* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Cells - Building Directory
Survey
Document related concepts
Tissue engineering wikipedia , lookup
Signal transduction wikipedia , lookup
Extracellular matrix wikipedia , lookup
Cell growth wikipedia , lookup
Cell nucleus wikipedia , lookup
Cellular differentiation wikipedia , lookup
Cell culture wikipedia , lookup
Cell encapsulation wikipedia , lookup
Cell membrane wikipedia , lookup
Cytokinesis wikipedia , lookup
Organ-on-a-chip wikipedia , lookup
Transcript
Cells Holt Biology Chapter 3 SOL BIO.2 The student will investigate and understand the history of biological concepts. Key concepts include • evidence supporting the cell theory; • scientific explanations of the development of organisms through time (biological evolution); • evidence supporting the germ theory of infectious disease; • development of the structural model of DNA; and • the collaborative efforts of scientists, past and present. SOL BIO.4 The student will investigate and understand relationships between cell structure and function. Key concepts include • characteristics of prokaryotic and eukaryotic cells; • exploring the diversity and variation of eukaryotes; • similarities between the activities of a single cell and a whole organism; and • the cell membrane model (diffusion, osmosis, and active transport). Thoughts to Ponder: • 1.Are cells alive? Why do you think this? • 2.Where are cells located in your body? • 3.Where do the cells in your body get energy? • 4.How do your cells know what to do? What directs their functioning? Objectives • • • • Explain and apply cell theory. Distiguish prokaryotic and eukaryotic cells Distinguish plant and animal cells Describe the appearance and function of the major components of a cell, including: cell membrane, cytoplasm, and the following membrane-bound organelles: nucleus, rough and smooth endoplasmic reticulum, mitochondria, chloroplast, and vacuole. • Describe the appearance and function of some subcellular structures, including ribosomes. Cell Theory • 1665-English Scientist: Robert Hooke • Crude microscope to notice cork made of tiny “boxes” he called cells • 1675-Dutch Scientist: Anton van Leeuwenhoek • Microscope to view pond water—saw “animacules” or tiny animals-plankton Cell Theory (based on these three scientists) • 1838-German Botanist: Mattias Schleiden • Cells make up all parts of a plant • 1839-German Zoologist: Theodor Schwann • Cells make up all parts of animals • 1858-German Physician: Rudolph Virchow • Cells come only from other cells Cell Theory • All living things are made of one or more cells. • All cells arise from pre-existing cells. • Cells are the basic units of structure and function in living organisms Cells: Overview • Most cells are very, very small, so tiny that they can only be seen with the aid of a microscope. • Your body is composed of billions of cells! Within your body, cells have different functions. We have blood cells, skin cells, brain cells...the list goes on. • Despite their differences, cells in living organisms for the most part have similar structures and functions. • Question 1.Have you ever seen a cell? When? What do you remember about it? Stop • Review volume section of metric worksheet Surface Area to Volume Animal and Plant Cell parts • cell membrane which serves as a boundary between the cell and the outside environment • cytoplasm containing organelles • nucleus containing hereditary material (DNA) • mitochondrion (plural, mitochondria), where cellular respiration takes place (the breakdown of sugars to produce energy for the cell, a process that uses oxygen and produces carbon dioxide and water) • smooth endoplasmic reticulum where lipids are made • rough endoplasmic reticulum where proteins are made with the help of ribosomes Plants Only • chloroplast which uses light energy to convert six carbon dioxide molecules into one organic six-carbon sugar • cell wall outside the cell membrane which provides additional strength • vacuole, a large organelle containing water, often with dissolved pigments, waste materials, or other substances Blood Cells and Fat Cells (S.E.M) Cells killing another cell Review (Answer in your notes) • What are the four classes of large organic molecules found in living things? • Name two inorganic molecules that commonly occur in living things. • Name the 6 most common elements found in living organisms. • Carbohydrates/Lipids/Proteins/Nucleic Acids • Water, Sodium Chloride • H2O, NaCl • CHNOPS: carbon, hydrogen, nitrogen, oxygen, phosphorous, sulfur Drawing Cells • Refer to a textbook to draw a simple diagram of an animal cell. Draw to scale and label the following structures: • • • • • • • • Nucleus Mitochondrion Cell membrane Cytoplasm Ribosome Rough endoplasmic reticulum (rough ER) Smooth endoplasmic reticulum (smooth ER) Golgi apparatus Drawing Cells • Refer to a textbook to draw a simple diagram of a plant cell. Draw to scale and label the following structures: • • • • • • • • • • • Cell membrane Cell wall Chloroplast Cytoplasm Mitochondrion Nucleus Ribosome Vacuole Rough endoplasmic reticulum (rough ER) Smooth endoplasmic reticulum (smooth ER) Golgi apparatus Homework: Draw both cells and complete the “To Do” and answer the question below • Note that drawings can be misleading. • For example, a drawing typically shows one or a few