All about CELLS! 12F recognize that according to cell theory all organisms are composed of cells and cells carry on similar functions such as extracting energy from food to sustain life 12C recognize levels of organization in plants and animals, including cells, tissues, organs, organ systems and organisms 12D differentiate between structure and function in plant and animal cell organelles, including cell membrane, cell wall, nucleus, cytoplasm, mitochondrion, chloroplast and vacuole
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All living things are made of cells A cell is the simplest structure of living things If an organism is unicellular, all functions of life happen within that one cell. If an organism is multicellular, the different cells have different jobs and they all work together
Simple Organisms Some organisms are simple: they are not particularly specialized and complicated in structure (think microscopic) These cells are organisms that function independently For example: Bacteria, Archaea, most protists (unicellular)
Complex Organisms Some organisms are more complex: Complex means that different parts of the organism performs different functions. Examples: humans, dogs, fish, mushrooms, oak trees, etc.
Organization in a complex organism: Structure and function work together Structure is the way something is made, function is the job it performs Structures join together to form systems Systems have specific functions due to the interactions between the parts At each level of structure, the interaction among the systems become more complex and more functions become possible
Complex organization order Cells form tissue Tissue made of similar cells doing a single job Organ different kinds of tissues that work together Organ system a group of organs working together Complex organism Then remember that this single organism is part of a population, community, ecosystem and biome!
Growth of an organism How do living things grow? Organisms grow by adding (making) more cells, not by increasing the size of their cells
A brief note on Mitosis and Meiosis: Cell Division Video
What do cells look like? The word cell is Latin for small room They look as varied as the organisms they build (make up) Red Blood cell Stem Cell Brain cell Plant cell
Cells have structure and function Within the cell, there are parts that each have jobs or functions These parts or structures are called organelles Examples of organelles: Nucleus, mitochondria
If cells are so small how do we know about them? While the invention of the telescope made the Cosmos accessible to human observation, the microscope opened up smaller worlds, showing what living forms were composed of.
The microscope led to the discovery of cells A. 1665 Robert Hooke published a book that described the cell 1. He looked at cork (a plant) under the microscope (30x) 2. He noticed little compartments, which he named cells because they resembled the little rooms that monks lived in
More B. 1675 Anton Van Leeuwenhoek is considered the father of microscopy because of the advances he made in microscope design and use. 1. He looked at pond water under the microscope (300x) and noticed that the water was full of moving living things 2. He made the most advanced microscope of his time
The Cell Theory was created! With the invention of the microscope and the contributions of many scientists, a very important question was answered in the 1850 s. The question was: Where do cells come from? the answer? Cell Theory!!
Forward Thinkers The Cell Theory was developed from three German scientist's discoveries. They are Matthias Schleiden, Theodor Schwann, and Rudolph Virchow. In 1838 the German Botanist Matthias Schleiden discovered that all plants were composed of cells. Then only a year later a German zoologist, Theodor Schwann, discovered that all animals were composed of cells. Later in 1855 a German physician named Rudolph Virchow was doing experiments with diseases when he found that all cells come from other existing cells. Schleiden Schwann Virchow
Cell Theory (First Version) There are 3 main concepts: 1. All living things are composed of cells 2. Cells come from other (pre-existing) cells 3. Cells are the basic structure of living things
More has been added: The modern version of the Cell Theory also includes the ideas that: All energy flow (metabolism & biochemistry) of life occurs within cells. Cells contains hereditary information which is passed from cell to cell during cell division. All cells have the same basic chemical composition.
More on the types of cells Eukaryotes larger, membrane bound organelles Prokaryotes smaller, simpler and free floating DNA
Structure Function (within cell organelles) Cell membrane - gatekeeper - surrounds and protects the cytoplasm of plant and animal cells; allows specific substances into and out of the cell Cell wall -stiff outer barrier of a plant cell; protects cell and gives structure to the plant like the skeletal system of an animal Nucleus control center contains the DNA of the cell and controls the processes of the cell Cytoplasm - gel-like fluid that fills the cell allowing movement within the cell and contains organelles such as mitochondria, chloroplasts, and vacuoles.
Structure Function (within cell organelles) Mitochondria powerhouse transforms sugar molecules into energy during the process of cellular respiration distinguish breathing (exchange of gases) from cellular respiration (release of energy from food). Chloroplasts - contains chlorophyll that is needed to transform energy from the sun into sugar molecules (glucose) during photosynthesis Vacuole - formed from and joins with the cell membrane to store food, water, or waste
Plant cells Circle the main organelles on your diagram: Cell wall Cell membrane Chloroplasts Large vacuole
Plant cells Plant cells differ from animal cells in structure and function Cell walls support Chloroplasts photosynthesis Large vacuoles store water, turgor pressure provides support to the plant
Animal cells Circle the main organelles on your diagram: Cell membrane nucleus mitochondrion
Where do they get energy? So where do plant cells and animal cells get their energy? In plants, these energy factories are called chloroplasts. They collect energy from the sun and use carbon dioxide and water in the process called photosynthesis to produce sugars. Animals can make use of the sugars provided by the plants in their own cellular energy factories, the mitochondria.
All About Cells Reading Read and answer the questions
(If time) Videos: http://viewpure.com/offhhcvasha (3 min.) Beginning of Life Plant cells: https://www.youtube.com/watch?v=cj8ddthgjby Animal Cells: https://www.youtube.com/watch?v=cj8ddthgjby