Biology
Ecology
1. Would you expect endangered species to be more frequently generalists or specialists? Explain your answer.
An endangered species is more likely to be a generalist. Although they can adapt to various factors within their environment they are forced to compete with other species that can adapt as well. More frequently they are the invasive species.
2. How does temperature affect water availability in an ecosystem?
In warmer temperatures, there is an increase in evaporation of water into the atmosphere. This increase evaporation causes moisture and can leads to a lot of rain, which changes in the soil pH levels, the water level and salinity as well as the nutrients and toxicity concentrations. These are all chemical factors that will affect an organisms living in a particular ecosystem.
3. Choose a species and describe some adaptations that species developed that allow them to survive in their native habitat.
According to the black bear biology, “like all animals, black bears exhibit specific adaptations that help them survive in their habitat.” Black bears are scientifically classified as Carnivora, which is the order of eutherian mammals. They are also considered to be omnivores with their diets varying depending on location. They mostly live in large forested areas, but may leave the forest in search of food. The Black bear has huge body structure with thick legs, enormous shoulders, a short back and canine teeth. This kind of teeth is designed for strength and power when catching and devouring their prey. Although they can move at a fast pace over short distances, with maximum speeds of up to 30 miles per hour, black bears quickly overheat due to their size. Usually the plants they consume make up approximately 95% of their diet, and swiftly move through the bear’s digestive systems. Since most of the plant fiber is undigested, fewer nutrients are removed. Black bears tend to solve this situation by eating huge amount of food, before it hibernates. They also selectively search for easily digestible plants with concentrated nutrients of nuts and fruits. The black bear has canine teeth and detached lips. This kind of adaptation helps them to yank berries from trees and shrubs. The black bear’s long, curled claws help them to climb tree trunks to reach seeds, nuts, and leaves; and allow them to rip open logs and insect mounds; and overturn rocks to scavenge for insects. These bear have plantigrade feet allowing them to stand uprightly quickly and improve their ability to hear and see. Also the bear can stand to tear apart huge tree trunks or fence posts, to display aggression against other bears. They also use their noses to detect mates, sniff and avoid danger and find food. When the black bears search for prey, they primarily rely on their sense of hearing and smelling to locate nuts, berries, and other plant foods. http://blackbearinfo.com/biology/
Experiment 1: Effects of pH on radish seed germination
Table 1: Radish Seed Observation and Germination (6 pts)
Solution pH Days 1-2 Day 3 Day 4
Observation Seeds Germinated % Observation Seeds Germinated % Observation Seeds Germinated %
Water 5 4 seeds burst from shell in full, the others are barely shooting up from their shells 10 100% All seeds shoot up 10
100% Full bloom of green leaves, but leaning to the sides 10
100%
Vinegar 4 Light shell color 0 0 No changes
0 0 No changes 0 0
Baking Soda 8 Dark brown color shell 0 0 No changes 0 0 No changes 0 0
Table 1 Continued: Radish Seed Observation and Germination (6 pts)
Solution pH Day 5 Day 6 Day 7
Observation Seeds Germinated % Observation Seeds Germinated % Observation Seeds Germinated %
Water 5 8 standing uprightly 10 100% All are standing uprightly 10 100% All are growing tall, Almost touching the petri dish lid 10 100%
Vinegar 4 Light shell color 0 0 No changes 0 0 No changes 0 0
Baking Soda 8 Dark brown shell 0 0 No changes 0 0 No changes 0 0
Experiment 1: Post-Lab Questions (15 pts)
Create your own graph and insert here as an Excel file or jpg file. Otherwise, you can draw on this figure and scan it into your computer for submission:
1. Dissect the IV and DV in this experiment. Why was it a true experiment?
The IV was the radish seed. The DV was the water, vinegar and Baking soda. The experiment shows that acidic precipitation can affect the health of a seed and impact the survival rate. When seeds were given basic water they were clearly able to thrive and grow on their own, however when seeds are given vinegar or baking soda mixed with water there was no hope for them to live.
2. Was there any noticeable effect on the germination rate of the radish seeds as a result of the pH? Compare and contrast the growth rate for the control with the alkaline and acidic solutions. Yes there was a noticeable effect on the germination rate of the radish seeds when acid and base were compared with water. When compared with water both solutions produced no growth. When given basic water the seeds were able to thrive and grow. When given vinegar or baking soda mixed with water they were no growth.
3. According to your results would you say that the radish has a broad pH tolerance? Why or why not? Use your data to support your answer.
No. Radish seeds do not have a tolerance for a range of pH values. The radish seeds only thrive with water. Water has a pH value of 5. Even though the vinegar had a pH difference of only 1, it grew no seeds. Likewise, the baking soda whose pH was 3 levels higher, also produced no growth.
4. Knowing that acid rain has a pH of 2-3 would you conclude that crop species with a narrow soil pH range are in trouble? Given that the PH level of water is 7 and the seeds were able to grow perfectly fine in a substance that is at PH 7, but did not grow in vinegar or baking soda, which is in the same range as acid rain, then the conclusion must be that crop species are in trouble. Improper PH will be a real problem to farmers and those growing crops. In my opinion, acid rain is a farmer’s worst nightmare because the growth of many crops will be affected.
5. Research and briefly describe a real world example about how acid rain affect plants. Be sure to demonstrate how pH contributes to the outcome, and proposed solutions (if any). Descriptions should be approximately 2 – 3 paragraphs. Include at least three scientific citations (use APA formatting).
There are many reports of the effects and damage that acid rain can have on our forest. It can cause slower plant growth, weaker trees by damaging their leaves and roots, it can restrict the nutrients that plants need to survive and it expose them to toxic substances that is slowly being released into the soil. According to the EPA “acid rain has been implicated in forest and soil degradation in many areas of the eastern U.S., particularly high elevation forests of the Appalachian Mountains from Maine to Georgia.” The two main cause of acid rain is sulfur dioxide and nitrogen oxide. Acid rain happens when oxides of nitrogen and sulfite combined with moisture in the atmosphere and create nitric and sulfuric acid. Any precipitation with a pH level lesser than 5.6 is considered to be acid rainfall which overtime will cause the soil to be so acidic that it will kills or stunts plant life. (A PH scale is used to determine if a specific solution is acidic or basic. Any number less than seven is considered acidic. The lower the PH the more acidic the solution.)
When acid rain falls the soil’s pH slowly develop an acidic level that dissipate vital minerals found in the soil. This decrease of essential minerals and the release of aluminum inhibit the trees from absorbing water. This can be seen when some tree leaves become yellow and the trees cease from producing nuts or fruits. Another harmful effect is when the outer waxy layer of the leaf is damage and can no longer protect the plant from drying out. This leads to the disruption of the chloroplasts that stimulate photosynthesis for the plant (National Geographic, 2014). The roots of the trees can also be affected and can cause the trees to stunt and even kill the roots. Hence tree reproduction can also be affected negatively.
Since the two main causes of acid rain is sulfur dioxide and nitrogen oxide, the decrease or elimination of these would be vital in the prevention of acid rain. Both chemicals are by products of fossil fuel. To lessen the use of fossil fuels people can car pools, use public transportation, or walk to reduce tons of nitrogen oxide emissions that is produced in our transportations system. The other chemical sulfur dioxide, is emitted by our huge factories and other industries. This can be reduce by adding scrubbers to utility plants. An alternative source for power can also be used in power plants to reduce emissions. Another proposed solution is to replace older appliances and older electronics with modern energy efficient products.