Biology Reviewer GEN-BIO-1

***I. INTRODUCTION*** **Biology** - the science of life \- the study of structures, functions and relationships of living organisms. **CHARACTERISTICS OF LIVING ORGANISMS** **1.** Organization - living things have complex system of substances organized in a special state of chemical activity --...

***I. INTRODUCTION*** **Biology** - the science of life \- the study of structures, functions and relationships of living organisms. **CHARACTERISTICS OF LIVING ORGANISMS** **1.** Organization - living things have complex system of substances organized in a special state of chemical activity -- " the living condition 2.Metabolism -- the totality of the physical and chemical changes taking place in organisms. Classified into 2 groups: anabolism and catabolism 3\. Growth -- when the organism takes in more material from its environment that it gives back and organizes these materials into its own structures, the organism increases it sizes. 4\. Reproduction -- self-controlled duplication of the structural characteristics of living things. 5\. Responsiveness or Irritability -- a living organism is able to react to stimulus. 6\. Adaptation -- the process in which a species slowly or rapidly becomes better suited to survive. 7\. Homeostasis -- maintenance of a nearly constant condition within an organism. 8\. Evolution -- the change occurring over long period of time have enabled the organisms to live in their environment. **LEVELS OF BIOLOGICAL ORGANIZATION** Cell **→** Tissue **→** Organ **→** Organ System **→** Organism **CLASSIFICATION SYSTEMS** There are about 3 million of animals and 350,000 species of plants. There is, thus, a need to classify organisms in a logical and meaningful manner. \- Classification and nomenclature \* Artificial system of classification \- grouping of organisms based on superficial resemblances, does not show the real relationships of organisms \* Natural classification \- based on evolutionary relationships of organisms \- Started by Karl Von Linne or Carolus Linnaeus (father of taxonomy) Nomenclature -- system of naming organisms Binomial Nomenclature -- giving of an organism a scientific name which is composed of two names: genus name and species name. Some Rules in Binomial Nomenclature: 1. An organism is given a scientific name which is in Latin and composed of a genus name and species name. 2. Only the first letter of the genus name is capitalized; the rest of the letters of the genus name and species name are in small case letters. The scientific name is italiziced or underlined. Ex. [Homo] [sapiens] or *Homo sapiens* (scientific name of man) 3. The first scientific name published becomes the valid name and the rest are just synonyms. 4. No scientific names prior to those included in the 10^th^ Volume of Linnaues [Systema] Naturae are recognized. -Homology in structure or appearance Ex. Organisms with jointed appendages are group Together -Homology in the number of chromosomes Ex. Organisms belonging to the same species have the same number of chromosomes -Homology in function Ex. Animals with backbones also have insulin- secreting cells -Homology in chemical composition Ex. Turkeys and pigeons differ by 4 amino acids onlyTurkeys and turtles differ by 8 amino acids **The five-kingdom classification scheme is based on** **the following criteria:** **1.** Types of cells -- organisms may have: Prokaryotic cells -- the genetic material is not enclosed by a nuclear membrane. Eukaryotic cells -- the genetic material is enclosed by a nuclear membrane. 1\. Number of cells -- organisms may be: Unicellular -- composed of one cell Multicellular -- composed of many cells 2\. Modes of nutrition -- organisms may be: 1. Kingdom Monera -- prokaryotic organisms 2. Kingdom Protista -- eukaryotic organisms 3. Kingdom Fungi -- eukaryotic organisms 4. Kingdom Plantae -- eukaryotic organisms - multicellular - photosynthetic - primarily non-motile a. b. c. 5\. Kingdom Animalia -- eukaryotic organisms, multicellular, ingestive type of nutrition, primarily motile A. Phylum Porifera -- sponges B. Phylum Coelenterata -- corals, jellyfish, sea anemones C. Phylum Platyhelminthes -- flatworms D. Phylum Nematoda -- round worms E. Phylum Annelida -- segmented worms F. Phylum Mollusca -- shells, snails, clams, squids, octopus G. Phylum Arthropoda -- crustaceans (crabs, shrimps, lobsters), insects, centipedes, millepeds, spiders, scorpions H. Phylum Echinodermata -- sea urchins, sea stars, sea cucumbers, brittle stars I. Phylum Chordata -- fishes (bony and cartilaginous), amphibian, (frogs and toads), reptiles, birds, mammals **Tools Used in the Development of Biology** The subject of this lesson is the MICROSCOPE. The microscope is a tool used to study objects