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TOPIC: Cell Biology 2. Cell is the basic unit of life in all living things 3. All cell comes from pre-existing cell Cell Theory: The Development of the Classical Cell Theory...

TOPIC: Cell Biology 2. Cell is the basic unit of life in all living things 3. All cell comes from pre-existing cell Cell Theory: The Development of the Classical Cell Theory Properties of Life Aristotle 1. Organization (Order) 2. Growth and Development spontaneous generation, “Life can arise from 3. Response to Stimuli non-living matter” 4. Homeostasis Francesco Redi (1626-1697) 5. Energy Processing 6. Reproduce on their own conducted an experiment to disprove the idea of spontaneous generation Cell- basic and fundamental unit of life, it possesses a highly organized structure that enables it to carry out Louis Pasteur its vital functions. Swan-neck Flask Experiment Types of Cells “Life comes only from life” Earn novel prize Prokaryotic- lack a defined nucleus, dispersed genetic material in the cytoplasm The Modern Cell Theory Eukaryotic- have a defined nucleus - Plant- cellulose cell wall; chloroplast and Robert Hooke vacuoles. Created the first microscope - Animal- Rigid cell wall; may have 1665, first person observed the cell under flagella microscope - Protist- they have a cell wall, without He coined the term “cell” differentiated tissues. - Fungal- chitin cell wall; they are Anton Van Leeuwenhoek heterotrophs. Observe tiny living organism and named Structure and Basic Functions animalcules Hook and Leeuwenhoek revolutionized the -These components work together to maintain cellular 19th century homeostasis and perform essential life activities. Robert Brown Cell membrane able to compare different plant specimen under Surrounds the cell and is a selective barrier microscope between the interior and the exterior discovered that each cell has a nucleus Regulates the substance that go in and out of the cell Matthias Schleiden Protein plays a crucial role and facilitating molecular transport and cellular Extensive microscopic observation of the plant communication tissue Plants are made up of cell Cytoplasm Theodor Schwann Gel-like matrix containing water, salts, proteins, and other molecules. Extensive microscopic observation of animal In biochemical reactions, energy production, tissue and substance transport. Animal tissues are made up of all cell Essential for cellular metabolism, it provides Rudolf Virchow structural support to the cell “All cell arises from pre-existing cell” Cell Nucleus Publish essay entitled “cellular Pathology” Houses the DNA, located in the center of Postulate of the cell theory eukaryotic cells Store and safeguard genetic information, 1. All living organism are composed of one or controlling gene expression and DNA more cells replication  Contains the nucleolus, which involved in Energy generation through cellular respiration ribosome synthesis (ATP production) It allows for organization of various stages of Protein Synthesis respiratory chain, making it crucial for cellular -Building and repairing cellular structure, regulating function and survival. biological process, and expressing specific Chloroplasts characteristics of each organism Exclusive to plant cell and photosynthetic Ribosome organism, it carries out photosynthesis, Essential organelles for cellular functioning converting solar energy into chemical energy. and survival During the photosynthesis, they synthesize Synthesize protein using the genetic glucose and other organic compounds using information from messenger RNA (mRNA) carbon dioxide and water, releasing oxygen as that is crucial for cellular structure, function, a by product and regulation Production of oxygen that sustains the plant Located in the cytoplasm and the rough Cellular Digestion endoplasmic reticulum Breaking down molecules and unwanted materials, Endoplasmic reticulum recycling nutrients and cellular maintenance. Interconnected membranes that extend from Lysosomes the nuclear membrane to the cell membrane. It transports, processing, and distribution of Contain enzymes that breakdown molecules protein and lipids within the cell and unwanted cellular materials Two types of ER It helps disposing of water, recycling nutrients, - Rough Endoplasmic Reticulum and defending against pathogenic invasions. (RER)- studded with ribosomes and involve in synthesis and modification Peroxisomes of protein Degrade hydrogen peroxide and toxic - Smooth Endoplasmic Reticulum compound, it protects the cell from oxidative (SER)- specializes in lipid synthesis, damage carbohydrate metabolism, and Play roles in the synthesis and degradation of detoxification. lipids and bile acids, regulating lipid Golgi Apparatus metabolism and overall homeostasis. Processing and packaging of proteins and Support and Movement lipids Maintaining cellular shape, enabling cellular Synthesizes carbohydrates and lipoproteins, movement and division, are essential for its also this is essential for maintaining the