Essays on Mitosis

- The stromal cells that are found in the developing gonads of tetrapods begin from the medulla from the peritoneal wall and the cortex from inter-renal blastema or mesonephric. Hence the gonads have a dual origin.
- Spermatogenesis occurs in a syncytial complex because it involves the formation of sperm from undifferentiated cells that are first attached to rachis. Syncytial cell complex or syncytium result when cells with single nuclei fuse to for a cell with nucleus. Syncytial cell complex is vital in oogenesis in that it assists in the differentiation of cells. One other developmental model is vitellogenesis.
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Lab 1: Ethical Issue in the Movie Gattaca. The epicentre of ethical issues in the movie Gattaca is the manner in which an individual ought to be judged. Should it be by the genetic composition one is born with or by the character traits, personality attributes and ambitions chosen by an individual? Vincent is born with genetic weaknesses that could result in ailments in the future. His genetic composition denies him access to his dream job despite the fact that he achieves the required grades in school and is a strong and athletic young man. As a result, Vincent Continue reading...

Eukaryotes are organisms that made up of cells that have a have a nucleus that is bound by a membrane. They also have membrane bound organelles. Prokaryotes are organisms whose cells do not have a nucleus or any membrane-encased organelles.

Similarities

Both prokaryotes and eukaryotes have DNA as their genetic composition or material. Secondly, both cells are membrane bound. They both have ribosomes. They have nearly the same basic metabolism. Both cells have vacuoles. Lastly, the two cells both have vesicles.

Differences

Eukaryote cells have a nucleus while the prokaryote cells lack a nucleus. Eukaryotes have a true membrane binding the Continue reading...

The Process of Spermatogenesis in the Male Testis

Spermatogenesis is an intricate process that involves mitotic cell division, meiosis, and its process. The regulation of spermatogenesis involves the endocrine and the paracrine mechanisms. The spermatogenesis endocrine stimulation involves the follicle stimulating hormones (FSH) and the luteinizing hormone. The luteinizing hormone acts through the intermediary testosterone that is produced by the leydig cells in the testis. A male fertility requires the production by the testis with large number of normal spermatozoa by spermatogenesis process. There are three major steps subdivided in the process; the mitosis, meiosis, and the transformation of the round spermatid. The multiplication of spermatogonia is Continue reading...

Virtual Lab Report

Virtual Lab 1: Virtual Microscopy
A. Gauge the size of various biological components and organisms. The Virtual Microscope (copy and paste this address into a new browser window: http://learn.genetics.utah.edu/content/cells/scale/ ) can be used to make these observations. Estimate the size (length and width in microns) of
An E.Coli cell is around 0.5µm in width and around 2µm in length. A mitochondrion is around 0.5µm in width and approximately 10µm in length. A Red blood cell is around 5.5µm in width and 7.5µm in length. A virus is approximately 0.25µm in width and around Continue reading...

- While conducting research, scientists need to understand the main variables within their experiments. Define and provide an example of both an independent and dependent variable.
In any research there are mainly two variables; the independent and the dependent variables. Any scientist needs to understand the variables very well because of the following reasons. First the variable determines the type of methodology that can be used in the study. What this means is that the type or variables would determine how the whole research is carried out. For example, a variable might have qualitative or quantitative aspects that would be Continue reading...

Evolution of Sexual Reproduction

There are different forms of reproduction, which includes vegetative, asexual, sexual reproductions. Naturally, the question arises, what are the benefits of sexual reproduction in terms of fitness of a species, and how does it compare to other forms of reproduction? Logically, females reproducing asexually are more likely to have twice as many grandchildren and can increase their fitness two folds(Hurst and Peck). On the other hand, by reproducing sexually, both sexes have to invest copious amounts of time in selecting mates, making nests, bringing up offspring etc. In this paper we will try to understand the benefits and Continue reading...

Introduction/background

Saccharomyces cerevisiae is an organism that can exist either as a singled-cell organism or as pseudomycelia. It is used in many scientific studies. It is commonly known as baker’s yeast. Saccharomyces cerevisiae is widely employed in scientific studies mainly due to the following reasons: it has a sequenced genome, it is easy to maintain in the lab, researchers can easily manipulate its genetics, and it grows rapidly. Saccharomyces cerevisiae can live with two genomes (diploid, n=32) or one genome (haploid, n=16). Consequently, the organism can undergo meiotic differentiation. In diploid phase, cells of the saccharomyces cerevisiae are more Continue reading...