too small to be seen with the unaided eye. You will be using the microscope to discover a whole world of life too small to be seen with the eye alone. The study of the diversity of life will begin with microscopic organisms and progress to the largest organism. The microscope enlarges the image of a small object. In your biology class, you will be using the compound microscope. It consists of two lenses, each fitted into the end of a tube within a tube. How to Prepare the Microscope The word microscope comes from the Greek word micro meaning "small" and scope it means "to see or view." The purpose of a microscope is to magnify small objects so that they can be seen. The microscope that you will be using is both a light and a compound microscope. The light for your microscope will come from sunlight. The word compound refers to a microscope with two lenses or a set of lenses. There are two sets of lenses in a microscope, one at each end of the body tube. The two sets of lenses are called the EYEPIECE and the OBJECTIVE. **How to Focus the Microscope** The purpose of adjusting or focusing the microscope is to produce a magnified image that is sharp. That is where the problem begins. Do not be surprised if you do not get sharp images at once. The scientific word for focusing to get a sharp image is RESOLUTION. MAGNIFICATION is the enlarging of an image. Resolution and magnification are two different things. The problem is that you cannot get good resolution and good magnification at the same time. A microscope may have to be continually adjusted to get a sharp picture. This is especially true when you are viewing living things. They swim up and down in a drop of water. As an organism moves in a drop of water, it will go out of focus. Turn the adjustment knob to bring the image back into focus. The Limitations of a Microscope 1\. Resolution limits magnification. 2\. Continual focusing is necessary if the object moves. 3\. Image will be upside-down and reversed. Microscope Parts and Their Functions 1\. Arm. Supports the body tube. 2\. Eyepiece. Contains the magnifying lens you look through. 3\. Body tube. Maintains the proper distance between the eyepiece and objective lens. 4\. Nosepiece. Holds objective lens. 5\. Objective lens. A lens which usually provide a 10x or a 20x magnification. 6\. Stage clips. Hold the slide in place. 7\. Stage. Supports the slide being viewed. 8\. Diaphragm. Regulates the amount of light let into the body tube. 9\. Mirror. Reflects the light upward through the diaphragm, the specimen, and the lenses. 10\. Base. Supports the microscope. 11\. Adjustment knob. Moves the body tube up and down for focusing. Other Tools of the Biologist In the 1930s, scientists developed the first electron microscope. This type of microscope used beams of electrons, instead of light, to make an image. Today, there are two types of electron microscopes, the transmission electron microscope (TEM) and the scanning electron microscope (SEM). In the TEM, electrons actually pass through the object being viewed. The biologist sees a thin, flat view of the structures of a specimen. The SEM gives the biologist a surface view of a specimen by coating the specimen with metal, causing the electrons to bounce off the surface. Special detectors pick up the electrons and convert them on a television screen. Computers have also increased our knowledge by storing and processing great quantities of data. **CELLULAR BASIS OF LIFE** Robert Hooke (1665), British scientist -- observed mass of tiny cavities from thin slices of cork with his self-made microscope, he named these structures "cells" since these structures reminded him of the small rooms in a monastery. Anton Van Leeeuwenhoek (1674), Dutch scientist -- made pioneering discoveries concerning protozoa, red blood cells, capillary systems, and the life cycles of insects, he also perfected the construction of the compound microscope. Robert Brown (1831), British botanist -- observed plant cells with a distinct central part (nucleus); described the streaming movement of the cytoplasm (Brownian movement). Matthias Schleiden (1838), German botanist -- concluded that plants are composed of cells. Theodore Schwann (1839), German zoologist -- concluded that animals are composed of cells. Rudolf Virchow (1858), German pathologist -- concluded that all cells must come only from pre-existing cells. James Watson, American biochemist and Francis Crick, British biophysicist (1953) -- discovered the structure of DNA that ushered in the era of molecular biology. Cell -- minute mass of protoplasm which is the unit of structure and function of living things. Cell Structure and Functions 1\. **Outer Boundaries of cells** **Cellular Respiration** - **Cellular Respiration:** The process of converting food energy into ATP energy. - **Chemical Equation:** C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + 36 ATP - **Why Plants Need Chloroplasts and Mitochondria:** - **Chloroplasts:** Use energy from the sun to make glucose. - **Mitochondria:** Convert glucose to ATP, the energy currency of the cell. - **What is ATP?