mitochondria in a cell, but cells actually contain many mitochondria, sometimes 10,000 or more. • Also, drawings are two-dimensional whereas cells are three-dimensional. • To Do In your drawings, briefly note the functions of each organelle. • Question How are plant cells different from animal cells? In what ways are they similar? Animal Cell vs. Plant Cell Animal vs. Plant Cell • Create a Venn diagram that shows the similarities and differences between plant and animal cells All Cells Have: • Cell membrane • Cytoplasm • Cytoskeleton • Ribosomes Write the definitions in your notes, p. 56 SOL Prokaryotic and Eukaryotic • Investigate and distinguish between eukaryotes and prokaryotes based on observations of size, presence of a defined nucleus, and the presence of organelles. Prokaryotic Cells (before-kernel or pre-nucleus) • Write definition in your notes p. 57 • Do these kinds of cells have a membranebounded organelles, including a nucleus? • Are prokaryotes simple and ancient? • Did prokaryotes evolve before eukaryotes? • Are bacteria prokaryotes? • Are prokaryotes able to live in a variety of environments? Prokaryotic Cells • Kingdoms: Archaebacteria and Eubacteria • No membrane-bound organelles • Enzymes and ribosomes move around the cytoplasm freely • Genetic material is a single, circular strand of DNA • Have a cell wall around the cell membrane • Do prokaryotes have a cytoskeleton? • How do these cells keep their shape? • Describe prokaryotic flagella Cell Wall • Write definition in your notes, p. 57 • List organisms that also have a cell wall but are eukaryotic Eukaryotic (well-kernel or with nucleus) • • • • • Cells with a defined, membrane-bound nucleus Nucleus Organelle Write out definitions in your notes p. 58 Cytoplasm: contains everything inside the cell membrane but outside the nucleus • List the major organelles seen in Fig. 7 Cytoskeleton • • • • • What is the cytoskeleton? What is it made of? List some of its functions List the 3 kinds of cytoskeleton fibers List the functions of each of these fibers Cell Membrane p. 60 • • • • • Is the cell membrane rigid or fluid? What is selective permeability? Define phospholipid Define lipid bilayer Draw a cell membrane phospholipid bilayer and label the polar heads and the non-polar tails Cell Membrane Chemistry • What do the non-polar lipid tails repel? • What do these tails allow to pass? • How do membrane proteins stay in the bilayer? (p. 61) • Can proteins move around in the membrane? • Name 4 kinds of proteins that are found in cell membranes and give their functions Organelle Structure-Function Chart (SOL answers follow) Organelle Animal Plant Structure Function SOL Structure and Function of Cell Organelles Relate the following essential cell structures to their functions: • nucleus (contains DNA, site where RNA is made) • ribosomes (site of protein synthesis) • mitochondria (site of cell respiration) • chloroplast (site of photosynthesis) • endoplasmic reticulum (transports materials through the cell) • Golgi apparatus (cell products packaged for export) • lysosomes (contain digestive enzymes) • cell wall (provides support) Plasma Membrane • A lipid/protein/ carbohydrate complex, providing a barrier and containing transport and signalling systems. Nucleus • Double membrane surrounding the chromosomes and the nucleolus. Pores allow specific communication with the cytoplasm. The nucleolus is a site for synthesis of RNA making up the ribosome Mitochondria • Surrounded by a double membrane with a series of folds called cristae. Functions in energy production through metabolism. Contains its own DNA, and is believed to have originated as a captured bacterium. Chloroplasts (plastids) • Chloroplasts (plastids) Surrounded by a double membrane, containing stacked thylacoid membranes. Responsible for photosynthesis, the trapping of light energy for the synthesis of sugars. Contains DNA, and like mitochondria is believed to have originated as a captured bacterium. Rough endoplasmic reticulum (RER) • A network of interconnected membranes forming channels within the cell. Covered with ribosomes (causing the "rough" appearance) which are in the process of synthesizing proteins for secretion or localization in membranes. • Ribosomes Protein and RNA complex responsible for protein synthesis Smooth endoplasmic reticulum (SER) • A network of interconnected membranes forming channels within the cell. A site for synthesis and metabolism of lipids. Also contains enzymes for detoxifying chemicals including drugs and pesticides. Golgi apparatus • A series of stacked membranes. Vesicles (small membrane surrounded bags) carry materials from the RER to the Golgi apparatus. Vesicles move between the stacks while the proteins are "processed" to a mature form. Vesicles then carry newly formed membrane and secreted proteins to their final destinations including secretion or membrane localization. Lysosymes • A membrane bound organelle that is responsible for degrading proteins and membranes in the cell, and also helps degrade materials ingested by the cell. Vacuoles • Membrane surrounded "bags" that contain water and storage materials in plants. Peroxisomes or Microbodies • Produce and degrade hydrogen peroxide, a toxic compound that can be produced during metabolism Cell wall • Plants have a rigid cell wall in addition to their cell membranes.