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Ch3
Cells
| Term | Definition |
|---|---|
| Cells | Smallest living subunits of a multicellular organism |
| Cell/plasma membrane | Only allows certain substances to cross |
| Cholesterol | Embedded in the membrane, decreases fluidity stabilizing the membrane |
| Proteins | Form antigens when combined with oligosaccharides |
| Oligosaccharides | Act as receptor sites for hormones or other compounds |
| Nucleus | Contains chromosomes |
| Cytoplasm | Liquid solution of dissolved minerals, gases, and other molecules |
| Organelles | Organs of the cell |
| Ribosomes | Made of protein and rRNA |
| Endoplasmic reticulum | Membranous tubules that extends from the nuclear membrane to the cell membrane |
| Rough ER | Ribosomes on the surface |
| Smooth ER | No ribosomes on the surface |
| Golgi apparatus | Flat membranous sacs stacked like pancakes |
| Mitochondria | Power house of the cell |
| Lysosomes | Contains digestive enzymes called lysozymes |
| Centrioles | Organize spindle fibers that separate chromosomes during cell division |
| Cytoskeleton | The supporting framework of the cell |
| Cilia | Beat in unison causing a wave like motion to move things across the surface |
| Flagella | Mobile threadlike projection through the cell membrane |
| Microvilli | Folds of the cell membrane that increase surface area |
| Vacuoles | Pinched off plasma membrane during phagocytosis and pinocytosis |
| Cellular transport mechanisms | Mechanisms to move substances in and out of the cell |
| Diffusion | Movement of molecules from an area of greater concentration to an area of lesser concentration along a concentration gradient until equilibrium is reached |
| Osmosis | Diffusion of water through a selectively permeable membrane |
| Isotonic solution | Equal concentration of solutes |
| Hypotonic solution | Lower concentration of solutes |
| Hypertonic solution | Higher concentration of solutes |
| Facilitated diffusion | Diffusion of molecules through a membrane with help from proteins in the cell membrane called transporters or carrier enzymes |
| Filtration | Substances are forced through a membrane by mechanical pressure |
| Active transport | Energy requiring process of moving molecules against a concentration gradient |
| Phagocytosis | Moving cell engulfs something |
| Pinocytosis | Stationary cell engulfs something |
| Exocytosis | When a cell releases contents outside the cell |
| DNA | Double strand of nucleotides twisted into a double helix made up of Adenine, thymine, guanine, cytosine |
| Adenine | Only pairs with thymine |
| Guanine | Only pairs with cytosine |
| Sequence of A, T, G, C | Determines the genetic code |
| Genome | The entire genetic code |
| Gene | The genetic code for one protein |
| RNA | Similar to DNA except, single-strand, has a U in place of T |
| MRNA | Messenger RNA |
| TRNA | Transfer RNA |
| RRNA | Ribosomal RNA |
| Protein synthesis | Occurs in the ribosomes |
| Proteins | Chains of amino acids |
| Transcription | Messenger RNA is created from instructions on the DNA |
| Translation | TRNA attaches to the mRNA at a site on the tRNA called the anticodon which has complementary bases to the codon on the mRNA |
| Mitosis and meiosis | Two types of cell division |
| Mitosis | One cell divides into two identical cells both having a full set of chromosomes |
| Diploid number | Full set of chromosomes |
| Stages of mitosis | Interphase, prophase, metaphase, anaphase, telophase |
| Interphase | DNA replication |
| Prophase | Chromosomes coil up, nuclear membrane disappears, centrioles move to opposite ends and extends spindle fibers to the chromosomes |
| Metaphase | Chromosomes line up in the middle, Centromere's attach to the spindle fibers and divide |
| Anaphase | Spindle fibers pull chromosomes to each pole |
| Telophase | Chromosomes uncoil to become chromatin, nuclear membrane reforms |
| Cytokinesis | Cytoplasm divides and cell membrane closes off |
| Meiosis | One cell divides into four cells each having half of the chromosomes |
| Meiosis in women | Occurs in the ovaries |
| Meiosis in men | Occurs in the testes |
| Meiosis phases | Same as mitosis but all happens twice except for Interphase |