Using a Heart Model to Study for AP Biology – Explore On a Deeper Level

Students in AP Biology have more opportunities for in-depth and hands-on experiences in the classroom. Learn how using a heart model to study can be beneficial when taking AP Biology.

Using A Heart Model To Study For AP Biology

Since Biology is the study of living organisms, it’s essential to learn about and understand how the heart works. Although the basic functions of the heart are often taught at an early age and in elementary school, AP Biology provides the perfect opportunity to explore the unique organ at a deeper level.

While there are typically many lab sessions where students have the chance to examine and dissect a real heart, it’s not always the ideal model when studying the heart. We’ll discuss some of the ways that using a heart model can enhance and improve the overall learning experience in AP Biology.

Taking A Look At Heart Models

Walk into any AP Biology lab or even a doctor’s office, and there’s a good chance that you’ll see a model of a human heart on display. As an AP Biology student, exploring a human heart model may be the closest, you’ll get to human heart unless you decide to advance in the sciences or attend medical school.

Have a big exam coming up or just want to gain a better understanding of how all of the parts of the heart works? A model of a heart is an excellent resource for studying. If your AP Biology teacher has a heart model, you are probably encouraged to take a look at it in the classroom, but what can you use when you’re studying outside of the classroom?

what can you use when you’re studying outside of the classroom?

Quick Study Illustrations

Your Biology book may have some stunning and highly-detailed graphics of a human heart, but it may not showcase every part in detail. You can find a variety of “quick study” pamphlets online that give you multiple views of the human heart, and in great detail.

This type of resource is nice for studying while “on the go,” or when you want something lightweight and compact, but it is still very similar to looking at a model of the heart in your textbook. If you are a visual learner, this method may be enough to help you study, but if you’re a “hands-on” learner, you may have a harder time learning about the heart.

3D Model Apps

If you spend a lot of time at your computer or on your device while you study, it may be worthwhile to check out a 3D model of the heart. Depending on the 3D model you choose, you might be able to do virtual dissection, manipulate the heart rate, or see what happens to the heart during a heart attack.

While a 3D model that you can touch and manipulate with your own hands, may help you understand the heart better than an app, the app may be beneficial due to some of its features (such as a beating heart or blood flow).

3D “Hand On” Models

As we mentioned earlier, there might be a 3D model of the human heart in your AP Biology classroom, and you have access to it while you’re in class. 3D heart models typically have pieces that come apart and allow you to see all the parts of the heart, which is essential when learning about the complex organ.

When you want a more “hands-on” approach to studying the human heart, it can be difficult to have access to a 3D model, particularly if you’re in a large classroom with other students who are also wanting to see the model of the heart.

Purchasing a heart model for yourself might make studying more convenient and help information “sink in” a little better. If you’ve already started to search around online for 3D heart models, you might be a little disheartened by the price.

Many life-sized 3D heart models cost hundreds of dollars, and it might not be in your budget as an AP student. The good news is that there are many smaller 3D models available online for under $50.

If you decide to purchase a 3D model, it’s important to read the reviews before buying and keep in mind that the model will not be life-sized. Ideally, the 3D model should have parts that can be removed or at least moved out of the way, so that you can see all the parts of the heart.

Purchasing a 3D model of a heart can be a wise financial investment, particularly if you’re planning on pursuing Biology or other Life Sciences further. Your 3D model can also be a great asset to a study group or when using a variety of resources like the quick study pamphlet or 3D app.

Do You Have To Use A Heart Model When Studying?

You might be wondering if you need to use a model of a heart when studying for AP Biology. Your teacher may strongly recommend using heart models as a study guide, but as we mentioned earlier, you might understand how the heart works without looking at a model.

Even though we mention quick study pamphlets and 3D model apps as good alternatives to studying the heart, research suggests that students are more likely to understand and retain information better when they are presented with 3D models rather than 2D.

In one study, a group of nursing students was tested after learning and studying with 2D models, and the other group was tested (with the same test) after learning and studying with 3D models. Overall, the group that had access to a 3D model performed better on the test.

The methods, which were compared included a dissection of a sheep heart and a PowerPoint presentation versus a 3D heart model; the 3D model resulted in higher test scores.

Isn’t Dissection The Best Option For Studying The Heart?

Many may argue that dissecting a heart is the best way to study the heart and gain a better understanding of how it works. In AP Biology, you may have the opportunity to dissect a sheep heart or another mammal heart, but you won’t be able to have an up close and personal interaction with a human heart.

