Which Cell Parts Are Common To Plant And Animal Cells Chapter 7 Section 7.3

Learning Objectives

In this section, you will explore the following questions:

• How does the structure of the eukaryotic cell resemble as well every bit differ from the structure of the prokaryotic jail cell?
• What are structural differences between animal and plant cells?
• What are the functions of the major cell structures?

Connection for AP^® Courses

Eukaryotic cells possess many features that prokaryotic cells lack, including a nucleus with a double membrane that encloses DNA. In addition, eukaryotic cells tend to be larger and have a variety of membrane-bound organelles that perform specific, compartmentalized functions. Evidence supports the hypothesis that eukaryotic cells likely evolved from prokaryotic ancestors; for example, mitochondria and chloroplasts feature characteristics of independently-living prokaryotes. Eukaryotic cells come in all shapes, sizes, and types (eastward.g. animal cells, plant cells, and unlike types of cells in the body). (Hint: This a rare instance where you should create a list of organelles and their respective functions because later you will focus on how diverse organelles work together, similar to how your body'south organs piece of work together to keep y'all healthy.) Like prokaryotes, all eukaryotic cells have a plasma membrane, cytoplasm, ribosomes, and DNA. Many organelles are spring by membranes equanimous of phospholipid bilayers embedded with proteins to compartmentalize functions such as the storage of hydrolytic enzymes and the synthesis of proteins. The nucleus houses Dna, and the nucleolus within the nucleus is the site of ribosome assembly. Functional ribosomes are establish either free in the cytoplasm or attached to the rough endoplasmic reticulum where they perform protein synthesis. The Golgi apparatus receives, modifies, and packages pocket-size molecules like lipids and proteins for distribution. Mitochondria and chloroplasts participate in gratis energy capture and transfer through the processes of cellular respiration and photosynthesis, respectively. Peroxisomes oxidize fatty acids and amino acids, and they are equipped to intermission downward hydrogen peroxide formed from these reactions without letting it into the cytoplasm where it can cause impairment. Vesicles and vacuoles shop substances, and in plant cells, the key vacuole stores pigments, salts, minerals, nutrients, proteins, and degradation enzymes and helps maintain rigidity. In contrast, animal cells take centrosomes and lysosomes but lack cell walls.

Data presented and the examples highlighted in the department support concepts and Learning Objectives outlined in Large Idea 1, Big Idea 2, and Big Thought four of the AP^® Biological science Curriculum Framework. The Learning Objectives listed in the Curriculum Framework provide a transparent foundation for the AP^® Biology course, an inquiry-based laboratory experience, instructional activities, and AP^® exam questions. A Learning Objective merges required content with ane or more than of the vii Scientific discipline Practices.

Big Idea i	The procedure of evolution drives the diversity and unity of life.
Enduring Understanding 1.B	Organisms are linked past lines of descent from common ancestry
Essential Cognition	1.B.1 Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.
Scientific discipline Practise	7.ii The student can connect concepts in and across domains to generalize or extrapolate in and/or across enduring understandings
Learning Objective	1.15 The student is able to describe specific examples of conserved core biological processes and features shared past all domains or inside i domain of life and how these shared, conserved core processes and features support the concept of mutual ancestry for all organisms.
Big Thought ii	Biological systems utilize costless energy and molecular building blocks to grow, to reproduce and to maintain dynamic homeostasis.
Indelible Agreement 2.B	Growth, reproduction and dynamic homeostasis crave that cells create and maintain internal environments that are different from their external environments.
Essential Noesis	2.B.3 Eukaryotic cells maintain internal membranes that partition the prison cell into specialized regions.
Science Practice	6.ii The student tin construct explanations of phenomena based on testify produced through scientific practices.
Learning Objective	2.13 The student is able to explain how internal membranes and organelles contribute to cell functions.
Essential Noesis	2.B.3 Eukaryotic cells maintain internal membranes that partition the prison cell into specialized regions.
Science Practice	1.4 The student tin use representations and models to analyze situations or solve bug qualitatively and quantitatively.
Learning Objective	2.14 The student is able to apply representations and models to draw differences in prokaryotic and eukaryotic cells.
Big Idea iv	Biological systems interact, and these systems and their interactions possess complex backdrop.
Enduring Understanding iv.A	Interactions inside biological systems lead to complex properties.
Essential Knowledge	four.A.2 The structure and function of subcellular components, and their interactions, provide essential cellular processes.
Science Practice	6.ii The pupil can construct explanations of phenomena based on evidence produced through scientific practices.
Learning Objective	4.5 The educatee is able to construct explanations based on scientific evidence as to how interactions of subcellular structures provide essential functions.

