Biology Module 1 Lesson 1: Cell Structure and Modifications PDF

BIOLOGY 11-2 ROGER (2022-2023) – FIRST SEM MODULE 1 Lesson 1: Cell Structure and Modification 08/22/22...

BIOLOGY 11-2 ROGER (2022-2023) – FIRST SEM MODULE 1 Lesson 1: Cell Structure and Modification 08/22/22 OUTLINE Figure 2. Eukaryotic Animal Cell I. Cell Theory V. Cell Modifications II. Type of Cells VI. Review Questions III. Plant vs. Animal Cells IV. Organelles A. Components of Cytoskeleton I. CELL THEORY 1. The cell is the smallest living unit in all organisms. (Schwann. 1838) 2. All living things are made of cells. (Schleiden & Schwann. 1839) 3. All cells come from pre-existing cells. (Rudolf Virchow. 1858) II. TYPES OF CELL Prokaryotes ○ Simple: Unicellular. ○ Example: Bacteria and Archaea. ○ By far the most abundant and diverse form of life inhabiting planet Earth. Eukaryotes ○ Complex: Multicellular III. PLANTS VS. ANIMAL CELLS ○ Example: Protists, Plants, Animals, and Fungi. Table 2. Key Difference between Plants and Animal Cells Note that Kingdom Protista is the most Plant Animal diverse eukaryotic kingdom since it Bigger in size. Nucleus is centralized. contains both unicelled and multicelled Both chloroplast and Cell wall is absent. organisms. mitochondria. Only has mitochondria. Basic Feature of All Cells Big vacuole. Centrosomes, centrioles, ○ Plasma membrane Regular shape. and basal bodies are ○ Semifluid substance: Cytosol Has plastids. present. ○ Chromosomes (Gene Carrier) ○ Ribosomes (Protein Factory) Figure 3. Plant vs. Animal Cell Table 1. Key Difference of Prokaryotes and. Eukaryotes Prokaryotes Eukaryotes No nucleus Membrane-bound DNA in an unbound organelles (complex). region called the DNA in a nucleus that is nucleoid. bounded by a double No membrane-bound membrane. organelles. Cytoplasm in the region The plasma membrane between the plasma bounds the cytoplasm. membrane and nucleus Generally larger than prokaryotes. Figure 1. Prokaryotic Cell IV. ORGANELLES - Specialized structures that perform various jobs inside cells. The term literally means “little organs.” Nucleus ○ Contains most of the cell’s genes and is usually the most conspicuous organelle. ○ The nuclear envelope encloses the nucleus, separating it from the cytoplasm, it’s a double membrane; each membrane consists of a lipid bilayer. 1  ○ Nucleolus: Where ribosomes are formed and RNA ○ Plasmodesmata: openings or channels that synthesized. connect two plant cells. ○ Nucleoid: Where genetic material is found in ○ Middle Lamela: connects/glues together the prokaryotic cells. primary cell walls of two adjoining plant cells. Ribosomes (Protein Factory) Perixosomes – OXIDATIVE REACTIONS ○ Ribosomes are complexes made of ribosomal RNA ○ Metabolic compartments that have enzymes that and protein. transfer hydrogen from various substrates to oxygen ○ It carries out protein synthesis in two locations: producing hydrogen peroxide, and in the liver it ○ In the cytosol (free ribosomes) detoxifies alcohol. ○ On the outside of the endoplasmic reticulum or the nuclear envelope (bound ribosomes). Mitochondria ○ Performs aerobic respiration where energy (ATP) is Cytoplasm obtained from food consumed and made available ○ Semi-fluid liquid that fills the cell and holds the for the use of the cell. Kreb's Cycle and Electron components of a cell; contains all the chemicals the Transport Chain occur here! cell needs to do its living activities. Glycolysis occurs here! Figure 4. Mitochondria ○ Cytosol: The part of the cytoplasm not taken up by organelles and is composed of carbohydrates, proteins, lipids, and molecules such as carbon, hydrogen, and oxygen. Cell Membrane ○ Has a structure known as the fluid mosaic model. The phospholipid bilayer is composed of a phosphate group head (hydrophilic) and two fatty acid tails (hydrophobic). It controls its own biochemistry by only letting certain substances through it. Endoplasmic Reticulum (Manufacturer and Shipper) ○ Help with the production and storage of proteins and where most membranes of the organelles come from. Table 3. Types of Endoplasmic Reticulum Rough Smooth Chloroplast Covered in ribosomes Synthesizes lipids, ○ Site of photosynthesis wherein solar energy is (translates RNA into carbohydrates, and converted to chemical energy. protein) steroid hormones. (testes ○ Belongs to a family of plant structures called plastids Secretes