While dissection is a fascinating and “must have” experience in every Biology course, it can also be challenging to understand and often it’s a hurried process with limited explanations. It can also be more challenging when more than one student is working on dissecting a heart at once (such as a group of two or three people).

Dissection takes practice and time, and even though many students would benefit from one-on-one help from their instructor, it’s not always feasible. Dissecting a heart can also be very difficult for some students and may make them feel nervous or uneasy, which can also affect the overall learning experience.

Another reason why dissection may not be the best option for studying is that you can’t carry the heart around with you. Depending on how many students are in the class or how many class sessions touch and examine a heart, it can become harder to work with or easily damaged.

Ideally, every student would have the opportunity to dissect a heart and learn enough from the experience to understand how the heart works and ace an exam on how the heart functions. Since a heart is such a unique and complex organ, it’s beneficial to explore a variety of resources to help better understand the heart.

Dissection is a great option, but it’s not the only option (nor should it be) when providing an in-depth look at the heart. Unless you have a photographic memory, most students benefit from seeing the parts of a heart multiple times, not just during the various steps of a dissection.

Using a 3D model allows you to take the heart apart and put it back together as many times as you want. If the model is made of high-quality materials and is handled carefully, it can withstand many study sessions and years of science courses.

Using Various Heart Models For Studying

The type of heart models you choose will most likely depend on your learning style and preferences. Since learning about the heart is not something that is easily done overnight, it’s best to utilize as many resources as you can when you study.

If a model of the human heart is not available to you on a regular basis or at home, consider the 3D model app and even some of the quick study guides.

Biome Map: Definition, Examples, And Why It Is Important

If you want to gain a better understanding of all living things, from plants to animals, it’s essential to learn about biomes and the role they play in Biology. Learn how to read a biome map and define each type of biome in the world.

Biome Map: Definition, Examples, And Practice

Biomes are an interesting and important part of Biology, and without understanding what a biome is and how it works, you don’t have a full understanding of Biology. Let’s take an in-depth look at biomes, so you can take a look at a biome map and understand it; learning about biomes can also better prepare you for if you’re ever tested on a map of biomes.

What Is A Biome?

While you might have learned a little about biomes when you were in elementary school, there’s a good chance that you don’t have a biome map memorized or know about all of the biomes. As we all know, the entire surface of the planet has some lifeform, but it varies depending on factors like vegetation, climate, water, and light. A biome is classified by the flora and fauna (dominant plants and animal life) that resides in that particular area; the plants and animals that live in a biome are also known as biota. While some biomes share some characteristics, each type is unique, and the smaller units in a biome are what we know best as a habitat.Biomes are often mistakenly referred to as ecosystems (and vice versa). An ecosystem is made up of living organisms and the relationship that they have in their nonliving environment. There are many examples of ecosystems but think about a dark cave in a secluded part of the world and all of the known (and unknown) living things that live in the cave.One of the reasons why ecosystems may be easily confused with biomes is that a biome may have many different ecosystems.

Exploring The Different Types Of Biomes

If you look at a biome map, you will notice that it is color-coded with a key that refers to different types of biomes. Depending on what map you look at and who is teaching you about biomes, you may only learn about five biomes, which include tundra, grassland, forest, desert, and aquatic; sometimes it’s six basic biomes be splitting the aquatic into marine and freshwater.As you might guess, these biomes are basic, have a broad definition, and may refer to many parts of the globe. In order to gain a better understanding of Biology as a whole, you may want to consider learning more about other biomes like the rainforest, temperate forest, chaparral, taiga, savanna, temperate grasslands, and freshwater or marine.Younger learners or individuals who just want some basic information on biomes may benefit from learning about the broad classifications, but taking the time to learn about other biomes (and their specialized classifications) can help understand the world as a whole.As you explore biomes, it’s not uncommon to see different biomes in the same area, and often there are no clear boundaries from one biome to the next. If you were to compare a map of biomes from thousands of years ago to today, you’d see a completely different map.Climate change plays a significant role in how biomes are defined and where they are located on a map. The major biomes typically correspond to the climatic zones, such as a tropical wet climate.

Tundra

As you might already imagine, the tundra biome is located in the northernmost regions on a map of biomes. A tundra is flat, cold, but still has plant life during the short growing season. A variety of birds call the tundra their home during the summer and migrate in the winter. Smaller mammals thrive in their habitats under the snow.

