryonic structures. Some structures may have more than one number letter while others may have nothing Neural fold Neural tube Neural plate Notochord Somite Head process Primitve node Primitive ridge Primitive streak Primitive groove Head mesenchyme Epidermal ectoderm Somatic mesoderm Splanchnic mesoderm
True/false, if false explain why Synergids secrete chemoattractants called LUREs, which guide pollen tubes to embryo sacs.
Question 8 In chick development, the allantois is an outgrowth of the hindgut. O True False Previous Question 9 The chick blastoderm is a hollow, spherical ball of cells and regional specification is describéd based on dorsoventral patterning. True False Next * Previous Question 10 Mutations in the homeotic genes of Drosophila can transform one body segment into another O True O False Question 11 The mouse blastocyst is essentially the same as the Xenopus blastula with a ball of...
QUESTION 4 Cell division of a fertilized egg (zygote) to form a multicelluar embryo is called: a. all of these answers are correct b. none of these answers are correct OC. coelom e. cleavage