“Unless and until it can be proven that the unborn child is not a living entity, then its right to life, liberty, and the pursuit of happiness must be protected.” (" Reagan, “Evil Empire,” Speech Text"). Abortion, a word derived from the Latin abortus meaning to be aborted or to miscarry, refers to the premature end or termination of a pregnancy ("Latin Definition for: aborior, aboriri, abortus (ID: 171)"). Generally, a majority of women get an abortion performed before they are twelve-week pregnant, i.e. during the first-trimester. However, some women may also get an abortion performed up to twenty-four weeks Continue reading...

Cancer is the abnormal proliferation and differentiation of cells in an abnormal tissue incongruent with the growth pattern of normal cells that persists even after the stimuli that evoked the change is withdrawn. The cell cycle check points at G1, G2 and at the end of metaphase that prevent transmission of genetically damaged DNA fail to occur. Transmission of faulty DNA results in either an abnormal rate of cell division and multiplication or abnormally constituted daughter cells.
The genes affected are the normal regulatory genes including growth promoting proto-oncogenes-normal genes that are prone to becoming cancerous on mutation or Continue reading...

Cell Cycle

Introduction
Asymmetric cell division is a situation where a cell divides into parts of two cells that comprise two dissimilar cellular fates. For most part, the term applies and is usually used in referring to cells that are essentially diverse at the point of cytokinesis. Cytokinesis is the term used to describe how the cytoplasm and its organelles divide to form two separate cells. The daughter cell formed contains the same genetic material as the mother cell. This implies that individual daughter cell comprise a diverse physical makeup. This stands to convey the contrast surrounding extrinsically dissimilar cells where Continue reading...

The cell is the basic unit of all the living organisms. It contains many important structures like chromosomes, which are responsible for the genetic makeup of an organism (Wasserman 111). The cells of an organism undergo a process known as cell division. In this process, a parent cell splits into two or more daughter cells (Wasserman 111).
There are two types of cell division namely meiosis and mitosis. It is pertinent to note that, difference is that in mitosis the number of the daughter cells are two whereas, meiosis creates four daughter cells (Wasserman 120). Another thing that differentiates Continue reading...

Mitosis is an essential process in the cell cycle for the growth and development of an organism. Over the years, numerous studies have been conducted to understand the dynamics of mitosis and literatures about the process are fast accumulating. However the mechanism that is important in the vicissitudes of cellular shape during mitosis has remained unknown. Until later, a groundbreaking research on a “small ubiquitin-related modifier” (SUMO) will unravel the mystery that takes place when the cell changes its shape during mitosis.
It is a general knowledge that during the early stage of mitosis, the cell takes a round Continue reading...

Comparison and Contrast of mitosis and meiosis

One of the most essential processes that occur in living cells is cell division. This is the process in which a primary cells producer new cells by dividing into two or more parts. Cell division in living organisms usually occurs in two different ways: meiosis and mitosis.
In the 9th edition of Biology: Life on Earth by Gerald Audesirk, Theresa Audesirk and Bruce E. Byers, meiosis is defined as a kind of cell division where a diploid nucleus essentially divides twice to give rise to four haploid nuclei. Each of the four haploid nuclei contains half of the number Continue reading...

Aerobic Cell Respiration

Aerobic Cell Respiration is necessary for the respiration characteristics of life. Every living organism requires energy to use for growth and maintenance. Aerobic Cell Respiration leads to the conversion of biochemical energy into the Adenosine Tryphosphate (ADP). This occurs during catabolic metabolic reactions in which volumes of energy are released as a result of the breakdown of large molecules into small ones (Rich, P. R., 2003). This is an exothermic redox reaction which and it is through it that the living organisms manufacture energy. However, it can only occur if the body is supplied with energy rich foods such Continue reading...

