Animal Physiology - Lecture 5 Flashcards
(39 cards)
Development is a series of progressive change in .. and .. during an organisms life cycle
form, function
Most intense period of development is … -> …
fertilisation, maturity
fertilisation is the formation of .. and .. to give zygote
egg, sperm
cleavage is the division of cells to form the ..
blastula
- occurs after fertilisation
gastrulation is the formation of … .. and .. ..
it’s where the blastula is transformed into a proper …
tissue layers, body axis
embryo
-can be oral or aboral dependant on speces
organogenesis is the formation of ..
organs
morphogenesis is the mechanism of .. shape formation
body
the cytoplasm and mitochondria of a zygote comes from the ..
egg
-as sperm organelles degenerate by this time
the nucleus of the egg is within the … hemisphere
animal
nutrients within an egg accumulate in the .. hemisphere
vegetal
in amphibians the vegetal hemisphere is …, while the animal hemisphere is .. and has a surface layer
unpigmented, opaque
sperm enters a cell at the … hemisphere, causing the … to rotate and expose the ‘grey crescent’ opposite the site of fertilisation
animal, cortex (outer layer)
proteins in the grey crescent control what .. cells will take
form
blastomeres are produced during cell .. and are essential in … formation
when formed from a morulla the .. has a … in the middle
clevage, blastula
blastula, blastocoel
in cleavage, cells divide yet the overall mass of cells .. change
doesn’t
in complete clevage, the whole cel divides, without a yolk all cells are .. in size
however with a yolk, the yolk … the clevage and cells divide ..
equal
impedes, asymmetrically
in incomplete discoidal clevage, lots of yolk .. the clevage furrows from penetrating the yolk
this causes a … to give rise to the embryo and its associated membranes, the yolk underneath provides .. for the growing envelope
prevents
blastodisc, nutrients
-discoidal incomplete clevage happens in birds
Superficial incomplete clevage results as the nucleus divides but .. does not follow
chromosomes are split and form new .., which then imigrate to the edges of the cell and the plasma membrane then grows .. from the edges, partitioning the nuclei into individual cells
cytokinesis
nuclei
inwards
in radial clevage, mitotic spindles form at right angles or parallel to …-… axis
animal, vegetal
in spiral clevage mitotic spindles form at .. angles to the .. axis
oblique, vegetal
in rotational clevage, the first division is … to vegetal-animal axis, the second division is at a .. angle and the third is at a .. angle to that
parallel
right,right
totipotency refers to cells being .., at determination however these cells then become .. in roles
undifferentiated, fixed
in gastrulation the blastula is separated into three tissue layers, the .., .. and …
endoderm, exoderm, mesoderm
the endoderm is the innermost layer and produces the …, .. and .. tract
digestive, circulatory, respiratory