1st Quarter General Biology Reviewer PDF

Reviewer in General Biology 1 1st Quarter Exam Ribosomes Cell Theory Vesicles – for transport 1. Cell is the basic unit of life. Lysosomes 2. All living organisms are made up...

Reviewer in General Biology 1 1st Quarter Exam Ribosomes Cell Theory Vesicles – for transport 1. Cell is the basic unit of life. Lysosomes 2. All living organisms are made up of cell. Types of Tissues 3. All cells arise from pre-existing cells. Epithelial tissue – commonly seen outside the body as coverings or as linings of organs. Zacharias Janssen, a Dutch spectacle-maker Connective tissue – blood, connective tissue who discovered the first compound microscope proper, cartilage, bone Galileo Galilei, was also able to make his own Muscle tissue - muscle fibers that allow the microscope because of his knowledge about body to move voluntary or involuntary glass and focal lengths. Nervous tissue - are composed of nerve cells Anton van Leeuwenhoek made his own very called neurons and glial cells that function as odd looking version. support cells. Robert Hooke was able to coin the term “cell” Cell Modifications by looking at a piece of cork stripped from the Apical modifications – found on apical surface trunk of the Cork Oak tree under his of the cell microscope. Ex. Cilia, flagella, microvilli, pseudopods, Extra Matthias Schlieden, a German botanist who cellular matrix loves observing his plants under the microscope, noticed that every plant is made up Cell Cycle of cells. On the other hand, zoologist Theodor Interphase  Mitosis  Cytokinesis Schwann also studied different animals using Interphase his microscope and later on concluded that  G1 phase – cell growth animals are made up of cells.  S phase – DNA replication Rudolf Virchow is known as the “Father of  G2 phase – cell growth (cell is matured Modern Pathology”. He published his now and big enough), prepares the cell for M famous aphorism “omnis cellula e cellula” which phase means “every cell stems from another cell.” Checkpoints Continued research and with advancement of  FIRST CHECKPOINT (Restriction point) technologies, additional postulates were added: - G1 Checkpoint 1. All cells contain hereditary -This is where they ensure that the cell information which is passed from cell to size is large enough to divide, and to cell during division. check if the nutrients and proteins 2. All cells are basically the same in reserves are enough for the daughter chemical composition. cells. 3. All energy flow of life occurs within  SECOND CHECKPOINT (G2 Checkpoint) cells. - This event ensures that the DNA have been accurately replicated Prokaryotic cells Eukaryotic cells without mistake or damage. If it Has DNA Has DNA detects a problem, the cell will Has no nucleus Has nucleus either complete the replication or Lack of organelles Complete organelles repair the damaged DNA. Unicellular or single- Multicellular –  METAPHASE CHECKPOINT celled organisms organisms that have - It ensures that the chromosomes many cells are attached to the spindle microtubules. Plant cell Animal cell p53 (Tumor Suppressor Gene) Has cell wall Has no cell wall - If there is a damage in DNA (might Has large vacuole Has many smaller be caused by heat, radiation or vacuoles chemicals), the cell division would Has chloroplast for Has no chloroplast photosynthesis stop and the normal p53 would Chlorophyll – plant trigger enzymes to repair the pigment for damaged DNA. Once the DNA is capturing light repaired, the p53 would allow the Nucleus cell division to continue. However, Mitochondria if the damage is beyond repair, p53 Cell membrane would trigger the destruction of the SER (smooth endoplasmic reticulum) cell (apoptosis). If the p53 failed to RER (rough endoplasmic reticulum)  these functions, there would arise the cancer cells. Kinases and Cyclins - Kinases are enzymes that combine phosphate groups to other molecules like sugars and proteins. - Cyclin serves an activating protein that bind to a kinase to form Cdk complex. - Cylins-dependent Kinases are kinases which either activates or deactivates another protein  through phosphorylating them. It gives the ‘stop’ and ‘go’ signal at the Gap 1 and Gap 2 checkpoints. M phase (Mitosis) – Cell division (cell repair, cell growth)  Produces 2 daughter cells  Daughter cells are genetically identical to the parent cell  PMAT – Prophase, Metaphase, Anaphase, Telophase, Cytokinesis  Cytokinesis – division of cytoplasm   46 chromosomes of parent cell, 46 Disorders chromosomes each for the daughter Cancer – uncontrollable cell division cell Down syndrome (Trisomy 21) – extra chromosome 21 Turner’s syndrome – 45 chromosomes Alzheimer’s disease – dying of neurons resulting to loss of memory Klinefelter Syndrome - It is presented as XXY and usually happens to males. XYY Syndrome - Also happens to male human. Person with this abnormality has no distinct physical features and mostly show behavioral difference (Healthline, 2016). Trisomy X (Triple X Syndrome) - Has 47 chromosomes and this time there are three X  chromosome and no Y chromosome. This Meiosis – cell division for sex cell (gametes) happens in female humans.  4 daughter cells are produced Chromosomal Alterations - In this disorder,  Each daughter cell has 23 chromosomes there is a part of chromosome that is affected.  23N = Haploid gametes DUPLICATION  Daughter cells are genetically different DELETION (Cri du cat syndrome) form parent cell, this is for the genetic TRANSLOCATION diversity of organisms  Crossing over – this is when non sister Applications of Mitosis in different fields chromatids exchange genetic material STEM CELLS. These are cells that are like clay  Synapsis – pairing of homologous that is ready to be molded to get a specific chromosomes shape. Stem cells can become a blood cell, muscle cell, skin cell or any type of cell. AGRICULTURE. Cloning is used. Cloning in biotechnology is the process of creating copies of DNA fragments, cells or organisms. TISSUE CULTURE is also an application of mitosis. Tissue culture can be done in animal or plant cell. It is defined by (Britannica, 2015) as fragments of tissue from an animal or plant are transferred to an artificial environment in which - Phagocytosis: The intake of a large they can continue to survive and function. droplet of extracellular fluid. This occurs in specialized cells. Structure of Plasma membrane - Receptor-assisted endocytosis: The Phospholipids – main fabric of the intake of specific molecules that membrane (hydrophilic head and attach to special proteins in the cell hydrophobic tail) membrane. These proteins are Cholesterol – Dampen effects of uniquely shaped to fit the shape of temperature a specific molecule. Integral proteins – Transport of substance through membrane Peripheral proteins – cell-to-cell recognition Carbohydrate chains – cell recognition Transport Mechanisms Passive transport – doesn’t need energy to transport molecules 1. Simple Diffusion - Passive movement of molecules from a region of high concentration to a region of low concentration. 2. Facilitated Diffusion - Passive movement of a substance into or out of the cell by means of carrier proteins or channel proteins 3. Osmosis - (Diffusion of water)  Isotonic: Water inside the cell equals the water outside the cell and equal amounts of water move in and out of the cell.  Hypotonic: Water outside the cell is greater than that inside the cell, water moves into the cell, may cause cell to burst (lysis)  Hypertonic: Water inside the cell is greater than outside. Water moves out of the cell, may cause the cell to shrink (plasmolysis) 4. Active transport - is the movement of molecules from LOW to HIGH concentration. Energy is required as molecules must be pumped against the concentration gradient. Proteins that work as pumps are called protein pumps. Sodium potassium pump - antiporter transport protein 5. Bulk transport EXOcytosis = how materials EXIT the cell (how the cell uses the bathroom) ENDOcytosis = how materials ENTER the cell (cell eating/engulfing) 3 Types of Endocytosis: - Pinocytosis: The intake of a small droplet of extracellular fluid. This occurs in nearly all cell types.