Chapter 1: Biology - Exploring Life

Hi general biology students and welcome to chapter one which is about biology exploring life. I usually try to keep the lectures to 30 to 45 minutes just so that I don't lose a lot of you and so I would encourage you to work through the powerpoint on your own, read the textbook, listen to the lecture powerpoint, and then ask me any questions that you might have about the chapter. So here's kind of an introduction to biology. We're going to first start talking about red pandas, which are well adapted for life in the mountainous forests of Asia. They have red and white coats that act as a camouflage, and their long bushy tails help them balance in the trees and provides warmth during the winter. They have a bony projection in their wrists that helps them grasp one of their favorite foods, bamboo. And we talk about how if red and giant pandas are closely related, scientists once thought so but have since reclassified red pandas into their own family. This is a look at what a panda looks like and scientists are trying to figure out who are their closest relatives, but they've kind of adapted to where they're living to take advantage of the environment where they live. So this is taking a look at chapter one, big ideas. We'll talk about biology, the scientific study of life, the process of science. And then the five unifying themes in biology. And we'll talk a little bit about that structure shortly, which is a DNA double helical. So biology, the scientific study of life. I love biology because it's about the science of life. But what is life? Properties of life include order. So something must have order to be alive. It must be able to reproduce, grow, develop, be able to process energy, be able to regulate. itself, so kind of maintain a balance in the environment. It has to be able to respond to changes in the environment and kind of adapt through an evolutionary process that adapts itself to the environment where it's living. The cell is the simplest structural and functional unit of life. And here's a look at some of the properties of life that we'll go through. Things must have order. be able to reproduce, grow and develop, respond to the environment, process energy, so eat something and then be able to create energy from that food to be able to perform all of that organism's process. Adaptation like the panda we talked about, based on where it lives, it has adapted certain characteristics to take advantage of its environment and the ability to regulate. So this is showing a lizard kind of maintaining its inner temperature by sunning in on a rock. So these are just pictures that take you through kind of these major properties of life that I'll skip over for now. Checkpoint question, how is life recognized? And life can be characterized by the properties in the figures that we just talked about. Biologists will arrange the diversity of life into three domains, and taxonomists will name the species and classify them into even broader groups. There's a consensus among biologists that life can be organized into three higher levels called domains. These domains are bacteria and archaea, which contain organisms with simple cells, and the domain eukarya includes various protists and the kingdom's fungi, plantae, and animals. where we fall. So here's a look at and then the eukarya domain and then what exists in each. So here's a look at the bacteria domain, the domain which I studied a lot in an internship at one time, Archaea through the hot tide pools in Yellowstone National Park. Protists, which can be involved in multiple kingdoms. The kingdom Plante, which includes all the plants. Fungi Kingdom, which includes all mushrooms. Animalia, which includes all the animals. Which of the three domains of life do we belong? And that would be the Eukarya domain, which includes all the Animalia Kingdom. Biologists study life across a very broad range of scales from the molecules in a cell to the entire living planet and they divide this vast scope of biology into a series of structural levels and emergent properties result from the specific arrangement and interactions among the component parts. So here's a picture of life's hierarchy of organization. New properties will emerge at each level. So we kind of have the All these are labeled here, which are kind of hard to see in this picture. So I kind of want to go through one at a time. So we'll talk. So here is an organism. And an organism is kind of made up of organs and organ systems. And organs and organ systems are made up of tissues. Tissues are made up of cells, which can be made up of organelles. And organelles are made up of molecules, which are made up of atoms. And I want to take us back through, because I think this first picture, I can, let's see if it makes it a little bigger, kind of explaining everything about this life's hierarchy. So if we start with the biosphere, which includes the entire Earth, and we focus in Florida, we can look at a specific ecosystem, which is a section of Earth's biosphere. at a community, which can contain different populations of species. And if we look at one organism of species, then we get into what makes up an organism, the organs and organ systems, tissues, cells, the organelles, which are the small tiny organs within cells like the nucleus, and then molecules are made up of atoms, which make up all the