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The first stage of prophase I is the leptotene stage, also known as leptonema, from Greek words meaning " thin threads ". In this stage of prophase I, individual chromosomes — each consisting of two sister chromatids — change from the diffuse state they exist in during the cell's period of growth and gene expression, and condense into visible strands within the nucleus.
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first and stage
The life history of the alkali bee is similar to that of Andrena, but the first activity of the adults does not take place until summer, and the individuals hibernate in the prepupal stage.
The first stage of translation after glossary lookup is structural analysis of the input text.
Although it is not possible to sunder old and new in this era, I shall consider in the present chapter primarily the first decades of the eighth century and shall interpret them as an apogee of the first stage of Greek civilization.
The first stage of operation has centered on the literature imaging of critical or summarizing tabulations such as the Barker Index.
The luminous gain of a single stage with Af ( flux gain ) is, to a first approximation, given by the product of the photocathode sensitivity S ( amp / lumen ), the anode potential V ( volts ), and the phosphor conversion efficiency P ( lumen/watt ).
It is obvious that the careful choice of photocathode which maximizes Af for a given input E ( in the case of the second stage, for the first phosphor screen emission ) is very important.
He recognized that whatever transformation may be effected in the first stage of an R-stage process, the remaining stages must use an optimal Af-stage policy with respect to the state resulting from the first stage, if there is to be any chance of optimizing the complete process.
Moreover, by systematically varying the operating conditions in the first stage and always using the optimal Af-stage policy for the remaining stages, we shall eventually find the optimal policy for all R stages.
For any choice of admissible policy Af in the first stage, the state of the stream leaving this stage is given by Af.
If we consider a process in which the outcome of one stage is known before passage to the next, then the principle of optimality shows that the policy in subsequent stages should be optimal with respect to the outcome of the first.
Thus, typically, the first stage of a Communist takeover is to `` neutralize '' a country.
During the first stage of the plague outbreak, Paneloux preaches a sermon at the cathedral.
Assuming no loss of time when moving a car from one station to another, the longest stage on the assembly line determines the throughput ( 20 minutes for the engine installation ) so a car can be produced every 20 minutes, once the first car taking 35 minutes has been produced.
* 1871 – The first stage of the Brill Tramway opened.
The excavators discovered the final stage of the Temple of Aphrodite, also known as Aphrodisias, which dates approximately to the first century BC.
* 1944 – The 1st Air Commando Group using Sikorsky R-4 helicopters stage the first use of helicopters in combat with CSAR operations in the China-Burma-India theater.
NASA later confirmed the object to be a piece of the first stage of the Saturn V rocket that launched Apollo 16 into space.
Ayckbourn joined Wolfit on tour to the Edinburgh Festival Fringe as an acting assistant stage manager ( meaning a role that involved both acting and stage management ) for three weeks, with his first role on the professional stage being various parts in The Strong are Lonely by Fritz Hochwälder .< ref name = acting >
first and prophase
Actually, the first four stages of prophase I in many respects correspond to the G < sub > 2 </ sub > phase of mitotic cell cycle.
Meiosis generates genetic diversity in two ways: ( 1 ) independent alignment and subsequent separation of homologous chromosome pairs during the first meiotic division allows a random and independent selection of each chromosome segregates into each gamete ; and ( 2 ) physical exchange of homologous chromosomal regions by homologous recombination during prophase I results in new combinations of DNA within chromosomes.
However, since mitosis is the division of the nucleus, prophase is actually the first stage.
After the successful completion of the G < sub > 2 </ sub > checkpoint, the final checkpoint in interphase, the cell proceeds to prophase, or in plants to preprophase, which is the first stage of mitosis.
In week 11-12 post coitus the first meiotic division begins ( before birth for most mammals ) and remains arrested in prophase I from a few days to many years depending on the species.
G < sub > 2 </ sub > phase ends with the onset of prophase, the first phase of mitosis in which the cell ’ s chromatin condenses into chromosomes.
This " tripartite structure " is seen during the pachytene stage of the first meiotic prophase, both in males and in females during gametogenesis.
However, primary oocytes are arrested in prophase 1 of the first meiosis and remain in that arrested stage until puberty begins in the female adult.
Because it is hypothesized that oogonia either degenerate or differentiate into primary oocytes which enter oogenesis and are halted in prophase I of the first meiosis post pardem, it is concluded that adult mammalian females lack a population of germ cells that are able to renew or regenerate.
first and I
He stopped, embarrassed, and Morgan said, `` I understand that, but I don't savvy why you'd go off and leave your jobs in the first place ''.
At first I thought he had missed.
No one was behind it, but in the rear wall of the office I noticed, for the first time, a door which had been left partially open.
Gracias '', I hollered, my first long swallow filling me with confidence and immediately doubling the size of my Spanish vocabulary.
I ducked just as the first strand broke somewhere down the line and came whipping over the sideboards.
And that is the way I first saw her when my Uncle brought her into his antique store.
At first, I thought he was out of his head, talking wildly like this.
Hell, I gave him the first decent job he ever had, six, seven -- how many years ago was it, Rob ''??
`` Bastards '', he would say, `` all I did was put a beat to that Vivaldi stuff, and the first chair clobbered me ''!!
When I mentioned that for my first long voyage I did not even have the money for the return fare, but had trusted to luck that I would earn a sufficient amount, the young people looked at me doubtingly.
His first inaugural address speaks of `` my country whose voice I can never hear but with veneration and love ''.
But first I want to quote him on the relationship that he found between religion and politics in this country and what happened to it.
and, `` I do think that families are the most beautiful things in all the world '', burst out Jo some five hundred pages later in that popular story of the March family, which had first appeared when Henrietta was eight ; ;
When I take over Taliesin, the first thing I'll do is fire you ''.
If `` Jack the Courtier '' is really to be taken as Swift, the following remark is obviously Steele's comment on Swift's change of parties and its effect on their friendship: `` I assure you, dear Jack, when I first found out such an Allay in you, as makes you of so malleable a Constitution, that you may be worked into any Form an Artificer pleases, I foresaw I should not enjoy your Favour much longer ''.
I had had difficulties from the very first day.
As a groundwork for the proposal I give some attention to the first task enumerated above, the clarification of goal.
For this reason, then I want to describe, first, two examples of the puritanical attacks: Stephen Gosson's The School Of Abuse, 1579, and his later Playes Confuted, published in 1582.
The first time I went there he asked me to bring him water from Flagler's well -- water that reminded him of his first days in the mountains -- and before I came the next time I filled a five-gallon jug for him and brought it to the hospital.
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