** - Adenosine Triphosphate (ATP) is the energy currency of the cell. - It consists of a 5-carbon sugar (ribose), a nitrogenous base (adenine), and 3 phosphate groups. - The chemical bonds linking the phosphate groups are high-energy bonds. - When a phosphate group is removed, energy is released. - **How is ATP Used?** - ATP provides energy for: - Synthesizing molecules for growth and reproduction. - Transport work (active transport, endocytosis, and exocytosis). - Mechanical work (muscle contraction, cilia and flagella movement, organelle movement). - **Stages of Cellular Respiration:** - **Glycolysis:** Glucose is broken down into pyruvate, producing some ATP. - **Aerobic Respiration:** Occurs in the presence of oxygen. - **Krebs Cycle:** Produces energy-storing molecules. - **Electron Transport Chain:** Produces large amounts of ATP. - **Anaerobic Respiration:** Occurs in the absence of oxygen. - **Fermentation:** Regenerates NAD+ needed for glycolysis to continue. - **Lactic Acid Fermentation:** Pyruvate is converted to lactate. - **Cellular Respiration is a Metabolic Process:** - It releases energy from food to make ATP. - The ATP provides cells with the energy they need for life. **Aerobic Respiration:** - **Requires Oxygen:** Aerobic respiration needs oxygen to proceed. - **More Efficient:** It produces significantly more ATP (around 36-38 molecules) per glucose molecule than anaerobic respiration. - **Stages:** - **Glycolysis:** Glucose is broken down into pyruvate, producing a small amount of ATP (2 molecules). This stage occurs in the cytoplasm. - **Krebs Cycle (Citric Acid Cycle):** Pyruvate is further broken down, producing more ATP (2 molecules), electron carriers (NADH and FADH2), and carbon dioxide. This stage occurs inside the mitochondria. - **Electron Transport Chain:** The electron carriers deliver electrons to a chain of proteins embedded in the mitochondrial membrane. This process drives the production of the majority of ATP (around 32 molecules). **Anaerobic Respiration:** - **Does Not Require Oxygen:** Anaerobic respiration can proceed without oxygen. - **Less Efficient:** It produces much less ATP (only 2 molecules) per glucose molecule than aerobic respiration. - **Stages:** - **Glycolysis:** It\'s the same as in aerobic respiration. - **Fermentation:** Since oxygen is not available, pyruvate is converted to other products, regenerating NAD+ which is required for glycolysis to continue. There are two main types of fermentation: - **Lactic Acid Fermentation:** Pyruvate is converted to lactate (lactic acid). This occurs in muscle cells during intense exercise when oxygen supply is limited. - **Alcohol Fermentation:** Pyruvate is converted to ethanol (alcohol) and carbon dioxide. This is used by yeast and some bacteria. **Here\'s a table summarizing the key differences:** **Feature** **Aerobic Respiration** **Anaerobic Respiration** -------------------- ------------------------- --------------------------- Oxygen Requirement Requires Oxygen Does not require oxygen ATP Production High (36-38 ATP) Low (2 ATP) Products CO2, H2O, ATP Lactate, ethanol, CO2 Location Mitochondria Cytoplasm **In summary:** - Aerobic respiration is the more efficient way to produce ATP, but it requires oxygen. - Anaerobic respiration can occur in the absence of oxygen, but it produces much less ATP. **Photosynthesis and cellular respiration, two fundamental processes in biology.** **1. Cells and Their Structures:** - **Cells:** The basic unit of life, all organisms are made of cells. - **Prokaryotic Cells:** Lack a nucleus, simpler in structure. - **Eukaryotic Cells:** Have a nucleus, more complex, contain organelles like mitochondria and chloroplasts. - **Key Organelles:** - **Nucleus:** Controls cell functions, contains genetic information in chromosomes. - **Cell Membrane:** Controls what enters and exits the cell. - **Ribosomes:** Produce proteins. - **Mitochondria:** Release energy from glucose. - **Chloroplasts (plants):** Contain chlorophyll, convert sunlight into food for the plant. - **Cell Wall (plants):** Protective layer surrounding the cell membrane. **2. Photosynthesis:** - **Energy for Life:** All living things need energy to function. - **Process:** Plants and some organisms use sunlight to convert carbon dioxide and water into oxygen and sugars (glucose). - **Steps:** i. ii. iii. - **Equation:** 6CO2 + 6H2O + sunlight