organelles. And we'll go through that more as we get into the... chemistry side of things as well. So that's life's hierarchy, which you have a really should have a very good understanding of which of these levels of biological organization include all of the others in the list, cell, molecule, organ, and tissue. And the organ is the answer to that. So organ includes an organ includes tissues, molecules, and cells. And the process of science Science is a way of knowing. It's an approach to understanding the natural world. We talked a lot about this in our first lab for the week. Science uses an evidence-based process of inquiry to investigate the natural world. The scientific approach involves observations, hypotheses, predictions, tests of those hypotheses via experiments or additional observations and analysis of the data. And the scientific theory is broad in scope and support. by a large body of evidence. So here's a look, kind of an everyday observation. You probably use the scientific method without even realizing it. The flashlight doesn't work. That's an observation. So the question is, why doesn't the flashlight work? And you could have two hypotheses, which are again, answers to that question. Hypothesis one, the batteries are dead. Hypothesis two, the bulb is burned out. And then you might go through a series of experiments that have been done to make sure will help you answer that hypothesis. The prediction might be replacing the batteries. It will fix the problem if the batteries are dead. Or your prediction might be replacing the bulb will fix the problem if the bulb is burned out. So then you'll test both predictions by replacing batteries or replacing the light bulb. And the results will be the flashlight still doesn't work. So the hypothesis is contradicted. So meaning even when you put in new batteries, the flashlight still isn't working. Let's see what happens when you replace the light bulb. The flashlight does work. So the hypothesis is supported. Your hypothesis that said the bulb is burned out was the one that was supported. What's their main requirement for a scientific hypothesis? And again, a hypothesis is just an answer to a question that's formulated because of a problem or observation. And the main requirement for a scientific hypothesis is that it must be able to be tested. by experiments or by gathering further observations. In some sort of experiment of a hypothesis, researchers will often manipulate one component in a system and observe the effects of that change. The factor that will be manipulated will be the independent variable. The measure used to judge the outcome of the experiment is called the dependent variable, and this variable will depend on the manipulated variable. and the control experiment will compare an experimental group with the control group. The use of the control and experimental groups can demonstrate the effects of a single variable. For an example, researchers have found that mice models that did not match their habitat had higher predation rates than camouflaged models, and hypotheses can be tested in humans with clinical trials as well as retrospective or prospective observational studies. And this just shows a beach mouse and an inland mouse with their native habitat looking at how mice look different based on where they live because their camouflage will help keep them safe against predators. The beach population in its native habitat much lighter color to camouflage with the sand versus the inland population mouse again camouflage to help keep it safe from predators. The results from the camouflage experiment, the number of attacks on camouflaged models, and the number of attacks on non-camouflage models, so what this just means is a mice that was not able to camouflage or was taken out of its native habitat had much higher attacks because predators would just be more easily able to spot it. So that's just an example of the scientific method. Another checkpoint question, in some studies researchers try to match factors such as sex, gender, age, and general health for subjects in the control and experimental groups. What is this experimental design trying to do? And it's trying to ensure that the two groups will differ only in the one variable the experimental is designed to test. Scientists test hypothesis about the evolutionary relationships of red pandas that we talked a little bit about at the beginning. It's based on observations of physical similarities. Scientists initially hypothesized that the red panda was most closely related to a raccoon, but other scientists who observed their diet and habitat of red pandas said that they're similar to those of giant pandas. So it placed the two pandas together in their own family, but now recent studies compare the DNA sequences of both led scientists to classify red pandas as the only living species of their own family. So that's what's fun about science. It's constantly changing based on new information and it's always based on facts. It's not based on anyone on opinions. So again, there were two hypotheses for the group in which red pandas should be classified. One was based on what it physically looks like. So one A group of scientists said we should put it in the group with the raccoons because it looks more like a raccoon based on its physical appearance. The other group of scientists said, no, based on its diet, it