W1_GB1_The Role of ATP and Plant Pigments PDF

A Lesson Presentation by Sebaste High School Joenas C. Tunguia General Biology 1 | Teacher II 2024 THE ROLE OF ATP AND THE IMPORTANCE OF PLANT PIGMENTS Q2_Module 1 CHECKING OF ATTENDANCE LEARNI...

A Lesson Presentation by Sebaste High School Joenas C. Tunguia General Biology 1 | Teacher II 2024 THE ROLE OF ATP AND THE IMPORTANCE OF PLANT PIGMENTS Q2_Module 1 CHECKING OF ATTENDANCE LEARNING COMPETENCIES ❖ Explain coupled reaction processes and describe Give a brief overview of what you’ll cover in your presentation. the role of ATP in energy coupling and transfer (STEM_BIO11/12-IIa-j-1) ❖ Explain the importance of chlorophyll and other pigments (STEM_BIO11/12-IIa-j-3) PRE-ACTIVITY Situation: Suppose you have two rechargeable batteries. Give a brief overview of what you’ll cover in your presentation. One is fully charged and the other one is almost empty. You inserted each battery in each of the two flashlights. Predict what will happen to the light emitted in the two flashlights. Draw your predictions for A and B and write your answers in your notebook. DISCUSSION: Energy is essential to life. All living things must be able to produce Give a briefenergy, store overview of what you’ll energy for future use, and use energy to cover in your presentation. carry out life processes. In everyday life, energy is important because it can be used to do work such as eating, walking, running, talking, and thinking or simply turning the pages of this learning material. Some cellular activities that require energy are active transport, protein synthesis, and cell division. Energy can exist or be stored in many forms such as light, heat, electricity, and chemical bonds in chemical compounds. ATP STRUCTURE AND HYDROLYSIS How do organisms carry out essential life processes? Cells in Give a brief overview organisms obtainof whatenergy you’ll cover infrom your presentation. the chemical bonds that hold together certain organic compounds, such as carbohydrates from the food that we eat. This energy in turn is used to produce adenosine triphosphate (ATP). ATP is an organic molecule used for short-term energy storage and transport in the cell. It is composed of three parts: (1) a nitrogenous base (adenine), a sugar (ribose), and three phosphate groups (triphosphate)  Structure of an ATP molecule Give a brief overview of what you’ll cover in your presentation. DISCUSSION The three phosphate groups in an ATP molecule are negatively charged. Give a brief overview of what Recall that you’ll cover in molecules having the same charge your presentation. will tend to repel from each other. Thus, this means that the three phosphate groups are in an unstable arrangement. The third phosphate group is so eager to get further away from the two phosphate groups. A bond between them is broken through hydrolysis (water-mediated breakdown) reaction releasing energy (Figure 2). The remaining free phosphate group and low-energy molecule is called adenosine diphosphate (ADP). Give a brief overview of what you’ll cover in your presentation. ATP-ADP Cycle The hydrolysis of ATP to ADP is reversible (Figure 3). Give a brief overview of what you’ll cover in your presentation. ATP and ADP are like charged and uncharged forms of a rechargeable battery. ATP (charged battery) has energy that can be used to power cellular processes or reactions. Once the energy is used up, ADP (uncharged battery/dead battery) needs to be recharged in order to be used as a power source. ATP-ADP Cycle ATP regeneration reaction is the reverse of hydrolysis Give a brief overview of what you’ll cover in your presentation. reaction: \text{energy} + \text{ADP} + \text P_i \leftrightharpoons \text{ATP} + \text{H} _2 \text{O} Give a brief overview of what you’ll cover in your presentation. ATP-ADP Cycle Remember Give a brief overview of what you’ll cover in your presentation. When ATP is broken down, energy is released and ADP is formed. When ADP binds with another phosphate group, energy is stored and ATP is formed. ATP in Energy Coupling How is the energy released by ATP hydrolysis used to power cells to carry out useful functions? Give a brief overview of what you’ll cover in your presentation. The hydrolysis of ATP not only results to a release of energy but also would simply result in organisms’ overheating because the dissipation of energy would excite nearby molecules, resulting in heat or thermal energy. Energy in a cell needs to be linked to other processes in order to be useful. Energy coupling is the transfer of energy from one chemical reaction to another. An energetically favorable reaction (exergonic, e.g., ATP hydrolysis) is directly linked with an energetically unfavorable reaction (endergonic, e.g., ATP regeneration). Through energy coupling, the cell can perform nearly all of the tasks it needs to function. ATP in Energy Coupling Chemical reactions can be classified as either Give a brief overview of what you’ll cover in your presentation. exergonic (energy outward) or endergonic (energy inward) (Figure 4): Exergonic reaction - proceeds with a net release of free energy Endergonic reaction - one that absorbs free energy from its surroundings ATP in Energy Coupling Give a brief overview of what you’ll cover in your presentation. ATP in Energy Coupling One example of energy coupling involving ATP is the formation of sucrose (tableof sugar) Give a brief overview from what you’ll cover glucose in your and fructose (Figure 5). In the presentation. uncoupled reaction, glucose and fructose combine to form sucrose. In the coupled reaction, there are two reactions that take place: 1. A phosphate group is transferred from ATP to glucose, forming a phosphorylated glucose intermediate (glucose-P). This is an energetically favorable reaction or exergonic reaction. 