Teacher Support

Divide students into groups of 4–5 and assign each group either a bacterial, constitute or animate being cell and ask each grouping to describe the cell and its components on a large canvas of paper. Groups will use a separate canvas of newspaper to list all the structures and their corresponding functions. Ask each group to nowadays its cell model to the residuum of the class. Post the drawings on the wall of the class. Update the models with corrections as needed.

Many students reason that establish cells do not need mitochondria because the chloroplasts within found cells convert light energy into chemical energy, and, therefore, mitochondria are non needed. Stress that all eukaryotic cells (with simply few exceptions) comprise mitochondria.

Emphasize that the diagrams in the textbook represent generalizations. Cells vary enormously in shapes and functions. Some internal structures may be predominant co-ordinate to the blazon of jail cell. For instance, liver cells that detoxify chemicals and synthesize lipids have an extensive smooth endoplasmic reticulum.

The Scientific discipline Practice Challenge Questions contain additional test questions for this section that will help you set for the AP exam. These questions address the following standards:
[APLO 1.15] [APLO ii.5][APLO 2.25][APLO i.16]

Have you ever heard the phrase "form follows function?" It'southward a philosophy skillful in many industries. In architecture, this means that buildings should exist synthetic to support the activities that volition be carried out inside them. For example, a skyscraper should be built with several elevator banks; a hospital should be built so that its emergency room is easily attainable.

Our natural world also utilizes the principle of course following function, peculiarly in cell biology, and this will become clear every bit we explore eukaryotic cells (Figure 4.8). Unlike prokaryotic cells, eukaryotic cells take: 1) a membrane-leap nucleus; 2) numerous membrane-bound organelles such as the endoplasmic reticulum, Golgi appliance, chloroplasts, mitochondria, and others; and 3) several, rod-shaped chromosomes. Because a eukaryotic cell'southward nucleus is surrounded by a membrane, it is oftentimes said to accept a "true nucleus." The give-and-take "organelle" means "piddling organ," and, as already mentioned, organelles have specialized cellular functions, simply equally the organs of your body have specialized functions.

At this point, it should be clear to yous that eukaryotic cells have a more complex structure than prokaryotic cells. Organelles let different functions to be compartmentalized in different areas of the cell. Before turning to organelles, let'due south first examine two important components of the cell: the plasma membrane and the cytoplasm.

Visual Connection

Figure 4.8 These figures bear witness the major organelles and other cell components of (a) a typical animal prison cell and (b) a typical eukaryotic plant prison cell. The plant prison cell has a cell wall, chloroplasts, plastids, and a fundamental vacuole—structures not establish in animate being cells. About plant cells do not have lysosomes or centrosomes.

If the nucleolus were not able to carry out its role, what other cellular organelles would exist affected?

1. The structure of endoplasmic reticulum would non form.

2. The function of lysosomes would exist hindered, equally hydrolases are formed past nucleolus.

3. The gratis ribosomes and the rough endoplasmic reticulum, which contains ribosomes, would not form.

4. The Golgi apparatus volition not be able to sort proteins properly.

The Plasma Membrane

Like prokaryotes, eukaryotic cells take a plasma membrane (Figure 4.nine), a phospholipid bilayer with embedded proteins that separates the internal contents of the cell from its surrounding environment. A phospholipid is a lipid molecule with ii fatty acid chains and a phosphate-containing grouping. The plasma membrane controls the passage of organic molecules, ions, water, and oxygen into and out of the cell. Wastes (such as carbon dioxide and ammonia) besides leave the cell by passing through the plasma membrane.

Figure iv.9 The eukaryotic plasma membrane is a phospholipid bilayer with proteins and cholesterol embedded in it.

The plasma membranes of cells that specialize in assimilation are folded into fingerlike projections called microvilli (singular = microvillus); (Effigy 4.10). Such cells are typically found lining the small-scale intestine, the organ that absorbs nutrients from digested food. This is an first-class example of form following function. People with celiac affliction take an immune response to gluten, which is a protein found in wheat, barley, and rye. The immune response damages microvilli, and thus, afflicted individuals cannot absorb nutrients. This leads to malnutrition, cramping, and diarrhea. Patients suffering from celiac affliction must follow a gluten-free diet.