should be paired with the giant pandas. And again, based on their DNA sequences, they've decided that it's its own separate family altogether. Forming and testing hypotheses are at the core of science, and this endeavor is influenced. by exploration and discovery, analysis and feedback from the scientific community. So scientists keep each other in check and make sure they're following the steps correctly of the scientific process and also societal benefits and outcomes. So how it can help in help animals and humans. So these are kind of more realistic model of the process of science, how kind of all three spheres are working together using hypotheses to form and test theories, but looking at how they benefit society, how other explorations and discoveries will affect these hypotheses and other feedback from the scientific community. Why is hypothesis testing at the center of the process of science? And it's central because it's a core component of science is testable explanations of nature. So remember the main thing that a hypothesis must be is it must be able to be tested. And that makes sense. If you're going to say something, or if you're going to say a prediction to a problem, you have to be able to test your prediction to be able to see if it's true or not. The goal of science is to understand natural phenomena. In contrast, the goal of technology is to apply scientific knowledge for some specific purpose. These two fields, however, are independent. Technological advances stem from scientific research and research will benefit from new technologies. Then we'll get into the five unified themes in biology. Life is distinguished by its unity and its diversity. The scientific explanation or theory for this unity and diversity is evolution, the process of change. That's transformed life on Earth from a... earliest forms to the vast array of organisms living today. And we can see the unity and diversity among birds, all the different types of birds, which is kind of cool. The American flamingo is my three-year-old's favorite, the hummingbird, and then the penguin. Evolution is the core theme of biology. The theory by Charles Darwin synthesized this theory by natural selection. So he looked at observations and then took inferences from those observations. Looking at heritable variations and overproduction of offspring led to natural selection, which is an unequal reproductive success leading to evolution of adaptions in certain populations. So here's a population with varied inherited traits. When we eliminate individuals with certain traits and reproduction of survivors, we get an increased frequency of traits that enhance their survival and reproductive success. So survival of the fittest is key here. Each species on earth today has a family history. A species represents kind of one twig on a branching tree of life that extends back in time, which is more and more remote. So we kind of see here an evolutionary tree theory of the red panda based on recent molecular data. So it's DNA structure to kind of see where the red panda fits in the family of other animals. Explain the cause and effect of unequal reproductive success. The answer here, those individuals with heritable traits are best suited to the local environment, will produce the greatest number of offspring. And over many generations, they're prepared to be a part of the family. portions of these adaptive traits increases in the population. Here's a great video on the blue-footed booby bird courtship ritual, which is really interesting. They have a way of attracting their mates by doing this cool dance. So if you download the PowerPoint, you'll be able to watch this video on your own too. And that owl batras courtship ritual as well. Evolutionary theory is useful in medicine, conservation, and agriculture. Through the selective breeding of plants and animals, humans also act kind of as agents of evolution by picking out the best and then breeding them together. As a result of artificial selection, our crops, livestock, and pets bear little resemblance to actually their wild ancestors. Explain how humans are agents of both artificial selection and natural selection. We use artificial selection when choosing specific traits or genes in organisms that we breed, like plants. or animals that was ultimately done to try to provide or increase our food source, especially for developing countries. And our intentional and unintentional manipulations change the environment and thus will affect natural selection. The process of life depends on the transmission and use of information. DNA is what we call the hereditary kind of programming blueprint. that programs and dictates all activities of the cells for proteins. Information from the external and internal environment includes stimuli, signals, and pathways that regulate body processes and gene expressions. These are the four building blocks of DNA, um, adenine, thymine, cytosine, and guanine. They're nitrogenous bases and they kind of fit together like a puzzle to kind of wind up this DNA in the helical. double-winded strand. So that's DNA, contains the genetic blueprint building blocks for the proteins in your cells. And the proteins in your cells go on to do all of your cellular processes, which means all of your life processes. So here's a gene X from a DNA strand and gene Y. RNA is transcribed from gene X. So information