glycoproteins & ovaries) and contains a green pigment called chlorophyll. Distributes/transports Detoxifies drugs and ○ Stroma: fluid surrounding grana. Site for dark vesicles poisons (liver). reactions or the Calvin-Benson cycle. Membrane factory of the Stores calcium ions. Has ○ Thylakoid: sites for light-dependent reaction. cell. a huge role in metabolic processes. Figure 5. Chloroplast. Golgi Apparatus ○ Modifies product of the ER and manufactures certain macromolecules. ○ Sorts and packages materials into transport vesicles. ○ Cis face receiving end because it's near ER while the trans face is shipping. Lysosomes ○ Has hydrolytic enzymes that digest and break down biomolecules. It also works as the recycling facility of the cell. It works best in an acidic environment and it's MADE BY ER AND GOLGI. ○ Autophagy: the gradual turnover of the cell's own components that removes unnecessary or dysfunctional components through a lysosome dependent regulated mechanism. ○ Phagocytosis: cell engulfing another cell, the lysosome then fuses with the food vacuole and digests the molecule Cell Wall ○ Supports and protects the cell and helps resist external pressure; made of cellulose. Cellulose can't be digested by humans. It’s either made of cellulose in plants or chitin in fungi. Peptidoglycan in bacteria. 2  A. CYTOSKELETON 6. Amoebae move by crawling over a surface (cell crawling), - Network of fibers that supports cells to maintain their shape which involves? and internal organization; made up of microtubules, - Growth of actin filaments to form bulges in the microfilaments, and intermediate filaments in eukaryotic cells. plasma membrane kasi actin filaments are also microfilaments that are used in pseudopods. Microtubules ○ Thickest, hollow tube, made up of tubulin, maintains 7. What are motor proteins? shape by compression, and cell motility. - The driving force behind muscle contraction and is ORGANELLE MOVEMENTS. responsible for the active transport of most proteins and vesicles in the cytoplasm, and they move along Microfilaments cytoskeletal filaments ○ Maintains/changes shape by tension-bearing, intertwined actin, for muscle contraction and cell VII. REFERENCES division. Movement of amoeba (pseudopodia). MOVEMENT AS A WHOLE CELL. A. QA MOCK QUIZ Intermediate Filaments https://quizizz.com/join/quiz/633066ff40fa37001e5996f2/start? ○ Coiled fibrous proteins such as keratin. formation of studentShare=true the nuclear lamina. (found in only some animal cells.) fixing formation because it's sturdy. Also maintains shape by tension-bearing. V. CELL MODIFICATIONS Microvilli ○ Brush/striated border on the surface of the cell and has finger-like cytoplasmic extensions of the apical surface which increase surface area for absorption. More surface area = more absorption. Cilia (Alternating strokes) ○ Short hair-like structures that function in movements of materials. On the cell surface and can be found on the lining of the trachea and fallopian tube. Flagella (Tail-like) ○ Whip-like structure that allows the movement of cells (motility). Made up of microtubules (tubulin). Function as a sensory organelle that can detect changes in temperature and pH. VI. REVIEW QUESTIONS 1. In which kinds of human cells would you expect to find the most mitochondria? Lysosomes? Ribosomes? - Mitochondria: heart muscle cells or muscle cells in general. Lysosomes: disease-fighting cells like the white blood cells. Ribosomes: muscle cells and liver to help in metabolic processes. 2. How do prokaryotic cells reproduce? - By a cell division process called binary fission. 3. Vesicles from the Golgi body that will become lysosomes contain enzymes for? - Breaking down cellular debris 4. In which cell would you most likely find microtubules? - In rapidly dividing tumor cells kasi microtubules are the ones responsible for cell division (specifically sa metaphase ng mitosis: centrosomes n centrioles.) 5. Vinblastine, a drug that inhibits microtubule polymerization is used to treat some forms of cancer. Cancer cells that are given Vinblastine would be unable to? - separate chromosomes during cell division. When Vinblastine is present in the dividing cell, the microtubule subunits in the cell cannot polymerize to form mitotic spindles. Hence, the chromosomes remain undistributed, and the cell division is arrested between prophase and metaphase stages. 3