Figure 4.10 Microvilli, shown here as they appear on cells lining the small intestine, increment the surface area available for absorption. These microvilli are but constitute on the area of the plasma membrane that faces the cavity from which substances will be absorbed. (credit "micrograph": modification of work by Louisa Howard)

The Cytoplasm

The cytoplasm is the entire region of a cell between the plasma membrane and the nuclear envelope (a construction to exist discussed soon). Information technology is made up of organelles suspended in the gel-similar cytosol, the cytoskeleton, and diverse chemicals (Figure four.eight). Even though the cytoplasm consists of 70 to eighty percent h2o, information technology has a semi-solid consistency, which comes from the proteins within it. However, proteins are not the only organic molecules plant in the cytoplasm. Glucose and other simple sugars, polysaccharides, amino acids, nucleic acids, fatty acids, and derivatives of glycerol are found there, too. Ions of sodium, potassium, calcium, and many other elements are also dissolved in the cytoplasm. Many metabolic reactions, including protein synthesis, take place in the cytoplasm.

The Nucleus

Typically, the nucleus is the nigh prominent organelle in a cell (Figure 4.eight). The nucleus (plural = nuclei) houses the cell's Deoxyribonucleic acid and directs the synthesis of ribosomes and proteins. Let'south expect at information technology in more detail (Figure iv.eleven).

Figure 4.11 The nucleus stores chromatin (Deoxyribonucleic acid plus proteins) in a gel-like substance chosen the nucleoplasm. The nucleolus is a condensed region of chromatin where ribosome synthesis occurs. The boundary of the nucleus is called the nuclear envelope. It consists of two phospholipid bilayers: an outer membrane and an inner membrane. The nuclear membrane is continuous with the endoplasmic reticulum. Nuclear pores allow substances to enter and exit the nucleus.

The Nuclear Envelope

The nuclear envelope is a double-membrane structure that constitutes the outermost portion of the nucleus (Effigy 4.11). Both the inner and outer membranes of the nuclear envelope are phospholipid bilayers.

The nuclear envelope is punctuated with pores that control the passage of ions, molecules, and RNA between the nucleoplasm and cytoplasm. The nucleoplasm is the semi-solid fluid inside the nucleus, where we find the chromatin and the nucleolus.

Chromatin and Chromosomes

To understand chromatin, it is helpful to beginning consider chromosomes. Chromosomes are structures within the nucleus that are made upwards of DNA, the hereditary material. You may remember that in prokaryotes, Deoxyribonucleic acid is organized into a single circular chromosome. In eukaryotes, chromosomes are linear structures. Every eukaryotic species has a specific number of chromosomes in the nucleus of each cell. For example, in humans, the chromosome number is 46, while in fruit flies, it is eight. Chromosomes are but visible and distinguishable from one another when the prison cell is getting ready to divide. When the cell is in the growth and maintenance phases of its life cycle, proteins are attached to chromosomes, and they resemble an unwound, jumbled bunch of threads. These unwound protein-chromosome complexes are called chromatin (Effigy 4.12); chromatin describes the material that makes up the chromosomes both when condensed and decondensed.

Effigy four.12 (a) This image shows diverse levels of the organization of chromatin (Dna and protein). (b) This image shows paired chromosomes. (credit b: modification of work by NIH; scale-bar data from Matt Russell)

The Nucleolus

Nosotros already know that the nucleus directs the synthesis of ribosomes, but how does it do this? Some chromosomes have sections of DNA that encode ribosomal RNA. A darkly staining area within the nucleus called the nucleolus (plural = nucleoli) aggregates the ribosomal RNA with associated proteins to assemble the ribosomal subunits that are then transported out through the pores in the nuclear envelope to the cytoplasm.

Ribosomes

Ribosomes are the cellular structures responsible for protein synthesis. When viewed through an electron microscope, ribosomes appear either equally clusters (polyribosomes) or single, tiny dots that float freely in the cytoplasm. They may exist attached to the cytoplasmic side of the plasma membrane or the cytoplasmic side of the endoplasmic reticulum and the outer membrane of the nuclear envelope (Figure 4.8). Electron microscopy has shown us that ribosomes, which are large complexes of protein and RNA, consist of ii subunits, aptly called big and pocket-sized (Figure 4.xiii). Ribosomes receive their "orders" for protein synthesis from the nucleus where the DNA is transcribed into messenger RNA (mRNA). The mRNA travels to the ribosomes, which translate the code provided by the sequence of the nitrogenous bases in the mRNA into a specific guild of amino acids in a protein. Amino acids are the edifice blocks of proteins.