is kind of put into an RNA strand. which is then taken to create proteins in a cell. Gene Y is used to make an RNA transcription or a copy of that gene. The information flows to a component of a cell called a ribosome to create protein Y. So we get these different proteins X and Y from different strands on their DNA through a flow of information. An example of the flow of information. the regulation of the level of glucose in the blood is also important. So a signal in your blood might signal that there's high blood sugar levels or high glucose levels. In response to that, your pancreas will release insulin and insulin will bind to cells and it'll tell them to pick up extra glucose from your bloodstream to try to get your blood glucose levels back to normal. When that blood glucose levels get back to normal, the insulin levels will drop. Checkpoint question, how is signaling information involved in the expression of genetic information? Information from your internal and external environment will affect gene expression, where and when particular genes will be activated, and which proteins will be made. Structure and function are related. The relationship between structure and function can be observed at any level of life. At the molecular level, for example, a protein structure will correlate to its function. So, for example, hemoglobin molecules, it's a protein that has kind of four pieces to it, and it transports oxygen in the blood. On the cellular level, the long extension of your nerve cells will enable them to transmit impulses. incredibly quickly from your spinal cord to your toes. This is a look at the structural adaptations in the form of plant cell walls and insect exoskeletons that function in physical support of an insect. This is a CT scan showing the false thumb of a red panda and that's just shown here kind of the thumb doesn't exist or it's a lot smaller so it's able to pick up its bamboo a lot more easily. a red panda grasping the bamboo, and the scan showing the false thumb of a red panda. So structure and function are really important. Here's a video about a soaring hawk showing the structure of its wings, showing how it can soar through the air and kind of glide and float. Again a great video to watch, download the PowerPoint and you'll be able to watch all those. Look at the structure of your hand and explain how its structure supports its function. You'll notice that you have different joints in your fingers and in opposable digits, which allow you to manipulate objects. Opposable digits means your thumb is able to touch your fingers to pick up structures. Life depends on the transfer and transformation of energy and matter. Energy will flow through an ecosystem in one direction. It will enter as sunlight, be converted to chemical energy by a producer, such as a plant. Then it's passed on to a consumer, some sort of animal or insect that eats the plant, and then it will exit as heat. Ecosystems are characterized by the cycling of matter from the atmosphere and the soil through producers, consumers, and decomposers, which digest waste material, and then back to the environment. So this just takes you through the flow of energy in an ecosystem. The sun is the ultimate source of light energy. Plants use energy from the sun. to produce food. Leaves take up carbon dioxide from air, roots absorb water and minerals from the soil. Chemical energy from the food will be taken up by a consumer, an animal, which uses that energy to create, in food, to create its own energy to provide all its processes that it needs to go through. And then the outflow, the flow of energy exits as heat. And decomposers such as worms, fungi, and bacteria will return any sort of chemical back to the soil. And this is another kind of simple look at the flow of energy, inflow of light energy from the sun going into producers, going into chemical energy, into food, taken up by consumers, and then outflow of heat. And here's the moose as kind of that center part of the animal. Describe how photosynthesis transforms energy and matter. Photosynthesis uses the energy of sunlight, carbon dioxide, and water to convert into sugar molecules that makes plants, which store chemical energy, which consumers can then eat. The study of life extends from the microscopic scale of molecules and cells that make up an organism to the global scale of a living planet, and emergent properties are the result of interactions between the components of a system. Using an approach that we call systems biology, scientists can attempt to model the behavior of biological systems by analyzing the interactions among their parts. So for example, a box of bicycle parts won't do anything, but if the parts are properly assembled, you could take a ride. And what does this illustrate? It illustrates the emergent properties of the interacting components of a biological system. So here's a look at the interactions. among some of the components of an ecosystem, taking a look at that animal. You should now be able to kind of use this kind of these checkpoints at the end of the chapter to test your knowledge based on the chapter. And if you aren't able to do these, you can go back and read the textbook or ask me questions. And here are some of the figures that you can use to kind of double check how you're doing. Thanks for listening, guys, and we'll see you for the next chapter.

