Virtual Lab #3 - Assignment Example

BIO 113 Virtual Lab #3 Population Biology Table I: Day P. caudatum alone, cells/mL P. aurelia alone, cells/mL P. caudatum mixed, cells/mL P. aurelia mixed, cells/mL02222212814104285222346488622688609618821056961092125698292145696096166098094Journal Questions:1. Make a hypothesis about how you think the two species of Paramecium will grow alone and how they will grow when they are grown together.The two species of Paramecium will survive and increase in number when grown alone in the separate environments and attain the carrying capacity in both cases.

However, when the two species are grown together the number of one species of Paramecium will diminish and become extinct as the other specie attains a constant number after reaching a level that the available resource can support. 2. Explain how you tested your hypothesis.Three environments were created, the first one with Paramecium caudatum alone, the second with P. aurelia alone and the third with both species to assess their intterraction in the same environment. The two species were grown in the medium separately to determine their growth patterns by counting the number of Paramecium after a given period.

The two species were then grown in the same medium to assess the competition for food between themselves and whether the principle of competitive exclusion existed between the species. This was done by counting the number of both Paramecium species in the same environment after the given time interval.3. On what day did the Paramecium caudatum population reach the carrying capacity of the environment when it was grown alone? How do you know?On the 8th day Paramecium caudatum attained its maximum capacity of 60 species .

The prove for this observation is that the population attained on this day did not increase in the subsequent days (repeated in subsequent days). In fact, the population decreased to 56 cells on 10th day and remained stable until the 16th day when it reached 60 cells again. These observations illustrates that the population attained the maximum that the available food resource can support (carying capacity) because the amount of food available could only support that or fewer number.4. On what day did the Paramecium aurelia population reach the carrying capacity of the environment?

How do you know?On the 12th day Paramecium aurelia attained the maximum cell population of 98 species. The population attained on this day was the maximum and did not increase further in the subsequent days of growth (number was repeated), in fact, on the 14th day it decreased to 96 cells and later attained 98 on the 16th day, which illustrates that the population attained the maximum of 98 cells because the amount of food available could only support that number or fewer than that number of cells.5. Explain the differences in the population growth patterns of the two Paramecium species.

What does this tell you about how Paramecium aurelia uses available resources?The two species exhibited major differences in their growth patterns over the same duration investigated. Growing the species in separate test tubes shows that Paramecium aurelia exhibited almost twice the rate of growth as that of Paramecium caudatum when conditions provided for their growth are the same. This shows that P. aurelia has better capabilities of utilising available resources and overcoming growth limitations like accumulation of toxins than P.

caudatum when grown in the same medium or in different environments. Besides, this could mean that one specie P. caudatum uses more food resources as one specie of P. aurelia hence the discrepancy in the number of cells when placed in the environment with similar conditions. The evidence for this observation is seen in the mixed slide. Besides, Therefore, the carrying capacity of P. aurelia is higher than that of P. caudatum 6. Describe what happened when the Paramecium populations were mixed in the same test tube.

Do the results support the principle of competitive exclusion?When the species were in the same test tube, Paramecium aurelia grew at a fater rate than P. caudatum. In fact, P. caudatum grew at the lowest rate than when grown alone. This shows that P. aurelia outcompetes the P. caudatum for the available food as evidenced by its increasing number in the subsequent days while P. caudatum decreases. Besides, another explanation relates to the toxins produced by P. Aurelia, which may play a role in the elimination of P. caudatum. The observation show that P.

aurelia has better strategies of utlisation available resources like food, and resistance to accumulated toxins than the P. Caudatum.The principle of competition exclusion ascribes that under constant ecological factors, two species that competes for similar resource would not coexist. The mixing of the Paramecium species exhibited a perfect competitive exclusion because P. aurelia attained the highest count while P caudatum count became zero (died off). This show that one specie stayed at the highest count while the other died off because it could not compete for the available resource (it lacked resources to survive).

In fact, on the 16th day, the numebr of P. caudatum becomes extinct while P. aurelia attains the carrying capacity for thr mixed species, thereby supporting the principle of competitive exclusion.7. Explain how this experiment demonstrates that no two species can occupy the same niche.When two species occupies a similar niche, they compete for the same available resources as well as for the biotic and abiotic factors. Given that these species have different genomic composition, one specie is likely to possess superior way of obtaining the available resources more easily than the other.

Therefore, natural selection will take its course to drive the other specie to extinction. In fact, if extinction does not take place, the specie must develop capabilities of utilising resources that would not be used by the other specie through niche extension (which did not happen in this experiment). for instance, the experiment proves that mixing of the two species in the same test tube show that P. aurelia outgrows and outcompetes P. caudatum because the number of the latter keeps decreasing and diminishes out as opposed to when cultured alone.

Contrary, the number of P. aurelia increased with time and eventually attains the carrying capacity once the number of P. caudatum is zero because it lacked resources. This show that the two species cannot exist in the same niche because the less dominant specie becomes extinct with time as it cannot compete for the available resources. Post-laboratory Questions:1. Paramecia possess:a. A nucleusb. Flagellac. A contractile vacuoled. A and Ce. All of the above2. The organisms used in this experiment belong to which domain of life?a. Bacteriab. Archaeac. Eukarya3.

What served as the food for the paramecia in this experiment?a. Riceb. Oatsc. Bacteriad. Nothing, they are photosynthetic4. Which of the following can influence the carrying capacity of a population?a. Availability of foodb. Availability of waterc. Competitiond. Build up of toxinse. All of the above5. Which type of competition would be observed between organisms within the P. caudatum culture?a. Interspecificb. Intraspecificc. There would be no competition, they are of the same species6. Which culture reached its carrying capacity the fastest in this experiment?a. P.

caudatum, aloneb. P. aurelia, alonec. P. aurelia, mixed7. You have counted 30 organisms in your culture on Day 4. The concentration of organisms in this culture is:a. 15 cells/mLb. 30 cells/mLc. 60 cells/mLd. 90 cells/mL8. Based upon your data, which culture experienced the greatest rate of exponential growth?a. P. caudatum, aloneb. P. aurelia, alonec. P. caudatum, mixedd. P. aurelia, alone9. Based upon the data, which organism appeared more efficient at using its resources?a. P. caudatumb. P. aurelia10.

In a repeat of this experiment, you found that on Days 10-16 the number of individuals in the P. caudatum, mixed culture began to gradually rise. A possible explanation for this is:a. There was insufficient food in the cultureb. The temperature warmed enough to allow for more growthc. A genetic variant of the original population began to experience growth due to its use of a different food (bacterium) sourced. None of the above could lead to this scenario