Cell Transport Quiz - Biology PDF

# Cell Membrane - Homeostasis on the cellular level is maintained by the cell membrane. - The plasma membrane is the outer bilayer of the cell. - It contains: - **phospholipid bilayer**: made up of two layers of phospholipids. Each phospholipid consisting of a phosphate head and t...

# Cell Membrane - Homeostasis on the cellular level is maintained by the cell membrane. - The plasma membrane is the outer bilayer of the cell. - It contains: - **phospholipid bilayer**: made up of two layers of phospholipids. Each phospholipid consisting of a phosphate head and two fatty acid tails. - **nonpolar**: fatty acid tails point inward. - **polar**: phosphate heads point outwards and are hydrophilic. - **cholesterol**: helps maintain the fluidity of the membrane. - **cytoskeleton filaments**: support the membrane. - **proteins**: act as channel or carrier for different molecules and can facilitate diffusion. - **glycoprotein**: acts as a receptor for signaling molecules. - **carbohydrate chain**: for cell recognition. # Selectively Permeable - The cell membrane is selectively permeable which means it's picky about what goes in and out. - **Can pass easily**: - **small** molecules - **nonpolar** molecules - **hydrophobic** molecules - **neutral** molecules - **water** - **Cannot pass easily**: - **polar** molecules - **large** molecules # Words to Know - **Solute**: what gets dissolved (Ex: Lemonade powder) - **Solvent**: does the dissolving (Ex: Water) - **Solution**: uniform mixture of two or more substances (Ex: Lemonade) - **Concentration**: amount of solute dissolved in solvent - Abbreviation = \[] - **Concentration gradient**: Difference in \[] of a substance from one location to another. # Passive Transport - **Passive transport** requires no energy because molecules move from a high concentration (squished together) to a low concentration (spread out) area down the concentration gradient. - **Examples**: simple diffusion, facilitated diffusion, and osmosis. ## Simple Diffusion - The spreading out of molecules across a membrane until equilibrium is reached. - Molecules move down a concentration gradient, from high \[] to an area of low \[] - **Examples**: O₂ and CO₂, and other small, nonpolar molecules. - **Demonstration**: - Over time the molecules will spread out evenly on both sides of the membrane. ## Facilitated Diffusion - A **transport protein** helps to facilitate the diffusion of molecules that normally couldn't pass through the cell membrane. - Transport proteins can act as a **channel** or a **carrier**. - Molecules moves **down a concentration gradient**, high \[] to low \[] - **Examples**: large molecules like glucose (sugar = C₆H₁₂O₆) and polar molecules like calcium (Ca⁺²) - **Demonstration**: - Over time the molecules will spread out evenly on both sides of the membrane with the help of a protein channel. ## Osmosis - The simple diffusion of water across the cell membrane. - **Water** molecules move down a concentration gradient, from high \[water] to an area of low \[water] until equilibrium is reached. - **High [water]** means **low [solute]**. - **Low [water]** means **high [solute]**. - **Demonstration**: - The water passes through a semipermeable membrane from an area of high water concentration with less solutes to an area of low water concentration with higher solutes. ### Types of Osmosis - **Hypertonic Solutions**: Water [] is lower than the cell's cytoplasm - **Net movement of water out of cell** → Cell **shrivels**. - **Hypotonic Solutions**: Water [] is higher than the cell's cytoplasm - **Net movement of water into a cell** → Cell **swells**. - **Isotonic Solutions**: Identical water [] to cell's cytoplasm → Cell **stays the same**. # Pause and Practice ## Hypotonic Solution - **Cell**: 20% NaCl 80% H₂O - **Environment**: 10% NaCl 90% H₂O - **The cell is in a** **hypotonic** **solution** **and will** **swell**. ## Hypertonic Solution - **Cell**: 5% NaCl 95% H₂O - **Environment**: 15% NaCl 85% H₂O - **The cell is in a** **hypertonic** **solution** **and will** **shrivel**. ## Isotonic Solution - **Cell**: 10% NaCl 90% H₂O - **Environment**: 10% NaCl 90% H₂O - **The cell is in a** **isotonic** **solution** **and will** **STAY THE SAME**. # Active Transport - **Active transport** requires energy (ATP) to be used to bring materials into the cell or push materials out of the cell - moving from low to high concentration **against the concentration gradient**. - **Examples**: Molecular pumps, exocytosis, and endocytosis ## Molecular Pumps - When a cell uses energy to pump molecules across the membrane, against the [] gradient, through a protein channel. - This allows a cell to concentrate key molecules within the cell, or remove waste quickly from the cell. - **Examples**: Potassium (K+), chlorine (Cl) and sodium (Na+) = ions. - **Demonstration**: - Molecules will be transported from an area of low concentration to an area of high concentration with help of energy. ## Using Vesicles - **Endocytosis** uses vesicles to move large particles into the cell. - Ex: When white blood cells engulf bacteria in order to fight infection. - **Exocytosis** uses vesicles to export materials out of the cell. - Ex: When nerve cells secrete neurotransmitters to send signals throughout the body. ## 2 Types of Endocytosis - **Phagocytosis**: Cell "eating" - Cell engulfs **solids** into vesicle and "digests" them. - **Pinocytosis**: Cell "drinking" - Cell engulfs **liquids** into vesicle and "digests" them. # Summary | Type of Transport | Passive/Active | Ex. of substances transported this way | |:------------------|:----------------|:---------------------------------------------------| | Facilitated Diffusion| Active | Neurotransmitters | | Endocytosis | Active | Captures bacteria | | | Passive | O₂ and CO₂ | | | Passive | K⁺, Na⁺, Ca²⁺, Cl^- | # Unit Two: Cells ## Concept 1: **Cell Theory and Organelles** - **Objectives**: 1. List the 3 principles of cell theory. 2. Create a Venn Diagram comparing prokaryotic and eukaryotic cells. 3. List the structures that distinguish plant cells from animal cells. 4. Describe the function of the following organelles: cell (plasma) membrane, cytoskeleton, cytoplasm, nucleus, nucleolus, nuclear envelope, ribosomes, endoplasmic reticulum (rough and smooth), vesicle, Golgi apparatus, lysosome, vacuole, centrioles (centrosome), cilia, flagella, mitochondria, chloroplast, and cell wall. 5. Describe the role of proteins, lipids, and carbohydrates in the structure of the phospholipid bilayer. Include how its structure dictates its function. 6. Defend the claim that ribosomes are the most essential organelle in the cell. In your reasoning include evidence of at least 2 organelles that support the ribosome in accomplishing its function for the cell. 7. Explain the concept of endosymbiotic theory and how it relates to mitochondria and chloroplasts. List the evidence that supports endosymbiotic theory. 8. Identify an organelle based on a diagram or description. 9. Identify a cell as eukaryotic, prokaryotic, plant, or animal based on a description or diagram. 10. Predict the consequences of the failure or absence of an organelle inside a eukaryotic cell. - **Vocabulary**: Unicellular, Multicellular, Organelle ## Concept 2: **Cell Transport** - **Objectives**: 1. Differentiate between dynamic and static equilibrium with regards to homeostasis. 2. Describe the relationship between a response to stimuli and homeostasis. 3. Differentiate between positive and negative feedback loops. Include two examples of each. 4. Explain the role of the cell membrane in maintaining homeostasis on a cellular level. Include which substances can and cannot pass through easily. 5. Differentiate between passive and active transport. 6. Describe (either with words or drawings) the six types of transport. List examples of substances transported via each method. 7. Explain the difference between hypotonic, isotonic, and hypertonic solutions. You may use a picture to help you describe. 8. Classify a type of cell transport as active or passive based on a diagram or description. 9. Infer which type of cell transport would be best suited to move a given substance across the cell membrane based on a diagram or description. 10. Classify solutions as hypertonic, hypotonic, or isotonic based on a diagram or description. - **Vocabulary**: Solute, Solvent, Solution, Concentration, Concentration gradient, Phagocytosis, Pinocytosis ## Concept 3: **Cell Cycle and Cancer** - **Objectives**: 1. Explain the difference between specialized cells and stem cells. 2. List the levels of organization from cell to organism that result from differentiation. 3. List the two main purposes for cell division. 4. Sketch and label a homologous chromosome pair before and after S phase. Include a brief description of the importance of S phase. 5. Describe ALL PHASES of the cell cycle, including the phases in interphase and mitosis, in order. 6. Differentiate between cytokinesis in plants and animal cells. 7. Summarize how cells know when they need to divide. Include examples of the difference between internal and external regulation. 8. Explain the key roles of checkpoints and apoptosis in the regulation of the cell cycle. 9. Define tumor and differentiate between the two types. 10. List several potential causes of cancer. 11. Identify what stage of mitosis a cell is in based on a description or diagram. 12. Predict consequences of a failure during a given phase of the cell cycle. - **Vocabulary**: Differentiation, Stem cells, Cell cycle, Chromosome, Gene, Sister chromatids, Centromere, Telomere, Cancer, Metastasize, Carcinogens