Lab Notebook by Danielle Er

Set Up

de27203 — 2023-08-28 16:08:11 UTC

Question: Does more water increase the number of seeds that germinate?

Independent Variable: amount of water
Dependent Variable: number of germinated seeds
Constants: same container, same type of seeds, same temperature/humidity/sunlight (environment), same number of seeds in each container

Null Hypothesis: The amount of water has no effect on the number of seeds that germinate, and if there are any differences between the groups, that is simply due to chance.
Alternate Hypothesis: A greater amount of water will increase the number of seeds that germinate.

Brief Procedure: Place filter paper on the bottom of the Petri dishes. Pour water into the 5 Petri dishes. One has 0ml, one has 5ml, 10ml, 15ml, and 20ml. Then place 5 seeds in each dish. Put the lids on the containers, and leave them alone for 72 hours. After the 72 hours, check the seeds and record the number of seeds that germinated as well as the length of the seeds that germinated.

Length of Seed Graph

de27203 — 2023-08-29 15:57:33 UTC

Number of Seeds Graph

de27203 — 2023-08-29 16:08:09 UTC

Length of Seed Data Table

de27203 — 2023-08-29 16:08:43 UTC

Number of Seeds Graph

de27203 — 2023-08-29 16:09:27 UTC

CER

de27203 — 2023-08-29 16:20:23 UTC

Increasing the amount of water up to 10 ml increases the number of seeds germinated and the length of the seed sprouts; however, increasing the water above 10 ml does not affect the number of seeds germinated or the length of seeds, and any differences in germination and length between the amounts of water are due to chance. The graph shows that 0% of the seeds germinated when there was 0 ml of water, while approximately 75% of the seeds germinated with 5 ml of water, and with 10 ml of water, over 90% of the seeds germinated. However, with 15 ml and 20 ml of water, the percentage of germinated seeds stayed approximately 90%. From this data, one can conclude that more seeds will germinate with 10 ml of water versus with 0 or 5 ml of water because the seeds are fully submerged in water. However, the fact that the germination rate stayed about the same for 10, 15, and 20 ml of water, shows that increasing the water above 10 ml does not increase the number of seeds that germinate. This is probably because there is a maximum rate at which the seeds can intake the water, so adding more than 10 ml does not benefit the germination. Similarly, the average length of the seed sprouts with 0 ml of water was 0 cm, and the average length of the seed sprouts with 5 ml of water was 1.16 cm, while the average length with 10 ml of water was 2.13 cm. With 15 and 20 ml of water, the average lengths were 2.22 and 2.44, but because the error bars overlap for 10, 15, and 20 ml of water, they have to be considered the same. Because the increase in length is significant when there is 10 ml of water versus 0 or 5 ml one can conclude that increasing the water to 10 ml will cause the length to increase because that is their maximum intake. On the other hand, because there is not a significant difference in length when the water increases to 15 or 20 ml versus the length with 10 ml of water one can conclude that more than 10 ml of water does not increase the length because the seeds are not able to take in more than 10 ml of water.

Set Up

de27203 — 2023-09-01 15:41:22 UTC

Question: Are the isopods more likely to stay in a wet environment or a dry environment?

Independent Variable: wet or dry filter paper
Dependent Variable: number of bugs on each side (wet or dry)
Constants: number of bugs on each side, temperature, type of bugs, type of paper, same size spaces

Null Hypothesis: The wetness of the environment does not impact the number of bugs on either side and any differences between the groups are due to chance.
Alternate Hypothesis: There will be more bugs on the wet side and fewer bugs on the dry side.

Brief Procedure: Place wet filter paper on one side of the container and dry filter paper on the other side. Place 5 bugs on each side. Record how many bugs are on each side every 30 seconds for a total of 10 minutes.

de27203 — 2023-09-01 15:55:57 UTC

de27203 — 2023-09-01 15:56:16 UTC

CER

de27203 — 2023-09-01 16:14:02 UTC

The bugs are more likely to stay in the wet environment versus the dry environment. The evidence shows that there were an average of 7.6 bugs in the wet environment and 2.4 bugs in the dry environment during the experiment. The graph with error bars shows that these averages do not overlap, which means that there is a significant difference between the wet and dry data. It is more likely that the bugs will stay in the wet environment because they are related to crustaceans, which live in water. These bugs have adapted to living on land, but they still have gills, which have to remain wet in order for them to breathe. This is why these bugs often live in wet environments such as underneath logs.

Set Up

de27203 — 2023-09-18 16:14:28 UTC

Question: Do the existing nutrient levels of the water influence the growth rates of the Duckweed?