Grassland

The grassland biome is often referred to as plains or prairie, due to the large areas of a variety of grasses. Grasslands typically receive minimal rain and are often at high risk for fires. Even though there is not a large variety of flora, the biome is home to large herding mammals. Grassland is found on every continent except for Antarctica.

Forests

The forest biome makes up about one-third of the Earth’s land area, and as you might imagine, there are more classifications to the forest biome than “just trees.” The tropical rainforest has two seasons, 12-hour days, and has little variation in the climate. You’re most likely to find tropical rainforest countries near the equator like South America, Southeast Asia, and Southern Africa.A temperate forest biome is most frequently found in eastern parts of North America, northeastern Asian, and western and central parts of Europe. Animals from small mammals (squirrels) to predators (black bears) call the biome their home. The boreal or taiga forest is similar to the temperate forest biome and is found in Siberia, Scandinavia, Alaska, and Canada. The taiga forest biome doesn’t have as long of growing seasons as the temperate forest, and the climate is cold and dry.

Deserts

It’s not uncommon to see all types of desert biomes lumped into one broad desert biome and again, depending on the map you’re looking at or who is teaching information about biomes, the classifications may be different. Some people break down the desert biome even further to include hot and dry, semiarid, coastal and cold. If you live in the U.S., you may be most familiar with a hot and dry desert biome, as it includes four of the major deserts in North America. The seasons are very dry and warm year round.Semiarid desert biomes may be found in parts of the U.S., but are also found in Newfoundland, Greenland, Europe, and parts of Asia. There are more flora and fauna in semiarid biomes than the hot and dry.The coastal desert biome sees moderate rainfall and the cold desert biome experiences heavy snowfall; both have plants and animals that have adapted to the environment (much like every other biome on the map)

Aquatic

When exploring a map of biomes, it’s important not to overlook the aquatic biome. While many people pay close attention to flora and fauna throughout the various biomes “on land,” there’s plenty to consider when we look at the bodies of water.The aquatic biome is typically divided into freshwater and saltwater (or marine) biomes. From there it might be broken down even more to ponds or lakes, rivers, oceans, and estuaries.It’s essential to think about aquatic biomes because just like other biomes, climate change and other environmental factors affect these “off land” biomes, which over time will change the layout of a map of biomes.

Why Are Biome Maps Important?

Image Source: askabiologist.asu.eduNow that you have a better understanding of the different biomes and how one map could be different from another, you might be wondering why biome maps are so important. As we mentioned earlier, learning about biomes and understanding where they are in the world can help us understand all living organisms. Biome maps can help people learn about places they may never get to see; the map may open their eyes to a new species of animal or a unique variety of flora. Biome maps may be a basic resource for understanding Biology, but without the maps, we know very little about Biology, it’s past, and what might be in store for the future of our planet.Even though we may not see drastic changes to our environment in our lifetime, we can see small scales changes such as more prairie fires or decreasing populations of a specific bird.To some, these may not seem like that big of a deal when comparing it to the world at large, but it can give us some idea as to how biome maps will continue to evolve.

Making The Most Of A Biome Map

Not only are biome maps an important resource to use in a Biology course, but it can be used in a variety of fields such as Agriculture. The United States Department of Agriculture can utilize the map to learn more about soil distribution while conservation programs can strive to protect biomes that need it the most.

If your goal is to learn how to draw a map of biomes or memorize it for a class, you might want to consider the following tips.

Familiarize yourself with Geography; you can’t make a map without knowing where places are located.
Use the knowledge you already have. Think about living organisms and where they live. Can you guess what type of biome (or biomes) are in this area?
Get to know a climatic map. Remember climatic zones may correspond with specific biomes.
Practice, practice, practice. Make several copies of a blank world map.
Use a color-code and key that’s easy to read. Choose colors that stand out from one another.

Biological Magnification: Definition, Examples, and Practice

Biological magnification is a rising concern amongst researchers who examine the ways that chemicals and pollutants may have long-term effects on ecosystems. In this article, we’ll dive deep into what it is and the impacts it’s already had on our environment.

Biology researchers and students are likely familiar with the field of ecotoxicology, or the study of how chemicals and toxins affect ecosystems and their organisms. In this field, the term biological magnification is frequently used to describe the amplified concentrations of these substances as you move up through the food chain.