Filmography

The American Science fiction film entitled Evolution starring David Chucovny, Orlando Jones, Sean William Scott and Julianne Moore was released in 2001, in which the story started when a meteor fell on earth carrying alien organisms that evolved into more complex organisms threatening to take over the earth.

Relevance to the Field of Biology

The film features several significant facts about biology and particularly in evolution. In the film, the origin of life came from one-celled organisms carried by the meteor that felon the Arizona flatlands. The organism have shown remarkable rate of evolutionary change that only happens within hours. The single-celled organism undergoes the Continue reading...

Abstract

This essay aims to explore several scientific issues: the relation between the burning of fossil fuels and its consequential unbalance of the carbon cycle and the increase of the greenhouse effect that follows it, causing a biosphere change with multiple deleterious effects, both on environments, species and life itself; understand how Darwin’s theory of Natural Selection explains the existence of different species of a being (such as lizards) in one same island; why, now in the Genetics area, a cell’s DNA is only visible during mitosis for being condensed, why “daughter cells”, in meiosis, all have unique Continue reading...

Question 1

Mitosis and meiosis are the essential processes that enhance growth of both plants and animals. The two processes serve various purposes as outline in this essay. Mitosis enhances multiplication of cells, in multcellular organism, from a single cell fused from egg and a sperm to numerous cells. Mitosis is also important in the growth of single-cell organisms, but in this case, the process helps in production since making of a new cell in a single-cell organisms mean new organism. On the other hand, serves a primary function of creating reproduction cells in the ovaries and testes.
The different between Continue reading...

- Describe the phases of meiosis II
Meiosis II has 4 phases, prophase, metaphase, anaphase, and telophase. At the end of meiosis I, microtubules move each member of the centriole pair to an opposite spindle pole in both daughter cells. During prophase II, the microtubules attach to the chromosomes causing them to recoil and shorten. During metaphase II, the microtubules, duplicated chromosomes, and motor proteins, interact in a manner that positions all the duplicated chromosomes halfway between the 2 spindle poles. During anaphase II, the connection between the 2 sister chromatids of every chromosome breaks and each of the Continue reading...

(DNA Quantification)Mitosis and Meiosis) (Genetics)
1. At 360nm, the DNA strongly absorbs light and the value generated allows easier estimation of solution concentration.
2. Contamination of RNA can easily result in an overestimation of DNA concentration due to high occurrence of RNA secondary structures.
3. The cell wall of plant cells are surrounded by a cell membrane. In this cell the DNA is located in the nucleolus and enclosed by a phospholipids membrane. In plants, the phospholipids tend to exist in the diacyl form.
4. The variations in DNA are affected by the number chromosomes in the tissue.
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Cancer and Mitotic Rate

There are basically four types of tissues in the body namely; connective tissues, epithelium, nervous tissue and muscle. Admittedly, these types of tissues have differing mitotic rates perhaps due to the type of the role they perform in the body. Even though the type of tissue that has the lowest rates cannot be accurately pinpointed, it is openly believed that epithelial tissues have the highest mitotic rates. Quite notably, neuron and muscle cells do not always undergo mitosis.
Epithelial tissues are the tissues made up of cells that form the external surfaces that cover the body. The tissues, besides Continue reading...

How an Animal Cell Survives

Although the animal cell is similar in many ways to eukaryotic as well as some few eukaryotic cells, there are strikingly large differences between them, especially the requirements for survival in various environments (Baitsell, 2008). The animal cell is one of the members of eukaryotic cell category, whose structure is quite complicated by the organelles present as well as the diverse functions they play towards the survival of the cell and the organism in general (Solomon, Berg, & Martin, 2004). The cell structure is defined by a plasma membrane that bounds a number Continue reading...

Meiosis and mitosis

Gene transfer occurs during cell division from mother cells to daughter cells. The DNA carries the genetic information transfer which it from one cell to another during cell division. Genes are located on the DNA strand that is contained in a chromosome. Mitosis and meiosis are the two types of cell division that occur during reproduction in various organisms. Mitosis involves the nucleus dividing into two identical daughter cells. Mitosis goes in hand with cytokinesis, which result in two separate daughter cells at the end of division. The process of mitosis takes place in Continue reading...