energy → C6H12O6 + 6O2 - **Purpose:** i. Provides energy for almost all living things, directly or indirectly. ii. Produces most of the oxygen in Earth\'s atmosphere. **3. Cellular Respiration:** - **Energy Release:** Cells break down glucose to release stored energy. - **Process:** Glucose is broken down, releasing energy in the form of ATP. - **Steps:** i. ii. iii. - **Equation:** C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP) - **Connection to Breathing:** We breathe in oxygen for cellular respiration and breathe out carbon dioxide and water as byproducts. **4. Photosynthesis vs. Cellular Respiration:** - **Opposite Processes:** Photosynthesis uses sunlight to create glucose and oxygen, while cellular respiration uses glucose and oxygen to release energy. - **Energy Cycle:** Photosynthesis captures energy from sunlight, and cellular respiration releases that energy for life processes. **Key Points:** - Photosynthesis and cellular respiration are essential for life on Earth. - Photosynthesis provides the food and oxygen that most organisms need. - Cellular respiration releases the energy stored in food to power life processes. - These processes are interconnected and form a fundamental cycle of energy flow in nature. **Plant Parts and Their Functions: A Summary** This webpage from PMF IAS provides a comprehensive overview of the different parts of a plant and their respective functions. It covers the structural organization of plants, focusing on the root, stem, leaf, flower, fruit, and seed. **1. The Root:** - **Functions:** - **Absorption:** Absorbs water and minerals from the soil. - **Anchorage:** Provides stability and support to the plant. - **Storage:** Stores reserve food material. - **Synthesis:** Produces plant growth regulators. - **Types:** - **Taproot system:** A single, main root with lateral branches (e.g., mustard plant). - **Fibrous root system:** A network of thin roots arising from the base of the stem (e.g., wheat plant). - **Adventitious roots:** Roots arising from parts of the plant other than the radicle (e.g., grass, banyan tree). - **Modifications:** - **Root cap:** Protects the tender root apex. - **Swollen roots:** Store food (e.g., carrots, turnips, sweet potatoes). - **Prop roots:** Support large trees (e.g., banyan tree). - **Stilt roots:** Support stems (e.g., maize, sugarcane). - **Pneumatophores:** Help obtain oxygen for respiration in swampy areas (e.g., Rhizophora). **2. The Stem:** - **Functions:** - **Support:** Holds the plant upright. - **Transport:** Carries water and nutrients from the roots to the leaves. - **Storage:** Stores food. - **Vegetative propagation:** Can produce new plants. - **Types:** - **Woody stems:** Hard and strong (e.g., trees, shrubs). - **Herbaceous stems:** Soft and flexible (e.g., grass, flowers). - **Modifications:** - **Underground stems:** Store food (e.g., potato, ginger, turmeric). - **Stem tendrils:** Help plants climb (e.g., gourds, grapevines). - **Thorns:** Protect the plant from herbivores (e.g., citrus, Bougainvillea). - **Flattened or fleshy stems:** Carry out photosynthesis in arid regions (e.g., Opuntia, Euphorbia). **3. The Leaf:** - **Functions:** - **Photosynthesis:** Produces food for the plant. - **Gas exchange:** Takes in carbon dioxide and releases oxygen. - **Transpiration:** Releases excess water. - **Structure:** - **Leaf base:** Attaches the leaf to the stem. - **Petiole:** Stalk that supports the leaf blade. - **Lamina:** The flat, expanded part of the leaf where photosynthesis occurs. - **Veins:** Provide rigidity and transport water, minerals, and food. - **Venation:** - **Reticulate venation:** Veinlets form a network (dicotyledonous plants). - **Parallel venation:** Veins run parallel to each other (monocotyledonous plants). - **Modifications:** - **Tendrils:** Help plants climb (e.g., peas). - **Spines:** Protect the plant (e.g., cacti). - **Fleshy leaves:** Store food (e.g., onion, garlic). - **Insectivorous leaves:** Trap and digest insects (e.g., pitcher plant, Venus flytrap). **4. Transpiration:** - **Process:** The evaporation of water from the leaves through stomata. - **Functions:** - **Creates suction pull:** Draws water up from the roots. - **Cools the plant:** Releases excess heat. - **Factors affecting transpiration:** Wind, light, temperature, humidity. **5. Respiration in Plants:** - **Process:** Plants take in oxygen and release carbon dioxide, just like animals. - **Occurs:** In all parts of the plant, including the roots. - **Difference from photosynthesis:** Photosynthesis occurs only during the day, while respiration occurs both day and night. **6. The Flower:** - **Function:** The reproductive unit of the flowering plant. - **Types:** - **Bisexual:** Contains