We're going to first start talking about red pandas, which are well adapted for life in the mountainous forests of Asia. They have red and white coats that act as a camouflage, and their long bushy tails help them balance in the trees and provides warmth during the winter. They have a bony projection in their wrists that helps them grasp one of their favorite foods, bamboo.

And we talk about how if red and giant pandas are closely related, scientists once thought so but have since reclassified red pandas into their own family. This is a look at what a panda looks like and scientists are trying to figure out who are their closest relatives, but they've kind of adapted to where they're living to take advantage of the environment where they live. So this is taking a look at chapter one, big ideas.

We'll talk about biology, the scientific study of life, the process of science. And then the five unifying themes in biology. And we'll talk a little bit about that structure shortly, which is a DNA double helical. So biology, the scientific study of life. I love biology because it's about the science of life.

But what is life? Properties of life include order. So something must have order to be alive. It must be able to reproduce, grow, develop, be able to process energy, be able to regulate. itself, so kind of maintain a balance in the environment.

It has to be able to respond to changes in the environment and kind of adapt through an evolutionary process that adapts itself to the environment where it's living. The cell is the simplest structural and functional unit of life. And here's a look at some of the properties of life that we'll go through. Things must have order.

be able to reproduce, grow and develop, respond to the environment, process energy, so eat something and then be able to create energy from that food to be able to perform all of that organism's process. Adaptation like the panda we talked about, based on where it lives, it has adapted certain characteristics to take advantage of its environment and the ability to regulate. So this is showing a lizard kind of maintaining its inner temperature by sunning in on a rock. So these are just pictures that take you through kind of these major properties of life that I'll skip over for now. Checkpoint question, how is life recognized?

And life can be characterized by the properties in the figures that we just talked about. Biologists will arrange the diversity of life into three domains, and taxonomists will name the species and classify them into even broader groups. There's a consensus among biologists that life can be organized into three higher levels called domains.

These domains are bacteria and archaea, which contain organisms with simple cells, and the domain eukarya includes various protists and the kingdom's fungi, plantae, and animals. where we fall. So here's a look at and then the eukarya domain and then what exists in each. So here's a look at the bacteria domain, the domain which I studied a lot in an internship at one time, Archaea through the hot tide pools in Yellowstone National Park. Protists, which can be involved in multiple kingdoms.

The kingdom Plante, which includes all the plants. Fungi Kingdom, which includes all mushrooms. Animalia, which includes all the animals.

Which of the three domains of life do we belong? And that would be the Eukarya domain, which includes all the Animalia Kingdom. Biologists study life across a very broad range of scales from the molecules in a cell to the entire living planet and they divide this vast scope of biology into a series of structural levels and emergent properties result from the specific arrangement and interactions among the component parts. So here's a picture of life's hierarchy of organization.

New properties will emerge at each level. So we kind of have the All these are labeled here, which are kind of hard to see in this picture. So I kind of want to go through one at a time. So we'll talk. So here is an organism.

And an organism is kind of made up of organs and organ systems. And organs and organ systems are made up of tissues. Tissues are made up of cells, which can be made up of organelles.

And organelles are made up of molecules, which are made up of atoms. And I want to take us back through, because I think this first picture, I can, let's see if it makes it a little bigger, kind of explaining everything about this life's hierarchy. So if we start with the biosphere, which includes the entire Earth, and we focus in Florida, we can look at a specific ecosystem, which is a section of Earth's biosphere. at a community, which can contain different populations of species.

And if we look at one organism of species, then we get into what makes up an organism, the organs and organ systems, tissues, cells, the organelles, which are the small tiny organs within cells like the nucleus, and then molecules are made up of atoms, which make up all the organelles. And we'll go through that more as we get into the... chemistry side of things as well.

So that's life's hierarchy, which you have a really should have a very good understanding of which of these levels of biological organization include all of the others in the list, cell, molecule, organ, and tissue. And the organ is the answer to that. So organ includes an organ includes tissues, molecules, and cells.