Independent Variable: amount of nutrients in the water
Dependent Variable: how much the Duckweed grows
Constants: same container, same water, same amount of water, same type of nutrients, same type of plant, same number of plants, same environment

Null Hypothesis: The amount of nutrients in the water does not impact the growth rates of the Duckweed, and any differences between the groups are due to chance.
Alternate Hypothesis: More nutrients will cause the Duckweed to have a higher growth rate.

Materials: container, water, miracle grow, and, Duckweed plants

Brief Procedure: Fill containers with water. Add a different amount of nutrients to each. Leave one container of water without nutrients. Place the same number of Duckweed plants in each container and let them grow for 10 days. After 10 days, record how much they grew.

Set Up

de27203 — 2023-10-02 15:58:29 UTC

Question: Is there greater insect biodiversity near a water source or farther away from a water source?

Independent Variable: location of insect trap
Dependent Variable: biodiversity of insects caught
Constants: same type of trap, number of traps in each location, same approximate height of trap, same general location, same amount of time

Null Hypothesis: The location of the traps has no effect on the biodiversity of the insects caught, and any differences between the groups are due to chance.
Alternate Hypothesis: There will be greater insect biodiversity near the water compared to the insect biodiversity on the hill.

Materials: sticky traps, string

Brief Procedure: Go out to Community Park and hang the traps with string on trees/other vegetation, six on the hill, and six near the pond. They were a minimum of 10 meters apart and about 1-2 meters from the ground. We let the traps stay out for 24 hours. Bring the traps inside and determine how many species of insects and the population of each species for the hill and near the water. Then calculate and compare the biodiversity using the Simpson Index for the insects on the hill and near the water.

de27203 — 2023-10-02 16:06:53 UTC

de27203 — 2023-10-02 16:07:05 UTC

CER

de27203 — 2023-10-02 16:15:59 UTC

High levels of nitrogen cause more duckweed plants to grow. The graph shows that with 30 drops of nitrogen, there is consistently a higher number of duckweed plants compared to the other groups which had less nitrogen. This is especially obvious after eight days where there were 47 duckweed plants in the container with 30 drops of nitrogen. The second largest population was 24 for the control group, which means that the group with 30 drops of nitrogen is approximately a 95% increase. At 10 days the 20 drop group was the second highest population at 37 duckweed plants, and the 30 drop group was the highest population at 64 duckweed plants. This shows approximately a 79% increase in the number of plants from 20 drops to 30 drops of nitrogen. This data shows that the plants require large amounts of nitrogen, a type of nutrients, to grow. Because nitrogen is an important nutrient for plants, having high amounts of that nutrient results in high amounts of growth. That is why the largest population of plants is the one that was provided the most nitrogen.

de27203 — 2023-10-03 15:55:16 UTC

CER

de27203 — 2023-10-03 16:01:58 UTC

The proximity to a water source does not impact the biodiversity of insects in Community Park. The Simpson Index for the insects near the water was 0.69 and the hill was 0.68. The difference between these values is only 0.01, which is not a significant difference at all. However, there were 33 insects caught by the water and only 19 on the hill. This evidence shows that the two locations do not have different levels of biodiversity, but there are a greater number of insects by the water, which means there is greater abundance. However, the hill had more different types of species, which means there is greater richness. This could be caused by the fact that both locations have their own characteristics that allow them to support a certain number of species, but one location doesn't have significantly more beneficial characteristics than the other that would allow one location to support more life. Also, the fact that there was a greater number of insects caught by the water could be explained by there being more resources, which allows that location to have a greater carrying capacity and support more insects.

Set Up

de27203 — 2023-10-20 15:59:19 UTC

Question: How does germination affect the respiration rate in mung beans?

Independent Variable: mung bean wetness/germination stage

Dependent Variable: amount of CO2/rate of respiration

Constants: same number of beads/beans, same containers, same timing, same sensors, same temperatures

Null Hypothesis: The germination of the beans will not affect the rate of respiration in mung beans, and any changes between the groups are due to chance.

Alternate Hypothesis: The wetter, germinating mung beans will have a higher rate of respiration.

Materials: glass beads, dormant mung beans, germinating mung beans, three plastic containers, CO2 sensors, Chromebook

Brief Procedure: Place 40 glass beads in a container. Also, place 40 dormant beads and 40 germinating beads in another two containers. Use the sensor to record the initial amount of CO2. After 10 minutes, record the amount of CO2 as well as the change in CO2 levels. Repeat the process for each container.

de27203 — 2023-10-23 15:44:05 UTC

de27203 — 2023-10-23 15:44:18 UTC

CER

de27203 — 2023-10-23 16:03:50 UTC

The germinating beans have a higher rate of respiration because germinating beans require more energy for growth.

