Please, please answer the question. And honestly, I would much prefer if you typ
ID: 218378 • Letter: P
Question
Please, please answer the question. And honestly, I would much prefer if you type the answer down. Thank you!
I don't know how else I can elaborate this developmental biology problem. I'm sorry.
8. We have been seeing Bone Morphogenic Protein (BMP) as a major player in development for quite a while now. We have also come to realize the importance of concentration gradients of various factors in determining cell fates. With respect to derivatives of the ectodermal germ layer, list the following: Four differentiated cell or tissue types whose predecessors were exposed to high levels of BMP. Three differentiated cell or tissue types whose predecessors were exposed to moderate levels of BMP Three differentiated cell or tissue types whose predecessors were exposed to low levels of BMPExplanation / Answer
There are 3 germ layers : Ectoderm, Mesoderm and Endoderm.
The ectoderm is differentiated into 3 parts: 1) Surface ectoderm, 2) Neurectoderm and 3) Neural Crest. It has been demonstrated that a gradient of BMP patterns the ectoderm during the gastrula stages, which lead to differentiated cell or tissue types of these 3 layers. The levels of BMP activity and the derivatives of these 3 layers are listed in the table below.
For the sake of the answer, the expected number of differentiated tissue types are indicated in bold, for each layer.
Epidermis, Hair, Nails, Enamel of teeth, Internal and external ear, Lens, Anterior pituitary gland, parotid
The neuroectoderm transforms into neural plate, neural tube, and neural groove (associated with neural folds).
Neural tube further differentiates into : Central Nervous System (Brain and Spinal Cord), Retina, Optic Nerve, Pineal gland, Neurohypophysis, Astrocytes, Oligodendrocytes, Posterior pituitary gland.
Surface Ectoderm Neural Crest NeurectodermEpidermis, Hair, Nails, Enamel of teeth, Internal and external ear, Lens, Anterior pituitary gland, parotid
Adrenal medulla, Sensory and Autonomic ganglia, Schwann cells, pigment cells in the skin, Meninges, Pharyngeal arch cartilage, Odontoblasts, Parafollicular C cells in thyroid, endocardial cushion, aortic-pulmonary septum.The neuroectoderm transforms into neural plate, neural tube, and neural groove (associated with neural folds).
Neural tube further differentiates into : Central Nervous System (Brain and Spinal Cord), Retina, Optic Nerve, Pineal gland, Neurohypophysis, Astrocytes, Oligodendrocytes, Posterior pituitary gland.
Differentiation triggered by high levels of BMP activity Differentiation triggered by moderate or intermediate levels of BMP activity Differentiation triggered by low or no BMP activity