cell’s functioning and survival. internal balance and facilitating communication with the outside. Cytoskeleton Series of flatten sacs that called cisternae, it Composed of protein filaments (microtubules, acts as the shipping center of the cell, sorting microfilaments, and intermediate filament) and and packing proteins into vesicle for transport provides support and enables movement in and distribution. eukaryotic cell. Energy Supply It regulates cellular shape and plays a role in division, migration, and communication -To carry out vital functions and necessary metabolic processes essential for the proper functioning of the Flagella and cilia cell and/ or organism. Structures for movement, elongated ad enable locomotion in liquid environment. Cilia are shorter and create coordinated flow on the cell Mitochondria surface Present in eukaryotic animal and plant cells Composed of microtubules in a ‘9+2’ pattern, essential for sperm motility, Storage and Transportation Manage nutrients, eliminate waste, and regulate metabolic processes. Vacuoles Membrane-bound organelles found in plant and some animal cells. They store nutrients, water, ions, and waste materials, regulating turgor pressure and osmotic balance. Involved in the digestion of substances and serve as a defense mechanism against predators by containing toxins Vesicles and Endosomes Membranous vesicles that transport specific materials between organelles and the cell membrane. Vesicles- transport materials from endoplasmic reticulum and the Golgi apparatus to other destination Endosomes: They capture and distribute material for degradation, recycling, or their incorporation into metabolic pathways. Taxonomy Naming and classifying of organisms. It is basically the methodology and principles of systematic classification of the kinds of plants and animals in hierarchies of superior and subordinate group. Nucleoid Lacks membrane-bound organelles Genetic materials are suspended on the cytoplasm Eukaryotes Derive it names from “eu” means true while karyon means “nucleus”. Prokaryotes Eukaryotic Cell Structure Genetic materials of prokaryotes found in a Eukaryotic organism includes protozoans, region called nucleoid. algae, fungi, plants, and animals. Some of Unicellular eukaryotic cells are independent, singled- Lacks membrane-bound organelles celled microorganism, whereas others are part Occurs singles, in pair, chains, cluster, of multicellular organism. aggregates and colonies. Prokaryotic Cell Structure TOPIC: Cell Cycle Cyclins and cyclin dependent kinases (CDKs) are proteins that promote events in the cell Has two main phases, mitotic phase and cycle. They carry positive regulation interphase RB or retinoblastoma protein is one of the During interphase, the cell grows, organelles proteins that is considered a negative regulator are being copied, and the genetic material that stop the cell cycle from moving forward. (DNA) is replicated. It happened in G1 control point where the cell During the mitotic phase, the replicate DNA, is prevented from entering the S phase. This is the cytoplasm, and the organelles in it are until damaged DNA is repaired repeated. Then finally, the cell divides. The new identical daughter cells are formed. The Cell Cycle and Cancer The G1 phase (Gap 1) Cancer is a disease that result when cell division becomes uncontrolled. Mutated cells The cell grows, the organelles are duplicated go unchecked in control point and divide out Cell carries out normal metabolism, produce of control. They usually clumped or grouped RNA, and synthesize proteins together to form tumor that can affect and “Decision making step” where the cell destroy normal cell. decided if it will start a next cycle, rest or permanently exit the cell cycle to become Eukaryotic Chromosomes differentiated cell (GO) Every organism possesses a definite number of The S Phase (Synthesis) chromosomes. For example, each cell in the body of a human being contains 46 The genetic material DNA is replicated or chromosomes (except the human sperm cell copied. Also, the centrosome is duplicated. and egg cell). The cell continues to grow and prepares for The DNA (Deoxyribonucleic Acid) in the mitosis to happen. chromosomes of eukaryotes is associated with Mitotic Phase various protein, including histones that is involved in organizing chromosomes. Phase where the cell divided via cytokinesis to Chromatin produce two daughter cells. Mutation The DNA within the nucleus is inn its loosed form and forms a tangled mass of thin thread, When there are mistakes in the duplication or this happens when a cell is not undergoing distribution of the chromosomes or genes. The division. mutation is the abnormal cell could be passed Before mitosis begins, chromatin become on to every new cell produced. chromosomes that are highly coiled and The cell ha internal control mechanism at three condensed. cell cycle control points so that the abnormal cell could not continue to divide and harm Mitosis other cells. Cell division that happens in somatic