62 terms

Study Guide: Anatomy & Physiology: Chapter 3

Cell Theory
Cell is the basic structural and functional unit of life
Cell Theory
Organismal activity depends on individual and collective activity of life
Cell Theory
Biochemical activities of cells are dictated by cellular structure
Cell Theory
Continuity of life has a cellular basis
Plasma Membrane
- separates intracellular fluids from extracellular fluids
- regulates entry and exit of materials
- cellular region between nuclear and plasma membrane
- contains cytosol (fluid), organelles, inclusions (stored nutrients, secretory products, pigment)
- double membrane structure with self-like cristae
- provide most of cells ATP via aerobic cellular respiration
- contains own DNA and RNA
- granules containing protein and rRNA
- site of protein synthesis
- free ribosomes synthesize soluble proteins
- membrane-bound ribosomes synthesize proteins to be incorporated into membranes
Endoplasmic Reticulum
- "network within the cytoplasm"
- interconnected tubes and parallel membranes enclosing cisternae (fluid-filled cavities)
Rough ER
- external surface studded with ribosomes
- ribosomes manufacture all proteins secreted from cell
- cell's "membrane factory" because responsible for the synthesis of integral proteins and phospholipids for cell membranes
Smooth ER
- Tubules arranged in a looping network
- Catalyzes the following reactions in various organs of the body: liver, testes, intestinal cells, skeletal/cardiac muscle
lipid and cholesterol metabolism; breakdown glycogen; detoxification of drugs------Smooth ER catalyzes
synthesis of steroid-based hormones------Smooth ER catalyzes
intestinal cells
absorption, synthesis, transport fats ------Smooth ER catalyzes
skeletal/cardiac muscle
storage/release of calcium ------Smooth ER catalyzes
Golgi Apparatus
- stacked and flattened membranous sacs
- functions in modification, concentration, packaging proteins
- transport vessels for ER, fuse with the cis face of the______
- Proteins that pass through the ________ to the trans face
- secretory vesicles leave the trans face of the ____ stack and move to designated parts of the cell
- spherical membranes bags contain enzymes
- digest ingested bacteria, viruses, toxins
- degrade nonfunctional organelles
- breakdown glycogen and release thyroid hormone
- secretory ______ found in white blood cells, immune cells, melanocytes
Endomembrane System
- system of organelles that function: produce, store, export biological molecules; degrade potentially harmful substances
-includes: nuclear envelope, smooth/rough ER, lysosomes, vacuoles, transport vesicles, golgi apparatus, plasma membrane
- membranous sacs have oxidases and catalases
- detoxify harmful/ toxic substance
- neutralize dangerous free radicals
- "skeleton of cell"
- consists of microtubules, microfilaments, intermediate filaments
- Dynamic, hollow tubes made of the spherical protein tubulin
- Determine overall shape of the cell and distribution of organelles
- strands of protein actin
- attached to cytoplasmic side of plasma membrane
- strength/brace cell surface
- attach to CAMs, function in edocytosis/ exocytosis
Intermediat filaments
- part of cytoskeleton
- resist pulling forces on cell and help form desmosomes
- pinwheel of 9 triplet of microtubules
- organize mitotic spindle during mitosis
- bases of cilla and flagella
- contains: nuclear envelope, nucleoli, chromatin
- Gene- containing control center of cell
- contains genetic library of all cellular proteins
- tells what proteins need to be synthesized
Nuclear Envelope
- double membrane barrier containing pores
- enclosed jellylike nucleoplasm has essential solutes
- Pore complex regulates transport of large molecules in/out of nucleus
- dark circle of body in nucleus
- site of ribosomes production
- DNA constitutes the genes
- threadlike material made of DNA/histone proteins
Fluid Mosaic Model
- Double bilayer of lipids with imbedded, dispersed proteins
- Bilayer consists of phospholipids, cholesterol, glycolipids

*see diagram
lipids which bond carbohydrate
have hydrophilic/phobic bipoles
- minute fingerlike extensions of plasma membrane
- increase plasma membrane surface area hugely
Tight Junction
- impermeable junction that encircles cells
anchoring junction scattered along sides of cells
Gap Junction
- nexus that allows chemical substances to pass between cells...junction
Passive Membrane Transport
- H20, Cl-, Fat, O2, Co2, Glucose
- energy not required-----diffusion
Active Membrane Transport
- Na+, K+, Amino Acids, steroid
- energy required---assisted by enzymes
- energy ATP
-Primary Active Transport
-Secondary Active transport
Cell Adhesion Molecules (CAMs)
- anchor cells to the extracellular matrix
- assist in movement of cell past on another
- rally protective white blood cells to injured or infected areas
Membrane receptors
Contact Signaling, Electrical signaling, chemical signaling
Contact Signaling
- important in normal development and immunity
=some bacteria use this signaling to identify target organ
-the actual coming together and touching of cells, means by which cells recognize one another
- membrane receptor
Electrical Signaling
- certain plasma membrane proteins are channel proteins that respond to changes in membrane potential by opening/close channel
- voltage-regulated "ion gates" in nerve and muscle tissue
- membrane receptor
Chemical Signaling
neurotransmitters bind to chemically gated channel-linked receptors in nerve and muscle tissue
- membrane receptor
Mitotic Phase
metabolic activity and vigorous growth....cell cycle
synthesis for DNA.........cell cycle
preparation for division......cell cycle
1st step
- centrioles move to poles
- spindle fibers start to form
- chromatin condense into chromosomes
- nuclear envelope breaks down
2nd step
- chromosomes meet in middle (equator)
3rd step
- chromosomes split and move to opposite poles (sides)
4th step
- two distinct nuclei, nuclear envelope reforms chromosomes unwind into chromatin
- carries genetic info from DNA in nucleus to ribosomes in cytoplasm
- bound amino acid base pair with codons of mRNA at the ribosome to begin process of protein synthesis

*see diagram
- a structural component of ribosomes
transfer of information from the sense strand of DNA to RNA
language of nucleic acids translated to language of proteins
Simple diffusion
- movement of molecules (driven by kinetic energy) down a concentration gradient
- Fat soluble solutes can diffuse directly through the membrane by dissolving in the lipid
*passive transport
Facilitated diffusion
-passive movement of certain solutes across the membrane either by their binding with a membrane carrier protein or by their moving through a membrane channel
-kinetic energy
*passive transport
diffusion of a solvent (water) through a selectively permeable membrane
-water diffuses through membrane pores (aquaporins) or directly through the lipid part of the membrane from a solution of lesser osmolarity to a solution of greater osmolarity
---particles move from crowded area to not crowded area
= water becomes more equal with even # particles
=more particles on 1 side higher water level
*passive transport
- water moves out of the cells
- water enters and exits the cells at the same rate
-water moves into the cells