Chapter 3 Flashcards
Four functions of the cell?
Metabolism and energy. Synthesis of molecules. Communication. Reproduction and inheritance.
What are the basic structures of the cell?
Plasma membrane, cytoplasm, nucleus
Hydrophilic
Water loving
Hydrophobic
Water fearing
Extend deeply into membrane, often extending from one surface to the other; can form channels through the membrane
Integral (Intrinsic) Membrane Protein
Attached to integral proteins at either the inner or outer surfaces of the lipid bilayer
Peripheral (Extrinsic) Membrane Proteins
Allows cells to identify one another or other molecules
Marker Molecules
Marker Molecule examples?
Glycoproteins and glycolipids
Attach cells to other cells
Cadherins
Integral proteins that attach to extra cellular molecules
Integrins
Transport proteins include?
Channel proteins, carrier proteins, and ATP-powered pumps.
Nongated ion channels are:
Always open
Responsible for the permeability of the plasma membrane to ions when the plasma membrane is at rest
Nongated Ion Channels
Two examples of gated ion channels are?
Ligand gated and voltage-gated
Gated ion channels can be:
Opened or closed by certain stimuli
Open in response to small molecules that bind to proteins or glycoproteins
Ligand Gated Ion Channel
Open when there is a change in charge across the plasma membrane
Voltage-Gated Ion Channel
Carrier proteins are also called?
Transporters
Have specific binding sites; protein changes shape to transport ions or molecules; resumes original shape after transport
Carrier Proteins
Moves one particles
Uniporters
Move two particles in the same direction at the same time
Symporters
Move two particles I’m opposite directions at the same time
Antiporters
Attach to specific chemical signal molecules and act as an intercellular communication system
Receptor Proteins
Movement of solutes from an area of higher concentration to lower concentration in solution
Diffusion
Difference between two points
Concentration
How easily a liquid flows
Viscosity
Diffusion of water (solvent) across a selectively permeable membrane. Water moves from an area of low concentration of solute to an area of high concentration of solute.
Osmosis
Force required to prevent water from moving across a membrane by osmosis
Osmotic Pressure
Solutions with the same concentrations of solute particles
Isosmotic
Solution with a greater concentration of solute
Hyperosmotic
Solution with a lesser concentration of solute
Hyposmotic
Cell neither shrinks nor swells
Isotonic
Cell shrinks
Hypertonic
Cell swells
Hypotonic
Characteristics of mediated transport are?
Specificity, competition, and saturation
Move large, water soluble molecules or electrically charged molecules across the plasma membrane
Facilitated Diffusion
The use of energy allows the cell to accumulate substances. Rate of transport depends on concentration of substrate and on concentration of ATP.
ATP-Powered Transport
Internalization of substances by formation of a vesicles
Endocytosis
Types of Endocytosis are?
Phagocytosis, pinocytosis, and receptor-mediated endocytosis
Accumulated vesicle secretions expelled from the cell
Exocytosis
Cellular material outside nucleus but inside plasma membrane
Cytoplasm
Cytoplasm is composed of:
Cytosol, cytoskeleton, cytoplasmic inclusion, and organelles
Cytosol is the _________ of the cell.
Fluid portion
Ions in water
Dissolved molecules
Proteins in water
Colloid
The cytoskeleton contains what?
Microtubules, microfilaments, intermediate filaments, cytoplasmic inclusions
Hollow, made of tubulin; internal scaffold, transport, cell division
Microtubules
Actin; structure, support for microvilli, contractility, movement.
Microfilaments
Mechanical strength
Intermediate filaments
Aggregates of chemicals such as lipid droplets, melanin
Cytoplasmic inclusions
What does the nucleolus contain?
RNA
What makes up the nucleus?
Nucleoplasm, nucleolus, and nuclear envelope
Is DNA acidic or basic?
Acidic
Are histones acidic or basic?
Basic
Histones are?
Proteins found in chromatin.
DNA complexed with proteins called histones.
Chromatin
Pairs of chromatin.
Chromatid
Pairs of chromatid make up?
Chromosomes.
Chromatids are joined together by the?
Centromere
What is the site of protein synthesis?
Ribosomes.
Types of Ribosomes?
Free and attached.
Free ribosomes are located where?
Floating around in the cell.
Attached ribosomes are found where?
Rough Endoplasmic Reticulum
Two types of Endoplasmic Reticulum.
Rough and smooth
Rough Endoplasmic Reticulum produce and modify what?
Proteins wit the help of ribosomes.
Smooth Endoplasmic Reticulum produce what?
Lipids and carbohydrates.
Interior spaces isolated from rest of cytoplasm.
Cisternae
The __________ is in charge of modification, packaging, distribution of proteins and lipids for secretion or internal use.
Golgi Apparatus.
Lysosomes are essentially the?
Clean up crew.
Smaller than lysosomes; contain enzymes to break down fatty acids and amino acids; hydrogen peroxide is a by-product of breakdown.
Peroxisomes
Consists of large protein complexes; include several enzymes that break down and recycle proteins in cell.
Proteasomes
Site of ATP synthesis.
Mitochondria
Infoldings of inner membrane of mitochondria
Cristae
Substance located in space formed by inner membrane of mitochondria.
Matrix
Moves materials over the cell surface
Cilia
Move the cell
Flagella
Flagella has a ______ microtuble arrangement.
9 + 2
Extensions of plasma membrane and increase the cell surface area
Microvilli