THE CELL AND CELLULAR ENVRIONMENT

Cell Basic structural unit of all plants and animals A membrane enclosing a thick fluid and a nucleus Specialized to carry out all the bodys basic functions

Procaryot Single-cell organism Single-cell organism Bacteria Bacteria Structures Structures Cell membrane Cytoplasmic matrix Nucleoid Cell wall

Cell Membrane Absolute requirement for all living organisms Absolute requirement for all living organisms Cells must interact in a selective fashion with their enviornment Cells must interact in a selective fashion with their enviornment Cells must acquire nutrients, eliminate waste and maintain their internal environment based on external changes Cells must acquire nutrients, eliminate waste and maintain their internal environment based on external changes Encompasses the cytoplasm Encompasses the cytoplasm

Cytoplasmic matrix Lacks organelles Lacks organelles Subtance that lies between the plasma membrane and the nuceloid Subtance that lies between the plasma membrane and the nuceloid Largely water Largely water about 70% of bacterial mass is water Often packed with ribosomes Often packed with ribosomes made of protein and RNA protein synthesis {building of proteins}

The nucleoid Where the DNA is located Where the DNA is located DNA is a single circle, double stranded DNA is a single circle, double stranded Composed of 60% DNA, some RNA and a small amount of protein Composed of 60% DNA, some RNA and a small amount of protein

Cell Wall One of the most important parts of the procaryotic cell One of the most important parts of the procaryotic cell Gives shape Gives shape Protects from osmotic lysis Protects from osmotic lysis lysis; breaking down of a cell osmosis; movement of water

Functions of Procaryotic Structures Plasma Membrane Plasma Membrane selectively permeable barrier mechanical boundary nutrient and waste transport location of many metabolic processes detection of cues for chemotaxis

Chemotaxis Directed movements according to chemicals in their enviornment Directed movements according to chemicals in their enviornment Finding of food Finding of food Gas vacuole buoyancy Ribosomes Ribosomes protein synthesis

Periplasmic space Periplasmic space nutrient processing and uptake Cell wall Cell wallshape protection from lysis Capsules and slime layers Capsules and slime layers resistance to phagocytosis adherence to surfaces

Phagocytosis Processing of engulfing or eating such as the immune system consuming or destroying pathogens Fimbriae and pili attachement to surfaces mating Flagella movement

Endospore survival under harsh environmental conditions

The Cell

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Eucaryotic Cell Structure Multi-cell organisms Structures, characteristics and functions Cytoplasmic Matrix Cytoplasmic Matrix Endoplasmic Reticulum Endoplasmic Reticulum Golgi Apparatus Golgi Apparatus Lysosomes and endocytosis Lysosomes and endocytosis Ribosomes Ribosomes

Mitochondria Chloroplasts Nucleus and cell division External cell coverings Cilia and flagella

Eucaryotic cells contain organelles Eucaryotic cells contain organelles Organelle Organelle intracellular structures that perform specific functions

Cytoplasmic matrix Featureless, homogenous substance Featureless, homogenous substance One of the most important and complex parts of the cell One of the most important and complex parts of the cell The environment of the organelles The environment of the organelles Location of many important biochemical processes Location of many important biochemical processes Several physical changes are due to matrix functions Several physical changes are due to matrix functions

Several physical changes are due to matrix activity Several physical changes are due to matrix activityWater A eucaryotic cell is 70 to 85% water by weight A eucaryotic cell is 70 to 85% water by weight Two forms Two forms bulk or free water bound water or water of hydration

Bulk or free water Osmotically active water Osmotically active water Bound water Bound to the surface of proteins Bound to the surface of proteins Where water, nutrients and waste products can be stored Where water, nutrients and waste products can be stored

Microfilaments Structure Structure Movements Movements Form the cytoskeleton Form the cytoskeleton Contain structures such as flagella, cilia and lamellipodia. Plays important roles in transport and division.

Lamellipodia Propels the cell across a substrate Propels the cell across a substrate Endoplasmic Reticulum Transport of materials Transport of materials Protein and lipid synthesis Protein and lipid synthesis

Golgi Apparatus Packaging and secretions of materials for use within the cell Packaging and secretions of materials for use within the cell Lysosome formation Lysosome formationLysosomes Intracellular digestion Intracellular digestion

Cells need to make proteins. Those proteins might be used as enzymes or as support for other cell functions. When you need to make proteins, you look for ribosomes. Ribosomes are the protein builders or the protein synthesizers of the cell. They are like construction guys who connect one amino acid at a time and build long chains. Ribosomes are found in many places around the cell. You might find them floating in the cytoplasm (cytosol). Those floating ribosomes make proteins that will be used inside of the cell. Other ribosomes are found on the endoplasmic reticulum. Endoplasmic reticulum with attached ribosomes is called rough. It looks bumpy under a microscope. Those attached ribosomes make proteins that will be used inside the cell and proteins made for export out of the cell. cytoplasm (cytosol)endoplasmic reticulumcytoplasm (cytosol)endoplasmic reticulum

Intracellular digestion Breaking down of large molecules into smaller ones Breaking down of large molecules into smaller onesMitochondria powerhouse of the cell powerhouse of the cell Energy production Energy production

Chloroplasts Photosynthesis PhotosynthesisNucleus Ribosomal RNA synthesis Ribosomal RNA synthesis Ribosome construction Ribosome construction