or cell Cell Cycle Control Points body cell. This is required for both plant and animal Check point, the eukaryotic cell can stop the during development of a single cell into an cell from moving to the next stage individual. It checks if the cell grows with the right cell The main purpose of this is to produce more size, the chromosomes are replicated ad are cell for growth, repair, and development. exact, and they are accurately separated at mitosis. Regulator Molecules of the Cell Cycle Cause the cell cycle to stop or to continue. Some of these important molecules are cyclin, CDK, and Rb  The nuclear envelope reappears around the daughter chromosomes, which then uncoil into chromatin. The nucleolus reappears in each daughter cell, completing karyokinesis, the division of one nucleus into genetically identical nuclei, followed by cytokinesis. Cytokinesis Division of cytoplasm The two daughter cells received a share of the cytoplasmic organelles that duplicated during interphase. Interphase Meiosis Where cell spends the time on this phase Occurs in a sexually mature organism. The DNA in chromosomes copies itself ready The haploid number of chromosomes reduce to cell division to become haploid gametes. The chromosomes the become thicker and Importance start to coil. Make sure that all organisms produced via Prophase sexual reproduction contain the correct The chromatin fibers have condensed into number of chromosomes- half from each discrete chromosomes. parent. The chromosomes appear as two identical Prophase 1 sister chromatids united along the centromeres. During Prophase 1 of meiosis, chromosomes The nucleus disappears and the nuclear condense and the nucleolus disintegrates, envelope start to disintegrate. while centrioles form spindle fibers. The spindle begins to form at the opposite Homologous chromosomes pair up in a poles and the two centrioles migrate away process called synapsis, resulting in tetrads from one another. composed of four sister chromatids. Crossing over occurs between non-sister Metaphase chromatids, allowing for the exchange of The nuclear membrane disappears completely. genetic material at points called chiasmata. The polar fibers continue to extended from the Metaphase 1 poles to the center of the cell The chromosomes begin to move randomly The paired homologous chromosomes have until it finally attach to polar fibers from both moved toward the metaphase plate or at the of their centromeres. center of cell. Kinetochores, protein complexes outside the Anaphase centromeres are present and attached to the spindle fibers. During anaphase, sister chromatids separate at the centromere, forming two daughter Anaphase 1 chromosomes that move toward opposite spindle poles. By the end of this phase, each During cell division, chromosome pairs pole has an equal and complete set of separate and migrate to opposite ends of the chromosomes. cell. In humans, with 46 chromosomes, 23 will move to each pole, resulting in each new cell Telophase containing half the original number of chromosomes. The spindle fibers vanish, and diploid daughter nuclei begin to form at the cell's poles. Telophase Two new nuclei form around each set of chromosomes, leading to the complete division of the two daughter cells, which each contain an equal number of chromosomes. The cytoplasm splits, resulting in the formation of two haploid daughter cells. Interkinesis Interkinesis is a brief phase between the two Application of Mitosis and Meiosis stages of meiosis, similar to interphase in mitosis, but without DNA replication, as Growth and Development chromosomes are already duplicated. involve an increase in cell number through Prophase 2 mitosis, allowing a single organism to develop into a complex multicellular entity. After the Phase 2 involves the formation of four fertilization of an egg cell by a sperm cell, an haploid sex cells (sperm and egg cells). embryo is formed, which continues to grow During this phase, chromosomes condense, into a fully developed organism via mitosis. the nucleolus disintegrates, and chromatids thicken and shorten. Centrioles move to opposite poles, and spindle fibers organize in preparation for the next phase. Metaphase 2 This occurs to ensure sister chromatids separate in the next stage. The two kinetochores of each centromere bind to the spindle fibers from the opposite poles. The chromosomes move until they are on the Cell Replacement metaphase plate. Cells in the body are continuously lost and Anaphase 2 must be replaced. For instance, red blood cells Sister chromatids separate and move to have a lifespan of about 120 days, while skin opposite ends of the cell as the centromeres cells are replaced approximately every 27 divide. days. Microtubules attached to the kinetochores pull the chromatids toward the poles, transforming them into sister chromosomes. Telophase Four new nuclei develop around each set of chromosomes as the spindle fibers disappear. The nuclear envelope begins to form around the daughter chromosomes, and the cytoplasm divides, resulting in the formation of four haploid, genetically distinct daughter cells. Cell Regeneration Cell regeneration involves the use of mitosis to repair damaged tissues in organisms. For example, starfish can regenerate an entire limb through this process.  