SNC2D Exam Review Biology - Tissues, Organs, and Organ Systems PDF

SNC2D1 EXAM REVIEW BIOLOGY – Tissues, Organs, and Organ Systems 1. Review the main function of each cellular organelle found in animal and plant cells. Cytoplasm Mostly water Chemical reactions change the consistency from jelly-like to liquid, allowin...

SNC2D1 EXAM REVIEW BIOLOGY – Tissues, Organs, and Organ Systems 1. Review the main function of each cellular organelle found in animal and plant cells. Cytoplasm Mostly water Chemical reactions change the consistency from jelly-like to liquid, allowing organelles to move around. Cell Flexible double - layered surrounding the cell. Membrane Functions to support the cell and allow some substances to enter while keeping others out. Membrane is called a “semi-permeable membrane” Nucleus Contains genetic information that controls all cell activities. Genetic information is stored in the form of chromosomes. Chromosomes are composed of DNA (Deoxyribonucleic acid) DNA carries the coded instructions for all cell activities. DNA must be copied before a cell divides, so that each new cell has a complete set of chromosomes. Mitochondria Singular: mitochondrion Make energy available to the cell, that is stored in glucose molecules. Muscle cells have more mitochondria. Contain enzymes that covert energy stored in glucose. Inner folds called cristae maximize surface area for maximum cellular respiration for energy! Cellular Respiration Equation: Glucose + Oxygen (gas) → Carbon dioxide + Water + energy Endoplasmic A 3D network of branching tubes and pockets. reticulum Extend throughout cytoplasm and is continuous from the nuclear membrane to the cell membrane. (Rough and Rough ER with ribosomes attached making it look “rough”, and Smooth ER without ribosomes. Smooth) Ribosomes* Produce protein Found free floating in the cytoplasm or attached to the Rough Endoplasmic Reticulum (RER) Golgi bodies Singular: Golgi body Collect and process materials to be removed from the cell. Make and secrete (release) mucus. Lysosomes* Produced by Golgi bodies in animal cells only! Contain digestive enzymes that destroy worn out organelles. Play a role in cell death and are sometimes called “suicide sacs” Vacuoles A single layer of membrane enclosing fluid in a sac. Functions include: containing some substances, removing unwanted substances, and maintaining internal fluid pressure (turgor) within the cell. Animal cells have many small vacuoles that are often not visible. Plant cells have one central vacuole that is visible with a microscope. Organelles in Plant Cells Only Cell Wall Found outside of the cell membrane. It is a rigid but porous structure made of cellulose. Vacuole Plant cells have one central vacuole, which takes up most of the space inside the cell. Turgid plant cells: When full of water, turgor pressure keeps the cells plump, which keeps the plant’s stems and leaves firm. Flaccid plant cells: If turgor pressure drops, the stems and leaves become limp and droopy. Chloroplasts Contain a pigment called chlorophyll, which is green in colour. Absorb sunlight energy, used in photosynthesis. Photosynthesis is the process of converting carbon dioxide and water into glucose and oxygen. Photosynthesis Equation: Carbon dioxide + Water + Sunlight energy → Glucose + Oxygen (gas) 2. Explain how the process of cellular respiration and photosynthesis are complementary. The products of cellular respiration are the reactants in photosynthesis. Cellular Respiration Equation: Glucose + Oxygen (gas) → Carbon dioxide + Water + energy Photosynthesis Equation: Carbon dioxide + Water + Sunlight energy → Glucose + Oxygen (gas) 3. Create a graphic organizer comparing the structures of plant and animal cells. Animal Cells Plant Cells Irregular shapes Geometric shapes Lysosomes (suicide sacs) Cell Wall Differences Small vacuoles Large Central Vacuole Chloroplasts Cell membrane, Nucleus, Mitochondria, Endoplasmic Reticulum (Rough & Smooth), Ribosomes, Golgi Similarities bodies, and Vacuoles. 4. Describe what happens during interphase of the cell cycle? Why is this important? Longest stage for most cells. NOT a resting! DNA is replicated (copied or duplicated), so that there are two identical strands. DNA is in very long, thin, invisible threadlike stands called chromatin. More organelles are also formed. 5. Briefly describe the key events in each of the stages of mitosis (PMAT).  Chromatin (threadlike strands of DNA), condenses into a compact form called Prophase chromosomes.  Chromosomes consist of two identical strands called sister chromatids. Each individual stand is called a chromatid.  