Cells Structure & Function PDF

Cells Smallest living unit Most are microscopic Principles of Cell Theory All living things are made of cells Smallest living unit of structure and function of all organisms is the cell All cells arise from pre-existing cells Which came first, the chicken or the egg? Explain. Cell S...

Cells Smallest living unit Most are microscopic Principles of Cell Theory All living things are made of cells Smallest living unit of structure and function of all organisms is the cell All cells arise from pre-existing cells Which came first, the chicken or the egg? Explain. Cell Size A bacteria is smaller than a virus. True False Characteristics of All Cells A surrounding membrane Organelles – structures for cell function Control center with DNA  Cell Types Prokaryotic (bacteria) no organelles other than ribosomes, have cell walls Eukaryotic  Eukaryotic Cells Nucleus bound by membrane Include fungi, protists, plant, and animal cells Possess many organelles Protozoan Representative Animal Cell Representative Plant Cell An animal cell has a cell wall. True False  Plasma Membrane Contains cell contents Double layer of phospholipids & proteins  Cell Walls Found in plants, fungi, & many protists Surrounds plasma membrane  Cytoplasm Viscous fluid containing organelles components of cytoplasm – Interconnected filaments & fibers – Fluid = cytosol – Organelles (not nucleus) – storage substances  Cilia & Flagella Provide motility Cilia – Short – Used to move substances outside human cells Flagella – Whip-like extensions – Found on sperm cells  Centrioles Pairs of microtubular structures Play a role in cell division All animal cells have, all higher level plants do not  Nucleus Control center of cell Double membrane Contains – Chromosomes (DNA) – Nucleolus  DNA Hereditary material Chromosomes – DNA – Protiens – Form for cell division Chromatin (spaghetti like-DNA is kept like this when not dividing)  Nucleolus Directs synthesis of RNA Forms ribosomes The nucleolus is smaller than the nucleus. True False  Endoplasmic Reticulum Helps move substances within cells Network of interconnected membranes Two types – Rough endoplasmic reticulum – Smooth endoplasmic reticulum Rough Endoplasmic Reticulum Ribosomes attached to surface – Manufacture proteins – Not all ribosomes attached to rough ER May modify proteins from ribosomes  Smooth Endoplasmic Reticulum Looks very similar to rough, but does NOT have ribosomes attached-builds carbohydrates and lipids  Golgi Apparatus Involved in synthesis of plant cell wall Packaging & shipping station of cell Golgi Apparatus Function 1. Molecules come in vesicles 2. Vesicles fuse with Golgi membrane 3. Molecules may be modified by Golgi  Golgi Apparatus Function (Continued) 4. Molecules pinched-off in separate vesicle 5. Vesicle leaves Golgi apparatus 6. Vesicles may combine with plasma membrane to secrete contents The golgi apparatus is longer than the ER. True False  Lysosomes Contain digestive enzymes Functions – Aid in cell renewal – Break down old cell parts – Digests invaders  Vacuoles Membrane bound storage sacs More common in plants than animals Contents – Water – Food – wastes  Mitochondria Have their own DNA Bound by double membrane  Mitochondria Break down fuel molecules (cellular respiration) – Glucose – Fatty acids Release energy – ATP  Chloroplasts Derived form photosynthetic bacteria Solar energy capturing organelle  Photosynthesis Takes place in the chloroplast Makes cellular food – glucose Photosynthesis occurs in algae. True False