Also fittingly called bioamplification or biomagnification, this process explains why harmful substances like have metals, or chemicals found in fertilizers or pesticides, present in even the largest, carnivorous predators.

In this article, we will discuss the process of biomagnification and how it works. We will define the terminology, and then give real-life examples and case studies documenting how chemicals travel through soil, water, and smaller organisms to eventually make their way to the top of the food chain in large concentrations.

What is Biological Magnification?

Put simply; the term biological magnification is used to describe the process by which substances used in farming or produced in industrial waste make their way into and up the food chain.

We see increased levels of these toxins and chemicals accumulating through the trophic levels of the food chain thanks to this phenomena.

Pesticides, fertilizers, and heavy metals from industrial waste are some of the most common culprits who contribute to the problem.

Typically, the materials are carried through water sources like rivers, lakes, and streams as a result of surface runoff where they are then ingested by aquatic animals like frogs or fish. These small organisms are then preyed upon by predators higher up in the food chain, like birds, larger fish, or animals, which is how these same substances make their way into their body.

Many of these toxins and chemicals are fat soluble and get stored in their internal organs or fat tissue. This results in an accumulation of the substance over time and in greater concentrations the higher up the food chain you go. This phenomenon is called food chain energetics.

Although biomagnification doesn’t always have a direct effect on living organisms, long-term exposure to harmful chemicals may result in unpleasant and irreversible side effects that could threaten a species.

Biological Magnification vs. Bioaccumulation

It’s important to note that there is a significant difference between biomagnification and bioaccumulation. Although some may use the words interchangeably, they actually describe different scenarios in an organism.

Biological magnification specifically refers to increasing concentration of materials in each higher link in the food chain. However, bioaccumulation examines the increased presence of a particular substance inside a single organism.

While the two processes may be interconnected, for the purpose of this article it’s important to differentiate the terminology to understand the real-life examples and practice.

Examples of Biological Magnification

There are numerous, well-documented examples of biomagnification where researchers find high concentrations of chemicals in apex predators. Many of these studies also demonstrate the potential negative consequences of this build up over time. Here are a few examples.

Bald Eagles

During World War II troops faced a plethora of health issues, including outbreaks of malaria, body lice, typhus and bubonic plague spreading through mosquito bites at encampments throughout the world.

DDT is a pesticide that was developed to kill these biting bugs to help control the spread of these diseases, and following the war had agricultural applications. Farmers used the product on their crops to control pests, and it was both popular and widespread thanks to its low cost and easy application.

It was approved as being safe and effective by the EPA at the time because there did not appear to be any harmful side effects of ingesting the chemical in animals or humans. However, this did not take into account the possibility of biomagnification.

DDT doesn’t break down over short periods of time in the environment and is a substance that gets stored in the fatty tissues of animals who consume it. This became particularly problematic for bald eagles.

A predator near the top of the food chain, bald eagles were consuming large quantities of fish who had been affected by the chemical. Runoffs from farms hit the waterways, and DDT infiltrated aquatic plants and animal life, and the eagles ingested the chemical with each meal they ate.

Over time, the chemical disrupted their ability to lay eggs with strong shells, causing the bald eagle population to decrease to the point of near extinction. In 1940, Congress stepped in to pass an act to protect the species, but DDT wasn’t banned until 1972.

It wasn’t just species of eagles affected. Other predator birds like brown pelicans and peregrine falcons saw the same side effects. The thinning off the eggshells made incubation and hatching near impossible and also threatened these bird populations.

Fish and Pregnancy

Another notable example of biomagnification is in predator fish. Species like Shark, Swordfish, Orange Roughy, Tuna, King Mackerel, or Tilefish contain proportionally larger levels of toxic mercury than smaller fish and shellfish.

In fact, the levels are so high that the FDA advises that pregnant women avoid consuming these species for fear of exposing developing fetuses to levels that may cause nerve damage.

How does this toxicity occur? Mercury is introduced into the ecosystem in one of two ways. As a naturally occurring element, it can leach from rocks and volcanoes into our water supply over time, but those natural changes are not likely to significantly impact the environment.

However, when you take the natural occurrences and combine them with human contributions through coal-burning power plants which impact the air, rain, soil, and water around these facilities, the mercury levels rise drastically.

As we now know, once an element enters the water supply, it’s inevitable that it gets ingested by aquatic life at every level of the food chain. When plankton and small crustaceans that make up the majority of the diet of the larger, predatory fish have moderate levels, then the species who eat them will have a compounded effect.