Figure iv.13 Ribosomes are made up of a big subunit (top) and a small subunit (bottom). During protein synthesis, ribosomes gather amino acids into proteins.

Because protein synthesis is an essential function of all cells (including enzymes, hormones, antibodies, pigments, structural components, and surface receptors), ribosomes are found in practically every cell. Ribosomes are particularly abundant in cells that synthesize big amounts of poly peptide. For example, the pancreas is responsible for creating several digestive enzymes and the cells that produce these enzymes contain many ribosomes. Thus, nosotros see another instance of form following function.

Mitochondria

Mitochondria (atypical = mitochondrion) are often chosen the "powerhouses" or "free energy factories" of both plant and brute cells considering they are responsible for making adenosine triphosphate (ATP), the prison cell'southward main energy-conveying molecule. ATP represents the short-term stored free energy of the cell. Cellular respiration is the procedure of making ATP using the chemical free energy found in glucose and other nutrients. In mitochondria, this process uses oxygen and produces carbon dioxide equally a waste matter product. In fact, the carbon dioxide that you exhale with every breath comes from the cellular reactions that produce carbon dioxide equally a byproduct.

In keeping with our theme of form following part, it is important to point out that musculus cells take a very high concentration of mitochondria that produce ATP. Your muscle cells demand a lot of energy to keep your body moving. When your cells don't become enough oxygen, they exercise not make a lot of ATP. Instead, the small amount of ATP they make in the absence of oxygen is accompanied by the production of lactic acid.

Mitochondria are oval-shaped, double membrane organelles (Figure 4.14) that have their own ribosomes and Deoxyribonucleic acid. Each membrane is a phospholipid bilayer embedded with proteins. The inner layer has folds called cristae. The expanse surrounded past the folds is called the mitochondrial matrix. The cristae and the matrix have different roles in cellular respiration.

Figure 4.xiv This electron micrograph shows a mitochondrion every bit viewed with a transmission electron microscope. This organelle has an outer membrane and an inner membrane. The inner membrane contains folds, chosen cristae, which increment its surface surface area. The infinite between the two membranes is called the intermembrane space, and the space inside the inner membrane is called the mitochondrial matrix. ATP synthesis takes identify on the inner membrane. (credit: modification of work by Matthew Britton; scale-bar data from Matt Russell)

Peroxisomes

Peroxisomes are small, round organelles enclosed past unmarried membranes. They carry out oxidation reactions that break down fatty acids and amino acids. They as well detoxify many poisons that may enter the trunk. (Many of these oxidation reactions release hydrogen peroxide, H₂O₂, which would be damaging to cells; however, when these reactions are bars to peroxisomes, enzymes safely break downward the H₂O_ii into oxygen and h2o.) Glyoxysomes, which are specialized peroxisomes in plants, are responsible for converting stored fats into sugars.

Vesicles and Vacuoles

Vesicles and vacuoles are membrane-bound sacs that function in storage and ship. Other than the fact that vacuoles are somewhat larger than vesicles, there is a very subtle distinction between them: The membranes of vesicles tin can fuse with either the plasma membrane or other membrane systems within the jail cell. Additionally, some agents such as enzymes inside plant vacuoles break downwardly macromolecules. The membrane of a vacuole does non fuse with the membranes of other cellular components.

Creature Cells versus Plant Cells

At this point, you know that each eukaryotic cell has a plasma membrane, cytoplasm, a nucleus, ribosomes, mitochondria, peroxisomes, and in some, vacuoles, but there are some striking differences between animate being and institute cells. While both animal and plant cells have microtubule organizing centers (MTOCs), creature cells besides have centrioles associated with the MTOC: a complex called the centrosome. Animal cells each have a centrosome and lysosomes, whereas most constitute cells exercise not. Plant cells take a cell wall, chloroplasts and other specialized plastids, and a large fundamental vacuole, whereas animate being cells do non.

The Centrosome

The centrosome is a microtubule-organizing center establish near the nuclei of animal cells. It contains a pair of centrioles, two structures that lie perpendicular to each other (Effigy 4.xv). Each centriole is a cylinder of nine triplets of microtubules.

Figure 4.15 The centrosome consists of ii centrioles that lie at right angles to each other. Each centriole is a cylinder made up of 9 triplets of microtubules. Nontubulin proteins (indicated past the green lines) hold the microtubule triplets together.