Sister chromatids are joined by a centromere.  Nuclear membrane dissolves! To allow for the separation of the replicated DNA strands!  Nucleolus disappears.  Spindle fibers begin to develop from centrosome (with centriole pairs).  Chromosomes line up along the middle of the cell called the equatorial or metaphase Metaphase plate.  Spindle fibers stretch from centrosome to centrosome.  Chromosomes attach to spindle fibers by their centromere.  Easiest stage to recognize under the microscope.  Alignment ensures each new daughter cell receives a complete set of chromosomes.  Spindle fibers retract, pulling sister chromatids apart. Anaphase  Centromere splits allowing sister chromatids to separate becoming daughter chromosomes.  Daughter chromosomes move to opposite poles of cell.  Under the microscope, daughter chromosomes appear to be pulled apart and bent.  Daughter chromosomes stretch out, become threadlike again (back to chromatin form). Telophase  Nuclear membrane forms around each group of daughter chromosomes.  Cell appears to have two nuclei.  Nucleolus reappears.  The rest of the cell is ready to divide. 6. What is cellular differentiation? Explain how the different cells (i.e., red blood cells, nerve cells, and muscle cells) in our body are structurally specialized to perform a certain function. Specialized Cell: a cell that can perform a specific function. All cells begin alike and differentiate into specialized cells. All cells start their lives as identical cells called stem cells. Each stem cell can become a specialized cell like a blood cell or skin cell. Each type of cell has different structures and abilities to perform its job. As each cell matures it changes to suit the many different functions that it must do. This process is known as cell differentiation. Red Blood Cells: Smooth to pass through vessels easily. Also, biconcave in shape (depression of both sides) to increase area and maximize oxygen transport. Nerve Cells: Long fiber-like extensions on the cell membrane that carry messages long distances and pick up chemical signals. Muscle Cells: Long and thin which allows them to expand and contract to move bones of the skeleton. 7. Discuss three biological structures (i.e., villi of the small intestine, biconcave red blood cells, and alveoli of the lungs) and how surface area is maximized to perform a specific function. Villi and Microvilli: Folds within the small intestine that increase surface area to allow nutrients to absorb into the bloodstream. Red Blood Cells: Biconcave in shape (depression of both sides) to increase area and maximize oxygen transport. Alveoli: Clusters of cup-shaped air sacs called alveoli (singular: alveolus). Provide enormous surface area for gas exchange. Network of capillaries surrounds each alveolus. Oxygen passes from the alveoli into capillaries. Carbon dioxide passes from the capillaries into alveoli. 8. Create a table to compare each component of blood including the function of each. Plasma Protein-rich liquid that carries the blood cells along. Makes up over half of blood’s volume. Red Make up ½ of the blood’s volume. Blood Protein called hemoglobin, which allows them to transport oxygen throughout the body and makes these Cells cells appear red. Biconcave shape helps to maximize surface area for oxygen transport. Anemia → Lack of healthy RBCs Blood doping → Remove blood from athlete few weeks before competition. Over the course of the following weeks leading to the competition the athlete’s body will undergo mitosis to replace the lost blood cells … levels return to normal. Soon before competition the harvested blood would be injected back into the athlete … more blood than normal. More blood = More RBCs = Increased ability to transport oxygen required for cellular respiration which will in turn create energy needed for the athlete to perform at an enhanced level (greater endurance). White These cells fight infections. Blood Recognize and destroy invading bacteria and viruses. Cells Make up less than 1% of the volume of blood. Only blood cells that have a nucleus. Leukocytosis → % WBCs increases when we are sick to help our body recover. Platelets These are tiny cells that help in blood clotting, which is an essential process of healing wounds. Also comprise less than 1% of blood. Hemophilia → Genetic bleeding disorder in which the blood does not clot properly. 9. What is the main digestive, circulatory, and respiratory systems disorders covered in this unit. Please refer to notes from class. 10. Identify the main structures and functions of the digestive, circulatory, and respiratory systems. Please refer to notes from class.