both stamens (male) and carpels (female). - **Unisexual:** Contains either stamens or carpels. - **Parts:** - **Sepals:** Protect the flower bud. - **Petals:** Attract pollinators. - **Stamens:** Male reproductive parts (produce pollen). - **Pistil:** Female reproductive parts (contain the ovary and ovules). - **Aestivation:** The arrangement of sepals or petals in the flower bud. **7. Androecium:** - **Male reproductive part:** Made up of stamens. - **Structure:** - **Filament:** Stalk that supports the anther. - **Anther:** Contains pollen sacs where pollen grains are produced. - **Staminode:** A sterile stamen. **8. Gynoecium:** - **Female reproductive part:** Made up of one or more carpels. - **Structure:** - **Stigma:** The receptive surface for pollen. - **Style:** Connects the stigma to the ovary. - **Ovary:** Contains ovules. - **Placentation:** The arrangement of ovules within the ovary. **9. The Fruit:** - **Function:** Protects and disperses seeds. - **Formation:** Develops from the ovary after fertilization. - **Types:** Many variations in shape, size, and color. - **Parthenocarpic fruit:** A fruit formed without fertilization. **10. The Seed:** - **Function:** Contains the embryo of a new plant and a food source for its initial growth. - **Formation:** Develops from the ovule after fertilization. - **Germination:** The process of a seed sprouting and developing into a new plant. **11. Transport of Water and Minerals:** - **Absorption:** Roots absorb water and minerals from the soil. - **Transport:** Water and minerals are transported through the xylem, a vascular tissue that forms a continuous network from the roots to the leaves. - **Food transport:** Food produced in the leaves is transported through the phloem, another vascular tissue. **Key Points:** - Each part of a plant has a specific function that contributes to its survival and growth. - Plants exhibit a wide range of adaptations and modifications to thrive in different environments. - Understanding the structure and function of plant parts is crucial for studying botany and appreciating the complexity of plant life. Photosynthesis is a complex process that occurs in the leaves of plants, allowing them to convert light energy into chemical energy in the form of glucose. This process is vital for the plant\'s survival and growth, as well as for the entire ecosystem, as it produces oxygen and the food source for many organisms. Here\'s a detailed breakdown of photosynthesis in the leaf: **1. The Structure of a Leaf:** - **Chloroplasts:** These organelles are the sites of photosynthesis. They contain chlorophyll, a green pigment that absorbs light energy. - **Stomata:** Tiny pores on the underside of the leaf that allow for gas exchange, letting carbon dioxide in and oxygen out. - **Mesophyll Cells:** The cells in the middle layer of the leaf tissue, where chloroplasts are concentrated, are the primary sites of photosynthesis. - **Xylem and Phloem:** These vascular tissues transport water and nutrients from the roots to the leaves and sugars produced in the leaves to other parts of the plant. **2. The Light-Dependent Reactions:** - **Location:** Thylakoid membranes within the chloroplasts. - **Process:** Light energy is captured by chlorophyll and used to split water molecules. This process releases oxygen as a byproduct and generates ATP (energy-carrying molecule) and NADPH (electron carrier). - **Key Steps:** - **Photoexcitation:** Light energy excites electrons in chlorophyll molecules. - **Electron Transport Chain:** Excited electrons move through a series of protein complexes, releasing energy to pump protons across the thylakoid membrane. - **ATP Synthesis:** The proton gradient drives ATP production through chemiosmosis. - **NADPH Production:** Electrons are used to reduce NADP+ to NADPH, which is a reducing agent. **3. The Light-Independent Reactions (Calvin Cycle):** - **Location:** Stroma of the chloroplasts. - **Process:** Carbon dioxide from the atmosphere is incorporated into organic molecules, using the energy from ATP and the reducing power from NADPH. This results in the production of glucose. - **Key Steps:** - **Carbon Fixation:** Carbon dioxide is attached to a five-carbon sugar (RuBP) to form a six-carbon molecule, which is quickly split into two three-carbon molecules. - **Reduction:** ATP and NADPH are used to convert the three-carbon molecules into a sugar called glyceraldehyde-3-phosphate (G3P). - **Regeneration:** Some G3P molecules are used to regenerate RuBP, allowing the cycle to continue. **4. Overall Equation for Photosynthesis:** 6CO2 + 6H2O + light energy → C6H12O6 + 6O2 - **Carbon Dioxide (CO2):** Enters the leaf through stomata. - **Water (H2O):** Absorbed by the roots and transported