Flashcards
BL1102-development
Cards in this deck (83)
- 1What is pattern Formationcytoplasmic determinants and inductive signals that contribute to the development of a spacial organization in which the tissues of an organism are in their characteristic place
- 2what is the name for the molecular cues that collectively influence the pattern formationpositional information
- 3what does the positional information docues that tell the cell where to position itself relative to the 3 main axis
-determines how that cell and its descendants will respond to future signals - 4what makes the drosophila a good model organism-rapid life cycle
-small size (allowing for large populations to be held)
-genetically tractible - 5anterior-posterior axishead to tail
- 6dorsal- vental axisback to belly
- 7homeotic genesregulatory genes that control pattern formation in the late embryo, larva and adult
- 8Homeosistransformation of one body region or part so that it resembles another
- 9embryonic lethal genesmutations in genes that affect the formation of segments in the body of the drosophila that would cause the death at larval or embryonic stages
- 10maternal effect genes a.k.a egg polarity genesclassed as a gene that when mutated in the mother results in the mutated phenotype of the offspring regardless of if the genotype
- 11gastrulationestablishing tissues and axis
- 12somitogenesisearly stages of bone, muscle and debris development
- 13neurulationdeveloping nervous system
- 14mesoderm, ectoderm and endoderm are what?germ layers
- 15when does implantation into the uterus wall occuronce the blastocyst hatches out of the zone pellucida- the transparent layer that surrounds the mammalian ovum
- 16what controls the formation of the body axesmaternal effect genes
-encoded by genes of the mother
a maternal effect gene is one classified that when a the mother has a mutant, this results in a mutant offspring phenotype regardless of the organisms genotype - 17give another name for the maternal effect genesegg polarity genes
- 18what does bicoid doa morphogen that determines the head structure
- 19how can the effects of bicoid be testedinjected into the body of an organisms at different intervals
-theb protein that is produced from the bicoid mRNA results in the growth of head structures where it is injected - 20what re the important events that occur during embryogenesisgastrulation
neurulation
somitogenesis - 21what are the stages of fertilisation1. the sperm comes into contact with the eggs jelly coating
2. there is a acrosomal reaction- release of hydrolytic enzymes that are released across the - 22what are the stages of embryonic developmentfertilisation
cleavage
gastrulation
organogenesis - 23what is the first stage of fertilisationsperm dissolves or penetrates any protective layer surrounding the egg to reach the plasma membrane
- 24after the sperm reaches the p.m. of the egg cells who happensmolecules on the surface of the sperm bond to receptors on the eggs surface
-this ensure tat the sperm and the egg are the same species - 25why does the surface of the egg then changeto prevent polyspermy
-this is a condition whereby multiple sperm nuclei enter the egg
-this fatally disrupt development - 26what model species has been used for much of the research on fertilisationsea urchins
-gametes easily to collect as fertilisation is external
-good general model as the same process that occurs in other vertebrates - 27describe the acrosomal reactionjelly coating of the egg exudes soluble chemicals that attract the sperm
-as soon as the head of the sperm comes into contact with the egg the acrosomal reaction occurs
-discharge of hydrolytic enzymes from the acrosome - 28what is the acrosomespecialised vesicle at the tip of the sperm that releases hydrolytic enzymes at the acrosomal reaction
- 29what do the enzymes from the acrosome dopartially digest the jelly coating
-this allows a structure within the sperm called the ACROSOMAL PROCESS to elongate and penetrate the cell - 30what does the acrosomal process dobonds with proteins that are on the plasma membrane of the egg
-ensure the correct species
lock and key design - 31what occurs after the recognition of the sperm as the same speciesthe membranes of the egg and the sperm fuse
-the sperm nucleus enter the egg cytoplasm - 32sodium channels on the membrane open at the same time as the sperm nucleus enter the cell, why is this?causes depolarisation of the egg cell
reduction in the membrane potential
this prevents additional sperm from binding with the eggs plasma membrane
depolarisation= fast act to block polyspermy - 33the depolarisation of the egg last only about a minute. this is the fast block to polyspermy what is the slow block?cortical reaction
- 34what is the cortical reactionestablished by vesicles that lie under the surface of the p.m in the area of the cytoplasm that is called the cortex
- 35what do the cortical vesicles do-after the sperm binds with the p.m the cortical granules are released into the space between the cytoplasm and the p.m
this causes the vitelline layer to move away from the outer membrane of the cell and hardens the layer into a protective fertilisation envelope - 36graphically what does this look like
- 37in mammals where does the binding of the of the sperm to the perm receptor occurzona pellucida
- 38what stage of development follow fertilisationcleavage
- 39what is the cleavage stage characterised bya rapid succession of cell divisions that characterise the cleavage stage of early development
- 40what stages of the cell cycle occur here (and which are ignored)the cell cycle at this stage consists of S and M
-dna synthesis and mitosis
the G1 and G2 phases are essentially skipped