And the process of science Science is a way of knowing. It's an approach to understanding the natural world. We talked a lot about this in our first lab for the week.

Science uses an evidence-based process of inquiry to investigate the natural world. The scientific approach involves observations, hypotheses, predictions, tests of those hypotheses via experiments or additional observations and analysis of the data. And the scientific theory is broad in scope and support. by a large body of evidence.

So here's a look, kind of an everyday observation. You probably use the scientific method without even realizing it. The flashlight doesn't work.

That's an observation. So the question is, why doesn't the flashlight work? And you could have two hypotheses, which are again, answers to that question.

Hypothesis one, the batteries are dead. Hypothesis two, the bulb is burned out. And then you might go through a series of experiments that have been done to make sure will help you answer that hypothesis.

The prediction might be replacing the batteries. It will fix the problem if the batteries are dead. Or your prediction might be replacing the bulb will fix the problem if the bulb is burned out. So then you'll test both predictions by replacing batteries or replacing the light bulb.

And the results will be the flashlight still doesn't work. So the hypothesis is contradicted. So meaning even when you put in new batteries, the flashlight still isn't working.

Let's see what happens when you replace the light bulb. The flashlight does work. So the hypothesis is supported.

Your hypothesis that said the bulb is burned out was the one that was supported. What's their main requirement for a scientific hypothesis? And again, a hypothesis is just an answer to a question that's formulated because of a problem or observation. And the main requirement for a scientific hypothesis is that it must be able to be tested. by experiments or by gathering further observations.

In some sort of experiment of a hypothesis, researchers will often manipulate one component in a system and observe the effects of that change. The factor that will be manipulated will be the independent variable. The measure used to judge the outcome of the experiment is called the dependent variable, and this variable will depend on the manipulated variable.

and the control experiment will compare an experimental group with the control group. The use of the control and experimental groups can demonstrate the effects of a single variable. For an example, researchers have found that mice models that did not match their habitat had higher predation rates than camouflaged models, and hypotheses can be tested in humans with clinical trials as well as retrospective or prospective observational studies.

And this just shows a beach mouse and an inland mouse with their native habitat looking at how mice look different based on where they live because their camouflage will help keep them safe against predators. The beach population in its native habitat much lighter color to camouflage with the sand versus the inland population mouse again camouflage to help keep it safe from predators. The results from the camouflage experiment, the number of attacks on camouflaged models, and the number of attacks on non-camouflage models, so what this just means is a mice that was not able to camouflage or was taken out of its native habitat had much higher attacks because predators would just be more easily able to spot it. So that's just an example of the scientific method.

Another checkpoint question, in some studies researchers try to match factors such as sex, gender, age, and general health for subjects in the control and experimental groups. What is this experimental design trying to do? And it's trying to ensure that the two groups will differ only in the one variable the experimental is designed to test.

Scientists test hypothesis about the evolutionary relationships of red pandas that we talked a little bit about at the beginning. It's based on observations of physical similarities. Scientists initially hypothesized that the red panda was most closely related to a raccoon, but other scientists who observed their diet and habitat of red pandas said that they're similar to those of giant pandas. So it placed the two pandas together in their own family, but now recent studies compare the DNA sequences of both led scientists to classify red pandas as the only living species of their own family.

So that's what's fun about science. It's constantly changing based on new information and it's always based on facts. It's not based on anyone on opinions.

So again, there were two hypotheses for the group in which red pandas should be classified. One was based on what it physically looks like. So one A group of scientists said we should put it in the group with the raccoons because it looks more like a raccoon based on its physical appearance.

The other group of scientists said, no, based on its diet, it should be paired with the giant pandas. And again, based on their DNA sequences, they've decided that it's its own separate family altogether. Forming and testing hypotheses are at the core of science, and this endeavor is influenced. by exploration and discovery, analysis and feedback from the scientific community. So scientists keep each other in check and make sure they're following the steps correctly of the scientific process and also societal benefits and outcomes.