For example, according to the FDA, the average amount of mercury found in a serving of scallops is 0.003 parts per million. Lobsters, one of the main predators of the scallop have a concentration of 0.107 parts per million.

Monkfish love dining on lobster, and have an average of 0.161 parts per million of mercury in their system, and shark and swordfish at 0.979 and 0.995 parts per million respectively regularly dine on monkfish.

In this example, it’s easy to see how quickly the effects compound and how concentrated they become with only four steps up the food chain ladder.

What Causes Biological Magnification?

Although biomagnification is a natural phenomenon that happens in all organisms, the instances where it is worrisome are largely due to anthropogenic factors. Materials that humans introduce into the environment can cause unexpected and hazardous side effects and typically fall into one of the following subcategories.

Organic Contaminants

We live in an age where the word organic is closely correlated with natural and healthy, but too much of anything could be bad. Organic elements like phosphorus, nitrogen, and carbon are necessary for survival, but if they appear in excessive quantities in ecosystems, they may cause eutrophication.

Eutrophication is a phenomenon when an organism that thrives in these conditions, like algae, for example, experience exponential growth and suddenly have an overwhelming population. This can then disrupt the ecosystem and kill off other organisms because there aren’t enough resources, like oxygen, to go around.

Waste

Waste produced from manufacturing plants, factories, and other industrial enterprises can release waste and toxins into the air and water that contribute to the problem.

Agricultural and Industrial

Chemicals introduced into the environment from inorganic pesticides, fungicides, fertilizers and herbicides that mix with our natural water sources due to runoff when it rains release toxic elements as well.

Plastic Pollution

Not only does plastic physically impact our environment, often ending up in our oceans and disrupting marine ecosystems, but it can also leach toxic chemicals into water too.

For example, Bisphenol A, or BPA, has made headlines recently as a substance that can produce a range of health conditions in humans that is used in making plastic water bottles. It is one of the leading chemical pollutants in the environment.

Heavy Meals

As we discussed in our earlier case study, heavy metals that enter our water sources can wreak havoc on the ecosystem. Mining activities are sometimes at fault for releasing deposits that can pollute aquatic plants and contaminate water sources with elements like zinc or cobalt.

Potential Negative Effects of Biological Magnification

DDT and mercury aren’t the only hazardous substances that have the potential to biomagnify. Substances like polychlorinated biphenyls (PCB’s) that can impair reproductive systems, heavy metals, polynuclear aromatic hydrocarbons which are a known carcinogenic, cyanide, and selenium have been extensively studied and proven to have similar outcomes.

There are dozens of potential adverse effects to our environment, including but not limited to:

Reproductive implications for marine and other animal life
Killing coral reef ecosystems
Disrupting the natural food chain as species die off

There is also a significant risk of health impacts on humans who consume many of the organisms affected by this process. They include an increased risk of the following:

Cancer
Kidney failure
Liver disease
Birth defects
Brain damage
Respiratory disorders
Heart disease

Final Thoughts

Bioamplification isn’t a new phenomenon, but the humans have introduced pollutants to the environment that makes it a threat to the ecosystem and our food sources. Understanding how and why it occurs is the first step to combating the problem and preventing the destruction over time.

Conversations and advocacy for sustainability need to continue to ensure the long-term health of our environment.

Dimensional Analysis: Definition, Examples, And Practice

If you’ve heard the term “dimensional analysis,” you might find it a bit overwhelming. While there’s a lot to “unpack” when learning about dimensional analysis, it’s a lot easier than you might think. Learn more about the basics and a few examples of how to utilize the unique method of conversion.

Dimensional Analysis: Definition, Examples, and Practice

As a student of Biology or any of the sciences, you will have to use math of some kind, and there’s a good chance that you will find dimensional analysis (or unit analysis) to be helpful. Math equations and other conversions can be overwhelming for some, but dimensional analysis doesn’t have to be; once you learn it, it’s relatively easy to use and understand.

We’ll give you the basics and give you some easy-to-understand examples that you might find on a dimensional analysis worksheet so that you can have a general understanding about what it is and how to use the technique in all types of applications as you continue to take science courses.

What Is Dimensional Analysis?

As we mentioned, you may hear dimensional analysis referred to as unit analysis; it is often also known as factor-label method or the unit factor method. A formal definition of dimensional analysis refers to a method of analysis “in which physical quantities are expressed in terms of their fundamental dimensions that is often used.”