-because there is no protein synthesis- or mass increase - 41what are the first cell divisions from the large egg calledblastomeres
- 42what is the name of the hollow ball of cells that forms after the first 5-7 cell divisionsblastula
- 43what is the hollow fluid filled cavity of the blastula calledblastocoel
- 44what differs between species during cleavagethe pattern of the cleavage
-in sea urchins and sand dollars the division pattern is uniform across the embryo
-in frog the pattern is asymmetrical with both the number of cells in different regions differing - 45why is the pattern of division asymmetricalreflects the asymmetrical distribution of the yolk
-yolk is often concentrated toward one pole of the cell - 46what is the name of the pole of the cell that the yolk is concentratedvegetal pole
- 47what is the pole that is opposite from the vegetal pole calledanimal pole
- 48what effect does the different poles have on the two cell hemispheresdifferent colours
- 49what is the indentation of the cell called as cytokinesis divides the cell in halfcleavage furrow
- 50what are the relative sizes of the cells that are formed in the vegetal and animal polessmall cells in the animal pole
large cells in the animal pole - 51what is mesoblastic divisiondivision occurs only in the region of the egg that lacks the yolk can divide due to the volume of yolk
- 52what is holoblastic divisioncleavage furrow can pass through the yolk
- 53describe what the cell of the newly fertilised egg doesn't have-doesnt have enough DNA to produce the amount of RNA needed for protein synthesis
-initial development is carried out using the RNA and proteins deposited during oogenesis - 54what is morphogenesisthe cellular and tissue based processes by which the animal body takes shape
- 55what stage of development follow cleavagegastrulation
- 56what occurs during gastrulationcells that are near the surface of the blastula move to an interior location
-cell layers are established
-primative digestive tube is formed - 57define gastrulationdramatic recognition of the hollow blastula into a 2 or 3 layered embryo called the GASTRULA
- 58what are the collective names of the cell layers that are formed during gastrulationgerm layers
- 59what are the inner and outer germ layers calledectoderm- forms the outer layer
endoderm- lines the embryonic digestive compartment or tract - 60vertebrates have 3 germs layers- what is the term used to describe thistriploderms
- 61what is the name of the third germ layer in vertebratesmesoderm
- 62what is the name of the narrow blind ended tube that is formed by the extensive rearrangement of cells during gastrulationarchenteron
- 63what does the open end of the archentron become? what is the name of this?anus
-blastopore - 64what is the name of organisms who's mouth forms after the anusdeuterosomes
- 65draw the process of gastrulation
- 66what follows gastrulation?region of the 3 germ layer develop into the rudiments of organs
-often the cells from 2 or 3 of the layer go into making a single organ
interactions between the cells of different layers helping to specify the cell fate - 67what is neuralationthe early steps in the development and formation of the brain and spinal cord
- 68what is the notochorda rod the extends along the dorsal side of the chordate embryo
- 69how is the notochord formedsignalling molecules from the mesodermal cells and other tissues cause the ectoderm above the notochord to become the neural plate
- 70what is inductiona process by which the a group of cells influences the development of another group of cells through close range interactions
signal come from neighbouring cels or the environment - 71draw the notochord within a developing cell
- 72what happens after the neural plate is formedthe cells change shape- curving the structure inward
-neural plate rolls itself into a neural tube
this runs along the anterior posterior axis - 73what does the neural tube become in developmentthe brain and spinal cord
-the notochord disappears after birth- becomes portions of the disks in the adult spine - 74what condition is as an effect of imperfect neurulationspina bifida
portion of the tube fails to develop or close properly
-leaving in an opening in the spinal column
-causing nerve damage
-opening can be repaired after birth but the resulting nerve damage persists
varying degrees of leg paralysis - 75what is the name for programmed cell deathapoptosis
- 76why might whole tissue cease to develop, die or be englufed by the surrounding cellswhen the groups of birds, , amphibians began to diverge
-the developmental body plan was already in place
-not counteracted by evolution
-differences that there are between the ancestor and the modern day arise through modification
e.g. webbing of digits - 77what is determinationrefers to the process by which a cell or group of cells become committed to a particular fate
- 78what is differentiationrefers to the resulting specialisation in structure and function
- 79what is fate mappingdiagrams showing the structures arising from each region of the embryo
- 80how can cell fate be followed experimentallytechniques that allow researchers to mark individual blastomere cells during cleavage
-follow the marker - 81what model organism has been used in fate mapping experimentsc. elegans
- 82describe c. elegans-roundworm
-1mm in length
-simple transparent body
maturity reacher in 3 and a half days - 83what are the germ cellscell that turn into eggs and sperm
-in the new embryo the p granules can be seen throughout the organisms
-the p granules are asymmetrically partitioned -move to the posterior end of the organisms
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- bl1102 biology Flashcards on BL1102-development , created by Samantha Bruce on 30/04/2018.
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