So how it can help in help animals and humans. So these are kind of more realistic model of the process of science, how kind of all three spheres are working together using hypotheses to form and test theories, but looking at how they benefit society, how other explorations and discoveries will affect these hypotheses and other feedback from the scientific community. Why is hypothesis testing at the center of the process of science? And it's central because it's a core component of science is testable explanations of nature. So remember the main thing that a hypothesis must be is it must be able to be tested.

And that makes sense. If you're going to say something, or if you're going to say a prediction to a problem, you have to be able to test your prediction to be able to see if it's true or not. The goal of science is to understand natural phenomena. In contrast, the goal of technology is to apply scientific knowledge for some specific purpose.

These two fields, however, are independent. Technological advances stem from scientific research and research will benefit from new technologies. Then we'll get into the five unified themes in biology. Life is distinguished by its unity and its diversity.

The scientific explanation or theory for this unity and diversity is evolution, the process of change. That's transformed life on Earth from a... earliest forms to the vast array of organisms living today. And we can see the unity and diversity among birds, all the different types of birds, which is kind of cool.

The American flamingo is my three-year-old's favorite, the hummingbird, and then the penguin. Evolution is the core theme of biology. The theory by Charles Darwin synthesized this theory by natural selection. So he looked at observations and then took inferences from those observations.

Looking at heritable variations and overproduction of offspring led to natural selection, which is an unequal reproductive success leading to evolution of adaptions in certain populations. So here's a population with varied inherited traits. When we eliminate individuals with certain traits and reproduction of survivors, we get an increased frequency of traits that enhance their survival and reproductive success.

So survival of the fittest is key here. Each species on earth today has a family history. A species represents kind of one twig on a branching tree of life that extends back in time, which is more and more remote.

So we kind of see here an evolutionary tree theory of the red panda based on recent molecular data. So it's DNA structure to kind of see where the red panda fits in the family of other animals. Explain the cause and effect of unequal reproductive success.

The answer here, those individuals with heritable traits are best suited to the local environment, will produce the greatest number of offspring. And over many generations, they're prepared to be a part of the family. portions of these adaptive traits increases in the population.

Here's a great video on the blue-footed booby bird courtship ritual, which is really interesting. They have a way of attracting their mates by doing this cool dance. So if you download the PowerPoint, you'll be able to watch this video on your own too. And that owl batras courtship ritual as well.

Evolutionary theory is useful in medicine, conservation, and agriculture. Through the selective breeding of plants and animals, humans also act kind of as agents of evolution by picking out the best and then breeding them together. As a result of artificial selection, our crops, livestock, and pets bear little resemblance to actually their wild ancestors. Explain how humans are agents of both artificial selection and natural selection.

We use artificial selection when choosing specific traits or genes in organisms that we breed, like plants. or animals that was ultimately done to try to provide or increase our food source, especially for developing countries. And our intentional and unintentional manipulations change the environment and thus will affect natural selection. The process of life depends on the transmission and use of information. DNA is what we call the hereditary kind of programming blueprint.

that programs and dictates all activities of the cells for proteins. Information from the external and internal environment includes stimuli, signals, and pathways that regulate body processes and gene expressions. These are the four building blocks of DNA, um, adenine, thymine, cytosine, and guanine. They're nitrogenous bases and they kind of fit together like a puzzle to kind of wind up this DNA in the helical. double-winded strand.

So that's DNA, contains the genetic blueprint building blocks for the proteins in your cells. And the proteins in your cells go on to do all of your cellular processes, which means all of your life processes. So here's a gene X from a DNA strand and gene Y. RNA is transcribed from gene X. So information is kind of put into an RNA strand.

which is then taken to create proteins in a cell. Gene Y is used to make an RNA transcription or a copy of that gene. The information flows to a component of a cell called a ribosome to create protein Y. So we get these different proteins X and Y from different strands on their DNA through a flow of information.

