Answer:
The study of the cell cycle focuses on mechanisms that regulate the timing and frequency of DNA duplication and cell division. As a biological concept, the cell cycle is defined as the period between successive divisions of a cell. During this period, the contents of the cell must be accurately replicated. Microscopists had known about cell division for more than one hundred years, but not until the 1950s, through the pioneering work of Alma Howard and Stephen Pelc, did they become aware that DNA replication took place only at a specific phase of the cell cycle and that this phase was clearly separated from mitosis. Howard and Pelc's work in the broad bean, Vicia faba, revealed that the cell goes through many discrete phases before and after cell division. From this understanding, scientists then identified the four characteristic phases of the cell cycle: mitosis (M), gap 1 (G1), DNA synthesis (S), and gap 2 (G2). The study of these phases, the proteins that regulate them, and the complex biochemical interactions that stop or start DNA replication and cell division (cytokinesis) are the primary concerns of cell cycle biologists.
The most significant progress in this research field came with the demonstration that specific protein complexes involving cyclins were critical for regulating the passage of cells through the cell cycle. These early observations came from biological studies of the cells of rapidly dividing fertilized frog eggs as well as mutant yeast cells that could not divide. The observations suggested that regulation of the cell cycle is conserved throughout eukaryotes, which has since proved to be the case. The mechanism of division in bacteria differs from that of eukaryotes, and the control of their cell cycle is also somewhat different, although again it is linked with DNA replication.
Although the cell cycle is a highly integrated process, distinct areas of interest within this field of study have emerged. For instance, many genes and proteins that influence the passage from one phase of the cell cycle to another have been identified. When their expression is altered by mutation or aberrant regulation, they are usually classed as oncogenes. Other proteins act to hold the cell at distinct points in the cycle (checkpoints) and are known as tumor suppressor genes. Apart from those with a clearly regulatory role, many proteins have important functions in other aspects of the cell cycle; one is replication of DNA and organelles, which is a fascinating process that includes its own repair mechanisms and self-editing. Other fields focus primarily on the mechanical processes of cell cleavage into two daughter cells at the end of mitosis and on the condensation and decondensation of chromatin.
Explanation:
Answer:
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Explanation:
Universal Model School,
90 Aba Owerri Road,
Aba,
Abia State.
April 25, 2021.
The Honorable Minister of Roads and Highways,
Federal Ministry of Roads and Highways,
Federal Secretariat,
Abuja.
Sir,
DEPLORABLE STATE OF ROADS IN SOUTH-EAST NIGERIA
It is with deep sense of urgency that I write to you regarding the deplorable state of some roads in south-east Nigeria. These roads include; Enugu-PortHarcourt expressway, Akokwa-Uga expressway and Old Umuahia road.
These roads are all strategic to sustainable of trade between south -east Nigeria and other regions of the country. The continuous neglect of these roads have led to a great downturn in the economy of south- east Nigeria.
Secondly, the poor state of these roads have hindered direct foreign investment in south- east Nigeria. Many potential investors do not bring their investments to this region of the country for fear of failure of the business due to poor state of access roads in the region.
Lastly, lack of access roads in this region have greatly enhanced capital flight out of the region. This in turn have fueled unemployment and consequent youth restiveness which currently threatens the peace of this region of the country.
I plead with you sir, to consider us in this region and quickly see to the initiation and completion of maintenance work on these affected express roads that link south- east Nigeria to other regions of the country.
Thanks in anticipation of our positive response.
Yours Faithfully,
Jude Njoku
In vocabulary exercise, we can indicate that the meaning of the words give above are as follows;
- Arrogant: This is an adjective that denotes being very self-confident.
- Boycott: This is a verb that indicates to join others in refusing to deal with someone or something. It can also be used as a noun.
- Ceremony: This is a word that implies "a formal event commemorating a particular occasion."
- Degrade: This is a verb meaning ". To inflict shame or disgrace on oneself. It can also be defined as "causing a person or people shame or dishonor."
- Integrate: This might be a verb meaning "To come together as one, especially to abolish racial segregation. Or a word that is used to meaning "the process of combing two or thing, or people or bringing together; particularly persons of different ethnic orientation."
- Supreme: This is an adjective meaning " "the highest position or rank The most important thing."
- Verdict: This is a noun word that signifies "the final decision of a trial."
<h3>What is vocabulary?</h3>
A vocabulary is a collection of words that are known to a person's native language. A vocabulary, which typically develops with age, is a helpful and important instrument for communication and information acquisition.
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Full Questions;
What are the meaning of the following words:
- Arrogant
- Boycott
- Ceremony
- Degrade
- Integrate
- Supreme
- Verdict
Answer:
The answer is letter C. Or like last week when she won the spelling bee for the millionth time. “A good thing you got ‘receive’ Squeaky, ‘cause I would have got it wrong. I completely forgot about the spelling bee.” And she’ll clutch the lace on her blouse like it was some narrow escape. Oh, brother.
Explanation:
Narrative voice is the perspective from which the story is told. In "Raymond's Run", the narrator is also a character in the story. Squeaky, whose real name is Hazel, is a smart girl who tries her best in everything she does. She is critical of others, kids and adults, and quickly judges people around her to determine if they are worth her time.
Option C shows us one of the moments where Hazel judges another character in the story, Cynthia Procter. Hazel finds it annoying when Cynthia pretends to make no effort to accomplish things. Hazel does not hide from anyone the fact that she practices and studies hard. And she knows Cynthia does the same, but won't admit to it. Cynthia acts as if she just happens to know how to play the piano, or if the spelling bee contest that she won could have been a disaster if she had gotten a certain word - one that she clearly knows how to spell. From Hazel's tone we can tell how irritated she is by such fake behavior - "Oh, brother."
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