2. The glucose-P intermediate reacts with fructose to form sucrose. Because glucose-P is relatively unstable, this reaction also releases energy and is spontaneous. This example shows how reaction coupling involving ATP can work through phosphorylation, breaking a reaction down into two energetically favored steps connected by a phosphorylated (phosphate- bearing) intermediate. This strategy is used in many metabolic pathways in the cell, providing a way for the energy released by converting ATP to ADP to drive other reactions forward. The Importance of Chlorophyll and Other Pigments Light from the sun is absorbed by colorful Give a brief overview of what you’ll cover in your presentation. compounds or visible light is called pigments. The structure and amount of pigments determine the variations in color. The chlorophyll pigment in leaves helps make photosynthesis happen by absorbing light energy from the sun to put together carbon dioxide and water to form glucose or food. The Importance of Chlorophyll and Other Pigments All colors of visible light except green are absorbed by Give a brief overview of what you’ll cover in your presentation. chlorophyll, which it reflects to be detected by our eyes. Chlorophyll gives plants their green color and may hide the other pigments found in leaves. If all colors or wavelengths of visible light are absorbed and none are reflected, the pigment appears black to our eyes. On the contrary, if all colors or wavelengths of light are reflected, the pigment appears white to our eyes. Chlorophyll and Accessory Pigments Green plants have green leaves, and the leaves are Give a brief overview of what you’ll cover in your presentation. green because of the green pigment called chlorophyll, which are found in the chloroplasts. The visible light spectrum ranges from red (the longest wavelength) to orange, yellow, green, blue, indigo, and violet (the shortest wavelength). Plants possess pigments that can absorb light in specific regions of the spectrum (Figure 6). Chlorophyll and Accessory Pigments Chlorophylls appear green because the pigments absorb light on all of the color Give a brief overview of what you’ll cover in your presentation. ranges, and only green is transmitted to our eyes. Chlorophyll a is the core pigment that absorbs sunlight for light-dependent photosynthesis. It readily absorbs violet/blue and red light but not much of the lighter blue, and green and yellow light. It looks bluish green. Chlorophyll and Accessory Pigments Leaves have evolved to produce several other pigments called Give a accessory pigments. brief overview of what Accessory you’ll cover in your presentation. pigments absorb wavelengths of light that chlorophyll cannot absorb effectively, enabling the plant to use more of the sun’s energy. -the reason leaves change colors in autumn. In green leaves, there is so much cholorphyll that is masks other pigments. Discussion The following are the types of accessory pigments: Give a brief overview of what you’ll cover in your presentation. 1. Chlorophyll b 2. Carotenoids 3. Anthocyanins 4. Xanthophylls Chlorophyll b It is structurally only slightly different from chlorophyll Give a brief overview of what you’ll cover in your presentation. a but its absorption spectrum is somewhat different. It absorbs more in the blue and orange-red ranges. It looks yellowish green. Captured energy is handed over to chlorophyll a, which is a smaller but more plentiful molecule in the chloroplast. Carotenoids They absorb light from violet to the greenish-blue Give a brief overview of what you’ll cover in your presentation. range. They appear in various shades of yellow or yellow orange, or red to our eyes. They cluster next to chlorophyll a molecules to efficiently hand off absorbed photons. They are usually found attached to proteins or membranes in the chloroplasts. Anthocyanins They do not participate in photosynthesis and may appear red, Give a brief overview of what you’ll cover in your presentation. purple or violet, or blue. They occur widely among higher plants. They are pigments that generally give color to flowers but also occur in leaves and fruits. In leaves, these pigments often help to protect against excessive sunlight that can damage some leaf tissues. This is one reason why a young, newly developing leaf is often redder than when it reaches its mature size. Xanthophylls They pass along light energy to chlorophyll a Give a brief overview of what you’ll cover in your presentation. and act as antioxidants. The molecular structure gives xanthophylls the ability to accept or donate electrons. Xanthophyll pigments produce the yellow color in fall leaves. NOTE Representation of Give a brief overview of what you’ll cover in your presentation. energy transfer by antenna pigments. DISCUSSION The leaves of plants have mesophyll cells, the Give a brief overview of what you’ll cover in your presentation. photosynthetic cells. These cells possess specialized structures called chloroplasts where photosynthetic pigments are located (Figure 9). Other pigments that are not involved in photosynthesis are stored in the vacuole, a large cellular structure that also serves as storage place of water and nutrients. https://www.sciencefacts.net/wp- content/uploads/2022/09/Mesophyll.jpg Leaf cross section Chloroplasts Vein Mesophyll cell layer Stomata CO Chloroplast Single mesophyll cell Stroma Outer membrane Thylakoid Thylakoid Intermembrane Granum space space Inner membrane  Q2 MODULE 1 DISCUSSION DONE (Prepare for Q2 Module 2)