An example of the flow of information. the regulation of the level of glucose in the blood is also important. So a signal in your blood might signal that there's high blood sugar levels or high glucose levels.

In response to that, your pancreas will release insulin and insulin will bind to cells and it'll tell them to pick up extra glucose from your bloodstream to try to get your blood glucose levels back to normal. When that blood glucose levels get back to normal, the insulin levels will drop. Checkpoint question, how is signaling information involved in the expression of genetic information?

Information from your internal and external environment will affect gene expression, where and when particular genes will be activated, and which proteins will be made. Structure and function are related. The relationship between structure and function can be observed at any level of life.

At the molecular level, for example, a protein structure will correlate to its function. So, for example, hemoglobin molecules, it's a protein that has kind of four pieces to it, and it transports oxygen in the blood. On the cellular level, the long extension of your nerve cells will enable them to transmit impulses. incredibly quickly from your spinal cord to your toes. This is a look at the structural adaptations in the form of plant cell walls and insect exoskeletons that function in physical support of an insect.

This is a CT scan showing the false thumb of a red panda and that's just shown here kind of the thumb doesn't exist or it's a lot smaller so it's able to pick up its bamboo a lot more easily. a red panda grasping the bamboo, and the scan showing the false thumb of a red panda. So structure and function are really important. Here's a video about a soaring hawk showing the structure of its wings, showing how it can soar through the air and kind of glide and float. Again a great video to watch, download the PowerPoint and you'll be able to watch all those.

Look at the structure of your hand and explain how its structure supports its function. You'll notice that you have different joints in your fingers and in opposable digits, which allow you to manipulate objects. Opposable digits means your thumb is able to touch your fingers to pick up structures.

Life depends on the transfer and transformation of energy and matter. Energy will flow through an ecosystem in one direction. It will enter as sunlight, be converted to chemical energy by a producer, such as a plant. Then it's passed on to a consumer, some sort of animal or insect that eats the plant, and then it will exit as heat. Ecosystems are characterized by the cycling of matter from the atmosphere and the soil through producers, consumers, and decomposers, which digest waste material, and then back to the environment.

So this just takes you through the flow of energy in an ecosystem. The sun is the ultimate source of light energy. Plants use energy from the sun. to produce food. Leaves take up carbon dioxide from air, roots absorb water and minerals from the soil.

Chemical energy from the food will be taken up by a consumer, an animal, which uses that energy to create, in food, to create its own energy to provide all its processes that it needs to go through. And then the outflow, the flow of energy exits as heat. And decomposers such as worms, fungi, and bacteria will return any sort of chemical back to the soil.

And this is another kind of simple look at the flow of energy, inflow of light energy from the sun going into producers, going into chemical energy, into food, taken up by consumers, and then outflow of heat. And here's the moose as kind of that center part of the animal. Describe how photosynthesis transforms energy and matter.

Photosynthesis uses the energy of sunlight, carbon dioxide, and water to convert into sugar molecules that makes plants, which store chemical energy, which consumers can then eat. The study of life extends from the microscopic scale of molecules and cells that make up an organism to the global scale of a living planet, and emergent properties are the result of interactions between the components of a system. Using an approach that we call systems biology, scientists can attempt to model the behavior of biological systems by analyzing the interactions among their parts.

So for example, a box of bicycle parts won't do anything, but if the parts are properly assembled, you could take a ride. And what does this illustrate? It illustrates the emergent properties of the interacting components of a biological system.

So here's a look at the interactions. among some of the components of an ecosystem, taking a look at that animal. You should now be able to kind of use this kind of these checkpoints at the end of the chapter to test your knowledge based on the chapter. And if you aren't able to do these, you can go back and read the textbook or ask me questions. And here are some of the figures that you can use to kind of double check how you're doing.

Thanks for listening, guys, and we'll see you for the next chapter.

Transcript for:Chapter 1: Biology - Exploring Life

Transcript for:
Chapter 1: Biology - Exploring Life