Bio Term Essay

C-Fern plants are a strain of Ceratopteris richardii and have a rapid reproductive cycle, making them perfect subjects in lab to be tested and observed on population genetics. Population genetics is the study of genetic variation and allelic frequencies on a specific group over an amount of time. It is a great way to predict future genetic information on more than just the C-Ferns. In this experiment, two different generations for gametophytes and sporophytes of C-Ferns were observed and counted for the amount of wild type and polka dot mutant individuals within a sample and a population. The overall results demonstrated a 1:1 ratio of mutant to wild type in the F1 gametophyte generation for both the sample and population, which was expected. The F1 sporophyte generation demonstrated a 1:1 ratio of mutant to wild type in the sample and a 2:1 ratio of mutant to wild type in the population. A 3:1 ratio of mutant to wild type was expected in the sporophytes. It was concluded that the polka dot mutant is recessive in sporophytes and demonstrates random fertilization in the diploid stage, but not in gametophytes. This process of population genetics in C-Ferns can be extremely beneficial in other organisms, such as humans. Population genetics could be a tool in medicine in determining human

Exercise 3A is a study of mitosis. You will simulate the stages of mitosis by using chromosome models.You will use prepared slides of onion root tips to study plant mitosis and to calculate the relative duration of the phases of mitosis in the meristem of root tissue. Prepared slides of the whitefish blastula will be used to study mitosis in animal cells and to compare animal mitosis and plant mitosis.

Out of a total from 26 sequences only 6 were made up of 4‘s while 20 were composed of different structures of 2‘s. This tells us that 77% of the asci showed crossing over while 23% did not.

Caenorhabditis elegans, a type of free-living nematode that is found in soil, is the subject matter for this experiment (Marsh). C. elegans allow for an exceptional model organism because it is easily raised in the laboratory setting, it reproduces rapidly, has a short life cycle of 3 days where it develops from egg to adult worm, only 1.3mm in length, and although only having 959 somatic cells, it shares many characteristics with other multicellular organisms like having organs and a nervous system (Kaletta). These nematodes can either be a self-fertilizing hermaphrodite where each animal produces both sperm and egg, or they can be males that will mate with the hermaphrodites (Brenner). When a hermaphrodite self-fertilizes, the chance of having a male being produced is extremely low at just 0.1%, however, when a hermaphrodite is fertilized by a male, the ratio of males to hermaphrodites is generally equal making it 1:1 (Altun).

I judge the credibility of the item to be: I judge the credibility of this article to be accurate.

_____ In swine, when a pure-breeding red is crossed with a pure-breeding white the F1 are all red. However, the F2 shows 9 red, 1 white and 6 of a new color, sandy. The Sandy phenotype is most likely determined by

Charlene Forest is an associate professor in the Biology department at Brooklyn College, who dedicates her research in to trying to understand the mechanism behind the process of fertilization in algae, as well as what controls expression of gamete-specific genes. To do so, she must understand how sperm and egg gametes first recognize and then fuse with each other. Thus, in order to find what causes the fusion of these gametes, Forest’s lab is cloning genes that prevent the fusion of sperm and egg gametes. She hopes that her research on the fertilization process in algae will help understand the fertilization process in other organisms, particularly humans.

The basic plant life cycle with alternation of generations is modified in angiosperms by the change of haploid (n) and diploid (2n) generations, which take turns making each other.

Daphnia reproduce sexually and asexually. The Asexual way they reproduce is called Parthenogenesis. Parthenogenesis occurs in the Summer time. This happens when the population is low and conditions are favorable to the young. The mother molts to increases her size and stores 2 – 20 eggs in the Crood

We hypothesis that Scolopocryptops sexspinosus absorbs much of its water content through direct contact with a source of ground or rain water, therefore there will be similarities

Haldane 's rule is an observation in the early stage of speciation, it was formulated in 1922 by the British evolutionary biologist J.B.S. Haldane. The rule states that in a species hybrid if only one gender is inviable or sterile, this is more likely to affect the heterogametic sex, which is the sex that has two different rather than two identical sex chromosomes. Haldane 's rule applies to the vast majority of heterogametic organisms observed. It includes when two species, where secondary contact in an area of sympatry results in incomplete reproductive isolation, form hybrids after allopatric speciation has occurred. As Haldane’s Rules encompasses a generality for the evolution of reproductive isolation, at least in gonochoric animals, it holds a central position in speciation research, especially since the mid-1980s, when studies of speciation genes began to blossom (Sun et al., 2004).

The Origin of Life When considering the many theories involving “How life began” You must not consider a few main theories but a few main theory groups. Because there are literally hundreds of theories on this subject which can be grouped in to three main categories and then in to various sub categories. 1) Creation science This consists of about twelve theories that are based on the book Genesis all slightly varying in their interpretation. These can be split into two main groups, New and Old earth creationists.

Disparity in cost of reproduction has lead sexually reproducing plants to develop different methods of dealing with the cost of reproduction, an example of this is sequential hermaphroditism, where an individual can change sex at one point in their life. Jack in the pulpit, Arisaema triphyllum, is a sexually dimorphic plant that exhibits sequential hermaphroditism, this study looks to see if female A. triphyllum will exhibit the largest leaf sizes due to their need to meet higher costs of reproduction. Forty individuals were surveyed for sex and largest leaf length per area for 7 different locations within Morningside ravine. Individuals were analyzed for mean leaf length per sex, and means were analyzed for significance with a 1-way ANOVA followed by a tukey test. All means were found to be significantly different from each other with the mean of females leaves the largest, followed by males, and asexual individuals were the smallest. Female individuals of A. triphyllum had the largest leaf sizes to compensate for their elevated costs of reproduction. The size advantage model explains that that female A. triphyllum will have the largest leaves because female individuals are able to best meet the costs of reproduction at larger sizes.

There are times where specialists require some assistance in discovering the particular issues and states of their patients. At the point when specialists need to be certain about what their patients' conditions are, they take body liquid or tissue tests from them and forward these examples to the pathology advisors.

Hence, gonochoric bilaterians with separate sexes in different individuals eventually became more ubiquitous than hermaphroditic bilaterians. Yet, hermaphroditism still occurs in certain bilaterians as this condition provides them with a higher chance of reproduction and passing on genes to their offspring before death, especially if finding suitable mates could pose a challenge due to population density, size and mobility constraints, and environmental conditions of their habitats. Thus, this essay aims to discuss three reasons for the occurrence of the hermaphroditic condition amongst certain bilaterians (using examples of animals from phyla Mollusca, Annelida and Platyhelminthes), and explain with evaluation the possible roles that hermaphroditism provides. Table 1 gives a brief description on the hermaphroditic reproduction process amongst the bilateria, and would be referred to in