Stem Cell Regeneration Stem cells are unique cells capable of self- renewal through mitosis and can differentiate into various specialized cell types. Asexual Reproduction They are classified based on their differentiation potential into four categories: occurs in organisms like hydra, which use totipotent, pluripotent, multipotent, and mitosis to create genetically identical unipotent. offspring. In hydras, a bud forms on the parent's body, remains attached while growing, Totipotent and Pluripotent Stem Cells, Multipotent and eventually separates when mature, Totipotent stem cells, or omnipotent cells, can resulting in a new organism that is identical to differentiate into embryonic tissues and form a the parent. complete organism, with fertilized egg cells as an example. Pluripotent stem cells can self-renew and develop into the three germ layers—ectoderm, endoderm, and mesoderm—giving rise to all tissues and organs Multipotent stem cells can self-renew and differentiate into a limited range of related cell types, such as mesenchymal stem cells, which can develop into bones, cartilage, and components of the circulatory system. In contrast, unipotent stem cells can only differentiate into a single cell type. Application of Mitosis Significance of Meiosis Cloning Enables genetic diversity Repair of genetic defects- Meiosis facilitates Mitosis is applied in cloning, which involves the repair of genetic defects in offspring obtaining genetic material from one organism through recombination. If a parent carries a to create an identical copy. genetic defect in one allele, recombination can Gene cloning, or DNA cloning, produces replace it with a healthy allele from the other copies of specific genes by inserting them into parent, resulting in healthier offspring. a vector. Reproductive cloning creates a complete Disorder and Defects of Mitosis and Meiosis organism, while therapeutic cloning focuses on Cancer producing embryonic stem cells for tissue - uncontrolled cell division, linked to creation or replacement. changes in cell cycle regulators. Tissue Culture - Unlike normal cells, cancer cells can proliferate without external growth is a technique that involves transferring factors and can produce their own. fragments of animal or plant tissue to an - They also have the ability to artificial environment to sustain their metastasize, spreading to other body survival and functions. Controlled conditions parts, and often evade apoptosis, or that ensure optimal growth and programmed cell death. multiplication, including the right supply of - The transformation into cancerous nutrients, pH levels, temperature, and cells occurs after the accumulation of appropriate gaseous and liquid environments. mutations in various genes, enabling In plants, it primarily used for propagation, them to replicate more effectively. disease elimination, and enhancing plant propagation, making it a highly efficient technology for agriculture and industry.  Monosomy chromosomal abnormality characterized by the presence of a single chromosome instead of a homologous pair. In humans, this occurs when a gamete with 22 chromosomes (n-1), instead of 23 chromosomes, fertilizes with a normal gamete (n). Trisomy Change in Chromosomes number abnormality where there are three homologous chromosomes instead of the usual pair. Mutation is a key factor that contributes to It occurs when a gamete 24 chromosomes variation among offspring, particularly (n+1), instead of 23 chromosomes, fertilizes through chromosomal mutations, which with a normal gamete (n). involve changes in chromosome number and structure. When an organism has the correct number of chromosomes, it is referred to as euploidy. Changes in chromosome number can result in conditions such as polyploidy and aneuploidy. Polyploid Polyploid organisms are classified based on the number of chromosomes sets they possess: triploid (3n) for three sets, tetraploid (4n) for four sets, and pentaploid (5n) for five sets. Polyploidy is frequently found in plants, including corn, watermelon, strawberry, and bananas. Aneuploidy refers to an organism having an abnormal number of chromosomes. It has two forms: monosomy, where there is one less chromosome (2n - 1), and trisomy, where there is one extra chromosome (2n + 1). Monosomy and trisomy are caused by nondisjunction during meiosis, which can happen in Meiosis I when homologous chromosomes move to the same daughter cell, or in Meiosis II when sister chromatids do not separate, resulting in both chromosomes being present in one gamete. Turner syndrome (XO) is a chromosomal condition in females characterized by the presence of one normal X chromosome and the absence or alteration of the other sex chromosome. It impacts the individual's