Most people might agree that this definition needs to be broken down a bit and simplified. It might be easier to understand this method of analysis if we look at it as a method of solving problems by looking converting one thing to another.

While dimensional analysis may seem like just another equation, one of the unique (and important) parts of the equation is that the unit of measurement always plays a role in the equation (not just the numbers).

We use conversions in everyday life (such as when following a recipe) and in math class or in a biology course. When we think about dimensional analysis, we’re looking at units of measurement, and this could be anything from miles per gallon or pieces of pie per person.

Many people may “freeze up” when they see a dimensional analysis worksheet or hear about it in class, but if you’re struggling with some of the concepts, just remember that it’s about units of measurements and conversion. Dimensional analysis is used in a variety of applications and is frequently used by chemists and other scientists.

The Conversion Factor in Dimensional Analysis

One important thing to consider when using dimensional analysis is the conversion factor. A conversion factor, which is always equal to 1, is a fraction or numerical ratio that can help you express the measurement from one unit to the next.

When using a conversion factor, the values must represent the same quantity. For example, one yard is the same as three feet or seven days is the same as one week. Let’s do a quick example of a conversion factor.

Imagine you have 20 ink pens and you multiply that by 1; you still have the same amount of pens. You might want to find out how many packages of pens that 20 pens equal and to figure this out, you need your conversion factor.

Now, imagine that you found the packaging for a set of ink pens and the label says that there are 10 pens to each package. Your conversion factor ends up being your conversion factor. The equation might look something like this:

20 ink pens x 1 package of pens/10 pens = 2 packages of ink pens. We’ve canceled out the pens (as a unit) and ended up with the package of pens.

While this is a basic scenario, and you probably wouldn’t need to use a conversion factor to figure out how many pens you have, it gives you an idea of what it does and how it works. As you can see, conversion factors work a lot like fractions (working with numerators and denominators)

Even though you’re more likely to work with more complex units of measurement while in chemistry, physics, or other science and math courses, you should have a better understanding of using the conversion factor in relation to the units of measurement.

Steps For Working Through A Problem Using Dimensional Analysis

Like many things, practice makes perfect and dimensional analysis is no exception. Before you tackle a dimensional analysis that your instructor hands to you, here are some tips to consider before you get started.

Read the problem carefully and take your time
Find out what unit should be your answer
Write down your problem in a way that you can understand
Consider a simple math equation and don’t forget the conversion factors
Remember, some of the units should cancel out, resulting in the unit you want
Double-check and retry if you have to
The answer you come up with should make sense to you

To help you understand the basic steps we are using an easy problem that you could probably figure out fairly quickly. The question is: How many seconds are in a day?

First, you need to read the question and determine the unit you want to end up with; in this case, you want to figure out “seconds in a day.” To turn this word problem into a math equation, you might decide to put seconds/day or sec/day.

The next step is to figure out what you already know. You know that there are 60 seconds to one minute and you also know that there are 24 hours in one day; all of these units work together, and you should be able to come up with your final unit of measurement. Again, it’s best to write down everything you know into an equation.

After you’ve done a little math, your starting factor might end up being 60 seconds/1 minute. Next, you will need to work your way into figuring out how many seconds per hour. This equation will be 60 seconds/1 minute x 60 minutes/1 hour. The minutes cancel themselves out, and you have seconds per hour.

Remember, you want to find out seconds per day so you’ll need to add another factor that will cancel out the hours. The equation should be 60 seconds/1 minute x 60 minutes/1 hour x 24 hours/1 day. All units but seconds per day should cancel out and if you’ve done your math correctly 86,400 seconds/1 day.

When doing a dimensional analysis problem, it’s more important to pay attention to the units and make sure you are canceling out the right ones to get the final product. Doing your math correctly important, but it’s easier to double-check than trying to backtrack and figure out how you ended up with the wrong unit.

Our example is relatively simple, and you probably had no problem getting the right answer or using the right units. As you work through your science courses, you will be faced with more difficult units to understand. While dimensional analysis will undoubtedly be more challenging, just keep your eye on the units, and you should be able to get through a problem just fine.

Why Use Dimensional Analysis?

As we’ve demonstrated, dimensional analysis can help you figure out problems that you may encounter in your everyday. While you’re likely to explore dimensional analysis a bit more as you take science courses, it can be particularly helpful for Biology students to learn more.