to the leaves. - **Light Energy:** Captured by chlorophyll. - **Glucose (C6H12O6):** A simple sugar produced as the plant\'s food source. - **Oxygen (O2):** Released as a byproduct. **Factors Affecting Photosynthesis:** - **Light Intensity:** Higher light intensity generally leads to a higher rate of photosynthesis, up to a point. - **Carbon Dioxide Concentration:** Increasing CO2 levels can boost photosynthesis, but only up to a certain point. - **Temperature:** Photosynthesis has an optimal temperature range, with rates decreasing at very low or high temperatures. - **Water Availability:** Water is essential for photosynthesis; lack of water can reduce the rate of photosynthesis. **In summary:** Photosynthesis is a complex process that involves two stages: the light-dependent reactions and the light-independent reactions (Calvin cycle). These reactions occur in the chloroplasts of leaves and utilize light energy, water, and carbon dioxide to produce glucose and oxygen. This process is essential for plant growth and survival, and it plays a critical role in maintaining the balance of oxygen and carbon dioxide in the Earth\'s atmosphere. Reproduction in Plants: A Detailed Summary ------------------------------------------ This webpage from [ScienceFacts.net](https://sciencefacts.net/) provides a comprehensive overview of plant reproduction, covering both sexual and asexual methods. It delves into the processes, structures, and variations involved in plant propagation. **1. Introduction:** - Reproduction is the biological process of producing offspring of the same type and species. - Plants, like all living organisms, need to reproduce to continue their lineage and pass on their genetic material. **2. Sexual Reproduction:** - **Definition:** Involves the combination of genetic material from two parents (male and female gametes) through fertilization. - **Benefits:** Provides genetic variation, leading to greater adaptability and survival. - **Dominant Stage:** The sporophyte stage dominates the life cycle of flowering plants (angiosperms) and gymnosperms. **2.1. Reproduction in Flowering Plants (Angiosperms):** - **Reproductive Organ:** The flower is the reproductive organ in angiosperms. - **Parts of a Flower:** - **Sepals:** Protect the flower bud. - **Petals:** Attract pollinators. - **Stamen:** Male reproductive organ (consists of anther and filament). - **Carpel:** Female reproductive organ (consists of stigma, style, and ovary). - **Process of Reproduction:** - **Pollination:** Transfer of pollen from the anther to the stigma. - **Self-pollination:** Pollen from the same flower or another flower on the same plant. - **Cross-pollination:** Pollen from a different plant. - **Fertilization:** Fusion of male and female gametes. - **Double Fertilization:** Unique to angiosperms, where one sperm fertilizes the egg cell to form a zygote, and the other sperm fuses with the polar nuclei to form the endosperm (nutritive tissue for the embryo). - **Stages of the Reproductive Cycle:** - **Alternation of Generations:** Plants alternate between a haploid gametophyte stage (producing gametes) and a diploid sporophyte stage (producing spores). **2.2. Reproduction in Non-Flowering Plants (Gymnosperms):** - **Characteristics:** Gymnosperms have \"naked\" seeds (not enclosed in a fruit) and do not undergo double fertilization. - **Life Cycle:** Sporophyte-dominated, with the gametophyte dependent on the sporophyte. **3. Asexual Reproduction:** - **Definition:** Involves a single parent, producing genetically identical offspring (clones). - **Advantages:** Faster maturation, sturdier offspring. - **Disadvantages:** Lack of genetic diversity, making them more vulnerable to diseases and environmental changes. **3.1. Types of Asexual Reproduction:** - **Vegetative Propagation:** New plants arise from parts of the parent plant (e.g., bulbs, tubers, stolons, rhizomes). - **Fragmentation:** New plants develop from broken pieces of the parent plant (e.g., liverworts, mosses). **Key Points:** - Plant reproduction can be sexual or asexual, each with its own advantages and disadvantages. - Sexual reproduction provides genetic diversity, while asexual reproduction produces genetically identical offspring. - The flower is the reproductive organ in angiosperms, while gymnosperms have \"naked\" seeds. - The process of reproduction in flowering plants involves pollination and fertilization, culminating in double fertilization. - Asexual reproduction occurs through vegetative propagation and fragmentation. **Additional Information:** - The webpage also includes FAQs and references for further exploration of plant reproduction. https://www.sciencefacts.net/wp-content/uploads/2019/12/Parts-of-a-Flower-Diagram.jpg