NPB123 Midterm 1
Where do gametes arise? Meiosis of germ cells
1. Contact and Recognition
2. Regulation of Sperm Entry
Four basic steps of fertilization
3. Fusion of Pronuclei
4. Activation of egg metabolism
What does the sperm develop in acrosomal filament, extension of acrosome to fuse with vitelline envelope
marine invertebrates?
What is the acrosome activated by contact with zona pellucida
in mammals?
What are the two ways to prevent fast block and slow block
polyspermy?
Increased membrane potential caused by release of Ca2+ inside
Fast Block
egg and closing of Na+ channels
Cortical Granule Reaction caused by Ca2+ triggering the cortical
Slow Block
granules in the cortex to release enzymes preventing
polyspermy
What is the ploidy of germ cells? 2n, 1n, 1n, 2n
Gametes? Pronuclei? Zygote?
How do the egg and sperm Sperm centriole acts as microtubule brining pronuclei to center for fusion
pronuclei fuse?
How does egg activation occur? Ca2+ levels activates egg
differentiation of fertilized eggs into many cell types and
Embryogenesis
construction of functionally integrated organs
Amniote vertebrate whose embryo or fetus is enclosed by a thin, tough membranous
sac
Anamniote a vertebrate that lacks an amniotic membrane around the embryo
Cell potency a cell's ability to differentiate into other cell types
, Totipotent Can develop into all types of cells
Pluripotent Can develop into multiple types, but not all of cells
When are embryonic stem cells Tot: cleavage stages, embryo and
totipotent vs pluripotent? extraembryonic tissue Plur: blastocyst, only
embryonic
What is cell fate determined by? environment and differential gene expression
the process in which a gastrula develops from a blastula by the
Gastrulation
inward migration of cells and establishment of 3 germ layers
outermost germ layer; develops skin, sensory system, brain and
Ectoderm
spinal cord, neural crest cells
Mesoderm middle germ layer; develops into muscles, blood, kidneys, urogenital tract
innermost germ layer; develops into digestive tract, and anything
Endoderm
not mesodermally derived
What does the endoderm replace in hypoblast
amniotes?
Alimentary canal digestive tube that extends from the mouth to the anus
Allantois collects liquid waste and exchanges gas from embryo in amniotes
Oral Plate anterior gut fuses with ectoderm to form
Androgen hormone that promotes masculine characteristics
Estrogen hormone that promotes feminine characteristics
XX gonads ovaries and mullerian ducts
Xy gonads testis and wolffian ducts
What does the wolffian duct vas deferens
become?
Sertoli cells secrete anti mullerian hormone, become testi cords (seminiferous tubules)
SRY gene sufficient to induce cis-male phenotype, activates SOX9
SOX9 gonads necessary and sufficient for development of male genitalia
What does the mullerian duct oviducts, uterus, cervix, vagina
become?
follicles surround germ cells and secrete estrogen
similar physical features in organisms that share a common
Structural homology
ancestor, but the features serve completely different functions
phylotypic stage stage in embryonic development in animals -embryos of all vertebrates look
similar
Where do neural crest cells arise dorsal neural tube
from?
Epithelial to Mesenchymal Transition cells become less sticky and more free to move
What neural crest cells are the cranial, sacral
Where do gametes arise? Meiosis of germ cells
1. Contact and Recognition
2. Regulation of Sperm Entry
Four basic steps of fertilization
3. Fusion of Pronuclei
4. Activation of egg metabolism
What does the sperm develop in acrosomal filament, extension of acrosome to fuse with vitelline envelope
marine invertebrates?
What is the acrosome activated by contact with zona pellucida
in mammals?
What are the two ways to prevent fast block and slow block
polyspermy?
Increased membrane potential caused by release of Ca2+ inside
Fast Block
egg and closing of Na+ channels
Cortical Granule Reaction caused by Ca2+ triggering the cortical
Slow Block
granules in the cortex to release enzymes preventing
polyspermy
What is the ploidy of germ cells? 2n, 1n, 1n, 2n
Gametes? Pronuclei? Zygote?
How do the egg and sperm Sperm centriole acts as microtubule brining pronuclei to center for fusion
pronuclei fuse?
How does egg activation occur? Ca2+ levels activates egg
differentiation of fertilized eggs into many cell types and
Embryogenesis
construction of functionally integrated organs
Amniote vertebrate whose embryo or fetus is enclosed by a thin, tough membranous
sac
Anamniote a vertebrate that lacks an amniotic membrane around the embryo
Cell potency a cell's ability to differentiate into other cell types
, Totipotent Can develop into all types of cells
Pluripotent Can develop into multiple types, but not all of cells
When are embryonic stem cells Tot: cleavage stages, embryo and
totipotent vs pluripotent? extraembryonic tissue Plur: blastocyst, only
embryonic
What is cell fate determined by? environment and differential gene expression
the process in which a gastrula develops from a blastula by the
Gastrulation
inward migration of cells and establishment of 3 germ layers
outermost germ layer; develops skin, sensory system, brain and
Ectoderm
spinal cord, neural crest cells
Mesoderm middle germ layer; develops into muscles, blood, kidneys, urogenital tract
innermost germ layer; develops into digestive tract, and anything
Endoderm
not mesodermally derived
What does the endoderm replace in hypoblast
amniotes?
Alimentary canal digestive tube that extends from the mouth to the anus
Allantois collects liquid waste and exchanges gas from embryo in amniotes
Oral Plate anterior gut fuses with ectoderm to form
Androgen hormone that promotes masculine characteristics
Estrogen hormone that promotes feminine characteristics
XX gonads ovaries and mullerian ducts
Xy gonads testis and wolffian ducts
What does the wolffian duct vas deferens
become?
Sertoli cells secrete anti mullerian hormone, become testi cords (seminiferous tubules)
SRY gene sufficient to induce cis-male phenotype, activates SOX9
SOX9 gonads necessary and sufficient for development of male genitalia
What does the mullerian duct oviducts, uterus, cervix, vagina
become?
follicles surround germ cells and secrete estrogen
similar physical features in organisms that share a common
Structural homology
ancestor, but the features serve completely different functions
phylotypic stage stage in embryonic development in animals -embryos of all vertebrates look
similar
Where do neural crest cells arise dorsal neural tube
from?
Epithelial to Mesenchymal Transition cells become less sticky and more free to move
What neural crest cells are the cranial, sacral
