30 IB Biology IA Topic Ideas To Use

IB Pros Blog
February 23, 2024
30 IB Biology IA Topic Ideas To Use

An important part of the International Baccalaureate (IB) Biology program is the Internal Assessment (IA). It encourages students to think critically, do original research, and use what they've learned in practical contexts. Yet, deciding on a subject for the IA might be challenging. This article provides a list of 30 potential topics for an IA in IB Biology.

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30 Captivating Biology IA Topic Ideas for IB Students

1- look at how temperature affects enzyme function.

This proposed IA topic is about looking into how changes in temperature affect how enzymes work. Proteins called enzymes speed up chemical processes in living things. The optimum temperatures for the activity of various enzymes vary. Students may learn more about the connection between temperature and enzyme activity by doing experiments in which they try out various temperatures and record the results.

2- Investigating how various light wavelengths affect plant development.

For photosynthesis to take place, which is crucial for plant growth and survival, plants need light. Yet, the impacts of various light wavelengths on plant development are distinct. Students can learn more about the relationship between the wavelength of light and how plants grow by doing experiments with different wavelengths of light and watching how the plants grow.

3- Analyzing how various medicines affect bacterial growth

To combat bacterial infections, antibiotics are often prescribed. Antibiotics are drugs that inhibit the development of germs, yet they all work somewhat differently. Seeing how different drugs affect the growth of bacteria can help scientists figure out how well antibiotics work against different types of bacteria.

4 - Examining the impact of various salt concentrations on osmosis in potato cell cultures

Water molecules undergo osmosis as they go from a high-concentration region to a low-concentration region separated by a semipermeable membrane. By changing the concentration of solutes on either side of the membrane, salt may impact the rate of osmosis in potato cells. Students can test the relationship between the amount of salt in potato cells and the rate of osmosis by adding different amounts of salt and watching the rate of osmosis.

5- Investigating the Role of pH in the Photosynthesis of Aquatic Plants

The rate of photosynthesis in aquatic plants may be altered by changing the pH of the water. Students may learn more about how changes in pH affect the photosynthetic rate of aquatic plants by doing their experiments.

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6- looking at how varying sugar levels affect yeast fermentation

Yeast cells transform sugar into alcohol and carbon dioxide via a process called yeast fermentation. The concentration of sugar may influence the pace of fermentation. Students may test the correlation between sugar content and yeast fermentation by brewing a batch with varying quantities of sugar and monitoring the pace of fermentation.

7: Researching how physical activity affects blood pressure and the heart rate

By boosting the body's need for oxygen and nutrients, exercise has the potential to raise heart rate and blood pressure. Exercise has been linked to improved cardiovascular health, which students can study by measuring their heart rate and blood pressure before and after a workout.

8- Examining Caffeine's Impact on Reaction Times

As a stimulant, caffeine may influence cognitive processes such as response speed. Students may learn more about how caffeine affects response time by taking a test before and after they consume caffeine.

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9. Researching the impact of CO2 levels on insect respiration rates

Insects can't breathe in high amounts of carbon dioxide because it prevents them from exchanging oxygen and carbon dioxide. Students can learn more about the link between CO2 levels and how fast insects breathe by doing experiments with different levels of CO2 and watching how the insect breathing rates change.

10 - Investigating the impact of various fertilizers on plant development

Fertilizers are helpful because they give plants the nutrients they need to grow well. However, different fertilizers have different effects on how plants grow. Students can find out how well different fertilizers work by doing experiments with them and watching how plants grow.

11- Studying how changing temperatures affect bacterial development

To thrive, bacteria need to be kept within certain temperature ranges. Students may learn about the correlation between temperature and bacterial growth by doing their experiments at varying temperatures and recording the results.

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12 - Analyzing the impact of various antacids on gastric acid

Those who have acid reflux or heartburn often use antacids, which are drugs intended to neutralize stomach acid. The effects of various antacids on stomach acid might vary. Students may learn more about which antacids are best for treating acid reflux by seeing how each one affects stomach acid.

13- Researching the Role of Noise on Plant Development

Sound waves may affect plant development by influencing hormone secretion. Students can look into the link between sound and plant growth by playing different sounds for plants and then watching how they grow.

14- Studying the Impact of Hydrogen Peroxide Concentrations on Catalase Activity

Hydrogen peroxide may be decomposed into harmless water and oxygen with the help of an enzyme called catalase. Hydrogen peroxide concentration may modulate catalase activity rate. Students may learn more about the correlation between hydrogen peroxide levels and catalase activity by doing their experiments.