The data shows that the average increase of CO2 for the germinating beans is 654.6, which is significantly above the increases of 8.4 and 19.7 which were found for the glass beads and dormant beans. This means that the germinating beans have a higher rate of respiration because, in the process of respiration, they emit CO2 into the air. A greater increase in CO2 means that the beans are respiring more. Germinating beans need to do more respiration than dormant beads because they need to grow. When they do cellular respiration they take in oxygen. The oxygen they take in is used to break down stored food the bean already has so that it can be used as energy. The bean then uses this energy to grow and develop.

Set Up

de27203 — 2023-10-30 15:46:58 UTC

Question: How does light intensity affect CO2 consumed in photosynthesis?

Independent Variable: Light Intensity

Dependent Variable: CO2 consumed

Constants: same container, number of leaves, type of leaves, lamp, sensor, timing

Null Hypothesis: Light intensity has no effect on the amount of CO2 consumed in photosynthesis, and any differences between the groups are due to chance.

Alternative Hypothesis: Higher light intensity will cause more CO2 to be consumed during photosynthesis.

Materials: containers, leaves, sensor, chromebook, lamps, cover for container that needs to be dark

Brief Procedure: Place 50 leaves in one container and 50 leaves in another container. Also, take two containers and do not put leaves in those containers. Place all of the containers in front of the lights, but cover one container with leaves and one container without leaves with aluminum foil. Use the CO2 sensors to measure the initial amount of CO2 in each container as well as the amount of CO2 at the end of 10 minutes. Then, calculate the change in CO2 for each container.

de27203 — 2023-10-30 15:48:39 UTC

de27203 — 2023-10-30 15:48:53 UTC

de27203 — 2023-10-30 15:49:05 UTC

CER

de27203 — 2023-10-30 15:51:31 UTC

Higher light intensity increases the amount of CO2 that is consumed because more intense light allows more photosynthesis to occur. The data from the lab shows that the leaves in the light consumed an average of approximately 93% of the CO2, while the covered container of leaves caused the CO2 to increase by approximately 150%. This data shows that more photosynthesis occurs when the leaves are in the light because, in photosynthesis, plants consume CO2, so the more CO2 consumed, the more photosynthesis that has occurred. The amount of photosynthesis that occurred for the leaves in the light canceled out the CO2 produced during cellular respiration. On the other hand, the leaves in the dark produced a large amount of CO2 because, without light, they could not go through photosynthesis, but since they were still going through cellular respiration and emitting CO2, the CO2 levels increased significantly. Light is necessary for photosynthesis to occur because it is "The energy from light causes a chemical reaction that breaks down the molecules of carbon dioxide and water and reorganizes them to make the sugar (glucose) and oxygen gas" (Smithsonian Science Education Center).

Set Up

de27203 — 2023-11-28 17:17:48 UTC

Question: How does the solute concentration affect the percent mass change?

Independent Variable: solute concentration

Dependent Variable: percent mass change

Constants: same potato, same size pieces, same amount of solution in each cup, same size/type cups, same amount of time

Null Hypothesis: Soute concentration has no effect on the percent mass change, and any differences between the groups are due to chance.

Alternate Hypothesis: Solute concentration will affect the percent mass change.

Materials: Potato, potato cutting materials, cups, different solutions, beaker, scale

Brief Procedure: Cut 15 potato pieces and divide them into groups of 3. Record the weight of each group. Take 5 cups and fill them, each cup being filled with a different solution. Place a group of 3 potatoes in each cup. Wait 24 hours, and then record the new mass of the potatoes. Finally, calculate the percent change from initial to final mass.

de27203 — 2023-11-29 16:37:26 UTC

de27203 — 2023-11-29 16:37:42 UTC

CER

de27203 — 2023-11-29 16:44:23 UTC

The solute concentration affects the percent change in mass because of osmosis. The evidence shows that when the solute concentration is 0, the mass increases by 21.1%; while, when the concentration is 0.8, the mass decreases by 28.9%. This can be explained by osmosis. The solution with a concentration of 0 was a hypotonic solution, while the potato was a hypertonic solution. Since the potato had more solutes than the solution it was submerged in, the water went into the potato to balance the concentrations. This increase in water caused the mass of these potato pieces to increase. On the other hand, the solution with a concentration of 0.8 was a hypertonic solution, while the potato was a hypotonic solution because it had less solutes than the solution it was submerged in. Water from the hypotonic potatoes left to go into the hypertonic solution in order to balance those concentrations. Whenever the solution has more solutes than the potato, the mass of the potatoes will decrease, and whenever the solution has less solutes than the potato, the mass of the potatoes will increase. This models what is seen in individual cells.