The centrosome (the organelle where all microtubules originate) replicates itself before a cell divides, and the centrioles appear to have some office in pulling the duplicated chromosomes to opposite ends of the dividing cell. However, the exact function of the centrioles in prison cell division isn't clear, because cells that have had the centrosome removed can notwithstanding divide, and found cells, which lack centrosomes, are capable of cell division.

Lysosomes

Beast cells have another set of organelles not plant in most institute cells: lysosomes. The lysosomes are the jail cell's "garbage disposal." In institute cells, the digestive processes take place in vacuoles. Enzymes within the lysosomes assist the breakdown of proteins, polysaccharides, lipids, nucleic acids, and fifty-fifty worn-out organelles. These enzymes are active at a much lower pH than that of the cytoplasm. Therefore, the pH within lysosomes is more acidic than the pH of the cytoplasm. Many reactions that accept place in the cytoplasm could not occur at a depression pH, so again, the reward of compartmentalizing the eukaryotic cell into organelles is credible.

The Cell Wall

If you examine Effigy 4.8b, the diagram of a plant prison cell, you will see a structure external to the plasma membrane called the prison cell wall. The cell wall is a rigid covering that protects the jail cell, provides structural support, and gives shape to the jail cell. Fungal and protistan cells also have cell walls. While the chief component of prokaryotic jail cell walls is peptidoglycan, the major organic molecule in the constitute cell wall is cellulose (Effigy 4.sixteen), a polysaccharide made up of glucose units. Have you lot e'er noticed that when yous bite into a raw vegetable, like celery, it crunches? That's considering you are tearing the rigid prison cell walls of the celery cells with your teeth.

Figure 4.xvi Cellulose is a long chain of β-glucose molecules connected by a 1-4 linkage. The dashed lines at each stop of the effigy indicate a series of many more glucose units. The size of the page makes it incommunicable to portray an entire cellulose molecule.

Chloroplasts

Similar the mitochondria, chloroplasts have their own DNA and ribosomes, but chloroplasts have an entirely different function. Chloroplasts are establish jail cell organelles that comport out photosynthesis. Photosynthesis is the series of reactions that use carbon dioxide, h2o, and light free energy to make glucose and oxygen. This is a major departure between plants and animals; plants (autotrophs) are able to make their ain nutrient, similar sugars used in cellular respiration to provide ATP energy generated in the institute mitochondria. Animals (heterotrophs) must ingest their nutrient.

Like mitochondria, chloroplasts have outer and inner membranes, but within the infinite enclosed past a chloroplast's inner membrane is a set of interconnected and stacked fluid-filled membrane sacs called thylakoids (Effigy iv.17). Each stack of thylakoids is called a granum (plural = grana). The fluid enclosed past the inner membrane that surrounds the grana is called the stroma.

Figure 4.17 The chloroplast has an outer membrane, an inner membrane, and membrane structures called thylakoids that are stacked into grana. The space within the thylakoid membranes is called the thylakoid space. The light harvesting reactions accept place in the thylakoid membranes, and the synthesis of sugar takes place in the fluid inside the inner membrane, which is called the stroma. Chloroplasts also have their own genome, which is contained on a single circular chromosome.

The chloroplasts contain a green pigment called chlorophyll, which captures the calorie-free energy that drives the reactions of photosynthesis. Like plant cells, photosynthetic protists also take chloroplasts. Some bacteria perform photosynthesis, but their chlorophyll is non relegated to an organelle.

Development Connection

Endosymbiosis

We take mentioned that both mitochondria and chloroplasts contain DNA and ribosomes. Have you wondered why? Strong evidence points to endosymbiosis as the explanation.

Symbiosis is a relationship in which organisms from 2 separate species depend on each other for their survival. Endosymbiosis (endo- = "within") is a mutually beneficial human relationship in which one organism lives inside the other. Endosymbiotic relationships abound in nature. We have already mentioned that microbes that produce vitamin K live within the homo gut. This relationship is beneficial for united states because we are unable to synthesize vitamin K. It is likewise beneficial for the microbes because they are protected from other organisms and from drying out, and they receive abundant food from the environment of the large intestine.

Scientists have long noticed that bacteria, mitochondria, and chloroplasts are like in size. We besides know that bacteria have Deoxyribonucleic acid and ribosomes, just as mitochondria and chloroplasts practice. Scientists believe that host cells and bacteria formed an endosymbiotic human relationship when the host cells ingested both aerobic and autotrophic bacteria (blue-green alga) but did not destroy them. Through many millions of years of evolution, these ingested bacteria became more specialized in their functions, with the aerobic bacteria becoming mitochondria and the autotrophic bacteria becoming chloroplasts.