15—Investigating how changing the pH of saliva affects the amylase enzyme's activity.

The salivary enzyme amylase breaks down carbohydrates into simple sugars. Saliva's pH may affect how active amylase is. Students may learn about the correlation between pH and amylase activity by testing the effects of varying the pH of their experiments.

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16- Studying how ethanol concentration affects the permeability of beetroot cell membranes (Experiment 16)

Alcohol's propensity to disrupt lipid bilayers may change cell membrane permeability. Students can see if there is a link between ethanol concentration and membrane permeability by watching what happens when ethanol is added to beetroot cells and how the color comes out.

17- Study of the Impact of Light Wavelength on Photosynthesis in Spinach Leaves

The presence or absence of specific light wavelengths may change the rate of photosynthesis. Students can see what happens to spinach leaves when they are exposed to different amounts of light to test how light wavelength affects photosynthesis.

18- Examining how various salt concentrations affect seed germination

By changing the soil's water potential, salt may prevent seeds from germinating. Students can find out how salt concentration affects seed germination by putting seeds in different salt concentrations and watching how fast the seeds grow.

19- Investigating how various water sources affect plant development.

The dissolved minerals and nutrients present in the water may have an impact on plant development. Students may discover which kinds of water are best for fostering plant development by watering plants with each type and then monitoring plant growth.

20- Studying how different light intensities affect the photosynthesis of elodea plants

Given that light is the primary source of energy for the process, the amount of light available may have an impact on the speed of photosynthesis. Students can learn about how the amount of light affects photosynthesis by putting elodea plants in different amounts of light and watching how fast they grow.

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21- The influence of various sugars on yeast fermentation

Various sugars may have varying effects on yeast fermentation. By trying out different sugars and keeping an eye on how fast the yeast ferments, students can find out which sugars work best.

22- Investigating how various salt concentrations influence plant development

Since it changes the soil's water potential, salt may affect plant development. Students may learn about the connection between salt concentration and plant development by doing experiments in which they use varying quantities of salt and then record the results in terms of how much their plants have grown.

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23- Studying how different temperatures affect plants' ability to exhale

The evaporation of water from a plant's leaves is called transpiration. The temperature may affect the rate of transpiration. Students may learn more about the connection between temperature and transpiration by doing experiments in which they are exposed to varying temperatures and record their results.

24. Analyzing how various fertilizers influence plant development

Variations in nutrient content between fertilizer kinds may stunt or promote plant development. Students can learn about how different fertilizers affect the growth of plants by trying them out and comparing the results.

25- A Study of Physical Activity and Blood Pressure

The demand for oxygen and nutrients is increased during exercise, which might affect heart rate. Students may learn more about how exercise affects the heart rate by keeping a heart rate log before and after physical activity.

26- Researching the antibacterial effects of various medications

Antibiotics may inhibit bacterial development in a variety of ways. Students can find out how well different antibiotics work by giving bacteria to them and then watching how the bacteria grow.


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27- Examining Caffeine's Impact on Daphnia's Heart Rate

Daphnia is used a lot in laboratories because it is so small and easy to handle. Caffeine may have an impact on Daphnia's heart rate. Daphnia's heart rate may be monitored before and after being exposed to coffee, so students can learn more about the connection between the two.

28- Analyzing the impact of several water types on yeast respiration

The way yeast breathes may be affected by the minerals and nutrients that are dissolved in the water. Students can determine which kinds of water are best for boosting yeast respiration by doing experiments with various types of water and monitoring the rate of respiration in the yeast.

29- Pea plant development as a function of light intensity (Experiment No. 29)

The amount of light a plant receives is important because it determines how much energy it has for photosynthesis. Students may learn about the correlation between light levels and plant development by doing controlled experiments in the classroom.

30- Investigating how various soils affect plant development

Changes in the amounts of nutrients and minerals in different types of soil can affect how plants grow. Students may learn which soils are best for plant development by planting the same kind of plant in each soil type and then comparing the results.

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These suggestions for the IA study are meant as jumping-off points, not as final destinations. Create your research topic and hypothesis with the help of these examples. Keep in mind that IAs that are targeted, well-structured, and make use of relevant scientific approaches and procedures tend to fare the best. I hope your studies go well.

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