development both before and after birth. Klinefelter syndrome is a condition primarily affecting boys, caused by the presence of an extra X chromosome. Individuals with this syndrome have a total of 47 chromosomes, consisting of the usual X and Y chromosomes plus an additional X chromosome (XXY). Poly-X females or superfemales, are individuals with more than two X chromosomes, typically having either XXX or XXXX sex chromosomes. Jacobs syndrome is a condition where males have XYY sex chromosomes. This disorder happens because of the nondisjunction during spermatogenesis. These individuals are sometimes called supermales. TOPIC: Cell Membrane Protein- help together diffusion and cell recognition separation between intracellular and Transport protein (G)- all the way through extracellular environment. the bilayers Ability of a cell to perform a specific chemical Integral protein (F)- also called membrane exchange that is key to life, it is the protein, found on one aspect of membrane. semipermeable membrane that cause this Glucose uses these channel proteins too help potential. move across cell membranes passively Phospholipid Bilayers Channel protein- transport ions and polar molecules, the pores allow substance to pass Phospholipid through without binding to the protein. Main components of the cell membranes. It is Carrier protein- proteins facilitate the barrier to water soluble molecules that line up movement of ions and polar molecules across in a bilayer arrangement. the cell membrane. Can transport substances Takot daw sa tubig(sabi sa notes ko) either along or against the concentration gradient by altering their shape and binding to the substances. The carbohydrate chain (D) on the glycoprotein (C) allows it to act as a receptor molecule. They can bind with certain substances and some act as cell markers for cell-to-cell recognition. Glycolipids- stabilize the cell membrane by making hydrogen bonds with nearby water molecules. They support with cell recognition and triggering immune responses. Transport Mechanism The cell membrane is a lipid bilayer embedded with various proteins that perform essential functions, including regulating the movement of solutes in and out of the cell. Solute transport occurs through four distinct processes: passive diffusion (down a gradient), carrier-mediated Hydrophilic- water loving transport (down a gradient), primary active transport (against a gradient), and Hydrophobic- water hating secondary-active transport (also against a gradient). Additionally, the membrane features channels made of membrane-spanning Cell Membrane Components proteins that facilitate solute diffusion down a gradient. Cholesterol (E)- manage the fluidity, stops the phospholipids to sitting closely to each other reduces the chance of membrane freezing in cold temperatures Passive Trasport Movement of substance through membranes Active Transport without energy Movement of molecules against a It depends on the permeability of the cell concentration gradient (lower concentration to membrane. higher concentration). Where use carrier Three types: diffusion, osmosis, and facilitated proteins that binds specific molecules. This diffusion type of molecular transport needs energy or Diffusion Adenosine Triphosphate (ATP) Net passive movement of particles (atoms, ions or molecules) from area of higher concentration to lower concentration If galing sa labas, higher to lower concentration If galing sa loob, lower to higher concentration. Example, re-absorption of glucose, amino acid, and salt by the proximal convoluted tubule within the nephron is the kidney Osmosis Special example oof diffusion where the water through a partly semipermeable membrane from a more dilute solution to a more Endocytosis and Exocytosis concentrated solution. The transport of materials into and out of cells occurs via membrane-bound sacs that detach from the cell membrane. This process includes endocytosis and exocytosis, both of which involve the formation of vesicles to facilitate the movement of substances across the lipid bilayer. the process by which a cell takes in materials from its environment. The cell membrane creates a pocket around the material, which then pinches off to form a vesicle. These vesicles can merge with lysosomes or other Facilitated diffusion organelles. There are three types of endocytosis: phagocytosis, pinocytosis, and Movement of specific molecules down a receptor-mediated endocytosis. concentration gradient, passing through the membrane via particular carrier protein.  Exocytosis is the process by which waste and other byproducts are expelled from a cell. This occurs when vesicles formed in the Golgi complex fuse with the cell membrane, releasing their contents outside the cell. Cells utilize exocytosis to export proteins packaged by the Golgi complex, particularly in nerve cells and glandular cells. This process allows cells to release signaling proteins and waste products while also permitting the intake of essential molecules like nutrients.