Ch 4

• The cell theory: it states the importance of cells to life, all organism are composed of one or more cells, other cells come from pre-existing cells
• Phospholipid bilayer has hydrophilic heads on both sides and hydrophobic tails in between.
• Cell: smallest unit of life that can function independently and perform necessary functions of life
• Organism are either: singled cell -bacteria and archaea, or multi-celled - plants, animals and most fungi
• Prokaryotic cells: lack a nucleus, no organelles, include batería and archaea
• Eukaryotic cells: DNA is contained in a nucleus, has organelles, includes plants, animals, finfo and protista.
• Plasma membrane: separates living cells from its non living surrounding, composed of phospholipids, specific proteins are embedded in phospholipids bilayer
• Cytosol: a thick jelly like fluid inside the cell in which cellular components are suspended
• Chromosome: carry genes made of DNA
• Ribosomes: tiny structures that build proteins according to the instructions from the DNA
• Fluid mosaic: fluid because molecules can move freely pas one another, mosaic because of the diversity of proteins in the membrane
• Nucleus: control center of the cell, stores genetic information
• Nucleus: separated from cytoplasm by a double membrane(nuclear envelope), pores in envelope allows material in and out
• Nucleolus: where ribosomes are made
• Ribosome: makes protein synthesis, suspended in cytoplasm or attached to the ER
• Endoplasmic Reticulum (ER): one of the main manufacturing facilities in the cell, composed of rough ER and smooth ER
• Rough ER: protein synthesis and modification, uses transport veaicles
• Smooth ER: produces lipids, including steroids, produces detoxifying enzymes
• Golgi Apparatus: works in partnership with the ER, receives, refines stores, and distributes chemical products of the cell, uses transport vesicels
• lysosomes: membrane bound sacs of digestive enzymes found in animal cells, can break down proteins, polysaccharides, fats, nucleic acids, entire organelles and harmful bacteria
• Vacuoles: large sacs made of membrane, stores food, contractile vacuoles pul out excess water from the cell
• Vacuoles in plants: store organic nutrients, absorb water, contain pigment or poisons
• Chloroplasts: unique to photosynthetic cells of plants and algae, site of photosynthesis, produce chemical energy(sugar)
• Mitochondria: found in almost all eukaryiotic cells, organelles of cellular respiration, produce ATP
• Cell Wall: plant cell have rigid cell walls surrounding the plasma membrane, protects the cells, maintain cell shape, keeps cell from absoring too much water
• Cytoskeleton: network of fivers extending throughout the cytoplasm, provides mechanical support to the cell, helps maintain cell shape