Based on what you know most plant and animals cells, which of the following events are most probable to accept occurred?

1. A host cell that ingested aerobic bacteria gave rise to mod animals, while ancestor of that cell that also ingested photoautotrophic leaner that gave rise to mod plants.

2. A host cell that gave rise to mod plants ingested photoautotrophic bacteria just, while a host cell that gave rise to modern animals ingested aerobic bacteria only.

3. A host cell that gave ascent to modern plants ingested both aerobic and photoautotrophic bacteria, while a host cell that gave rise to modern animals ingested photoautotrophic bacteria only.

4. A host cell that gave ascension to modern plants and animals ingested both aerobic and photoautotrophic bacteria.

The Cardinal Vacuole

Previously, we mentioned vacuoles as essential components of constitute cells. If you look at Figure 4.8b, yous will see that plant cells each have a large central vacuole that occupies nigh of the area of the cell. The central vacuole plays a key role in regulating the prison cell's concentration of water in changing environmental weather condition. Accept you always noticed that if y'all forget to water a institute for a few days, information technology wilts? That'southward considering as the water concentration in the soil becomes lower than the water concentration in the establish, water moves out of the central vacuoles and cytoplasm. Equally the central vacuole shrinks, it leaves the jail cell wall unsupported. This loss of back up to the prison cell walls of institute cells results in the wilted appearance of the institute.

The central vacuole also supports the expansion of the jail cell. When the fundamental vacuole holds more water, the cell gets larger without having to invest a lot of free energy in synthesizing new cytoplasm.

Science Practice Connection for AP® Courses

Activeness

• Construct a concept map or Venn diagram to describe the relationships that exist amongst the three domains of life (Archaea, Bacteria, and Eukarya) based on cellular features. Share your diagram with other students in the course for review and revision.
• Mystery Cell ID. Using a microscope, identify several types of cells, e.g., prokaryote/eukaryote, plant/creature, based on general features and justify your identification.
• X-Minute Debate. Working in pocket-size teams, create a visual representation to support the merits that eukaryotes evolved from symbiotic relationships amidst groups of prokaryotes.

Think About It

• If the nucleolus were not able to deport out its function, what other cellular organelles would be affected? Would a human liver prison cell that lacked endoplasmic reticulum be able to metabolize toxins?

• Antibiotics are medicines that are used to fight bacterial infections. These medicines kill prokaryotic cells without harming man cells. What function(s) of the bacterial jail cell do antibiotics target and provide reasoning for your answer.

Instructor Support

The first activity is an awarding of Learning Objectives one.fifteen and Science Practice 7.2 because students are describing features mutual to all cells that suggest mutual ancestry.

The 2d activity is an application of Learning Objectives 2.14 and Science Practise 1.4 because the students are describing features that typify various cell types based on models presented in the textbook.

The third action is an application of Learning Objectives 1.16 and Scientific discipline Practice six.i because the students are describing bear witness that supports the merits that eukaryotes evolved from prokaryotes. and following with a question that could exist investigated to provide additional support for this claim.

The first question is an application of Learning Objectives iv.4 and Science Practice 6.iv because the students are asked to make predictions about the functions of cellular organelles.

The second question is an application of Learning Objectives 2.14 and Science Practice 1.4 because the students are describing differences betwixt prokaryotic and eukaryotic cells based on models of the cell(s).

Although ribosomes are well-conserved, there are plenty differences between prokaryotic and eukaryotic ribosomes that many antibiotics target the prokaryotic ribosomes without affecting the eukaryotic ribosomes. Mention that ribosomes in mitochondria and chloroplasts are very like to the prokaryotic ribosomes. This is a potent signal in support of the endosymbiotic theory.

Cull a light or electron microscope or set of micrographs to extend the activity. This enables the students to have size into consideration. Employ table 4.i every bit a guide. Point out that eventually all organelles would be affected by a loss of ribosome function, as protein synthesis shuts down.

• A human liver cell that lacked the polish endoplasmic reticulum (SER) would not breakdown toxins, equally that is one of the functions of the SER. This is an opportunity to differentiate between RER and SER.
• All antibiotics inhibit growth either by killing (bactericidal) or past interfering with growth (bacteriostatic). Penicillin and derivatives inhibit the synthesis of peptidoglycans in the cell wall. Without a jail cell wall, bacterial cells lyse.

Source: https://openstax.org/books/biology-ap-courses/pages/4-3-eukaryotic-cells

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