Some believe that dimensional analysis can help students in Biology have a “better feel for numbers” and help them transition more easily into courses like Organic Chemistry or even Physics (if you haven’t taken those courses yet).

Can you figure out a math equation or a word problem without dimensional analysis? Of course, and many people have their own ways of working through a problem. If you do it correctly, dimensional analysis can actually help you answer a problem more efficiently and accurately.

Ready To Test Your Dimensional Analysis Skills?

If you want to practice dimensional analysis, there are dozens of online dimensional analysis worksheets. While many of them are pretty basic or geared towards specific fields of study like Chemistry, we found a worksheet that has an interesting variety. Test out what we’ve talked about and check your answers when you’re done.

How many minutes are in 1 year?
Traveling at 65 miles/hour, how many minutes will it take to drive 125 miles to San Diego?
Convert 4.65 km to meters
Convert 9,474 mm to centimeters
Traveling at 65 miles/hour, how many feet can you travel in 22 minutes? (1 mile = 5280 feet)

Ready to check out your answers and see more questions? Click here.

Cell Parts: Structure and Function in Plant and Animal Cells

Cells and Transport Teaching Resources · High school biology; AP extensions where noted.

A cell is a working system: its structures cooperate to maintain conditions for life. Use this reference before asking students to label diagrams, build models, or explain transport. Materials: paper, a cell diagram selected by the teacher, and colored pencils if useful. No laboratory equipment is required.

Learning objectives

Connect a cell structure to a function rather than memorize a label alone.
Compare a typical plant cell, animal cell, and bacterial cell.
Explain how several structures cooperate to produce and export a protein.

Structures to know

Plasma membrane: the cell boundary that regulates exchange and carries proteins involved in transport and signaling. Plant cells have a plasma membrane inside the cell wall.
Cytosol and cytoplasm: cytosol is the fluid portion; in a eukaryotic cell, cytoplasm includes cytosol and structures outside the nucleus.
Nucleus: contains most of a eukaryotic cell’s DNA. The nucleolus helps assemble ribosomal subunits.
Ribosomes: assemble proteins using instructions carried by messenger RNA. They are not membrane-bound; bacteria have them too.
Rough endoplasmic reticulum: ribosomes associated with this membrane system make many proteins destined for secretion or membranes. The ER helps process those proteins.
Smooth endoplasmic reticulum: participates in lipid production; its other functions depend on cell type.
Golgi apparatus: modifies and sorts proteins and lipids for delivery.
Mitochondria: support aerobic cellular respiration and ATP production. Plant cells have mitochondria as well as animal cells.
Chloroplasts: carry out photosynthesis in photosynthetic plant cells. A root cell need not contain chloroplasts.
Vacuoles and lysosomes: plant central vacuoles support storage, breakdown, and water balance. Animal lysosomes carry out digestion and recycling. Vacuoles do more than store water.
Cell wall: a supporting layer outside the membrane. Plant walls contain cellulose; bacterial walls differ in composition.
Cytoskeleton: protein filaments contribute to cell shape, internal organization, movement, and division.

To decode cell vocabulary using word parts, start with cyto- for cell and endo- for within. Then check the full definition: a word’s parts do not explain the whole structure or process.

Compare cells with evidence

Typical plant and animal cells have a nucleus and membrane-bound organelles; bacteria lack a membrane-bound nucleus. All three have DNA, ribosomes, cytoplasm, and a plasma membrane. Size and outline alone cannot reliably identify a cell. Both plants and animals grow through cell division and cell enlargement.

Use this in a lesson

Ask students to label only structures supported by the selected diagram; a simplified picture may omit real structures.
For each label, require one function and one connection to another structure.
Trace a secreted protein from an ER-associated ribosome through the ER and Golgi to a vesicle that fuses with the plasma membrane.
Finish with an unfamiliar example: why would a cell that secretes many proteins need extensive rough ER?

Check understanding

Question: Is a cell without chloroplasts necessarily an animal cell? Explanation: No. Many plant cells, including many root cells, lack chloroplasts. Look for other evidence such as a cellulose wall. Question: Do plants respire only at night? Explanation: No. Plant cells carry out respiration during the day and night; photosynthesis depends on suitable light.

Teaching note: Distinguish observations from inferences. A classroom light microscope does not normally resolve ribosomes or the detailed membrane bilayer. For AP biology, ask students to connect internal membranes to compartmentalization.