information that was being carried diffuses across the narrow space‚ binding itself to the receptors found in unique membranes of the receiving cell. The neurotransmitter‚ as a mediator‚ opens the channels of a number of ion species. This then leads to a resulting difference in the transmembrane potential. At this point‚ there exists two possible scenarios‚ one in which the membrane hyperpolarizes and one in which it depolarizes. This meaning that it is either an excitatory or an inhibitory postsynaptic
Premium Nervous system Neuron Brain
an area of high concentration to an area of low concentration across a semi permeable membrane. An osmotic system is established when a semi-permeable membrane is placed between two solutions. In this biological systems context‚ osmosis is the exchange of water between the potato cell and the surrounding medium of varying sucrose concentrated solutions‚ with the plasma membrane being the semi- permeable membrane. Because water molecules have kinetic energy‚ they are constantly moving around in gaseous
Premium Osmosis Concentration Diffusion
Cell Transport Mechanisms and Permeability 1 EXERCISE 1 OBJECTIVES 1. To define the following terms: differential permeability‚ passive and active processes of transport‚ diffusion (simple diffusion‚ facilitated dif- fusion‚ and osmosis)‚ solute pump‚ pinocytosis‚ and phagocytosis. 2. To describe the processes that account for the movement of sub- stances across the plasma membrane‚ and to indicate the driving force for each. 3. To determine which way substances will move passively
Premium Diffusion Osmosis Cell membrane
three phases known as the latent‚ contraction‚ and relaxation phase. • threshold - the threshold is the minimal stimulus needed to cause a depolarization of the muscle plasma membrane (sarcolemma.) The threshold is the point at which sodium ions start to move into the cell (instead of out of the cell) to bring about the membrane depolarization. • treppe - the progressive increase in force generated when a muscle is stimulated at a sufficiently high frequency • summation - When a muscle is stimulated
Premium Neuromuscular junction Skeletal muscle Acetylcholine
Matthias Schleiden concluded that all plants were made up of cells. Theodor Schwann stated that all animals were made up of cells. Rudolf Virchow concluded that new cells could be produced only from the division of existing cells. Janet Plowe demonstrated that the cell membrane is a physical structure‚ not an interface between two liquids. Lynn Margullis proposed the idea that certain organelles were once free living themselves. Cell Theory: All living things are composed of cells. Cells are the basic units of structure and function in living things
Premium Cell
First let’s explore the city limits. Most animal cells will be patrolled by cilia or by flagella‚ both are made out of nine pairs of microtubules. Next in the tour the cell membrane which goes around the city and monitors what will enter and leave the cell. The function that allows for this to happen is called selective permeability. The cytoplasm which has inside of that the cytoskeleton made up of protein strands to back up the cell‚ kind of like a body guard. Centrosomes put the microtubules together
Premium DNA Cell Bacteria
Macromolecules that make up cell material Macromolecule | Primary Subunits | Where found in cell | Proteins | amino acids | Flagella‚ pili‚ cell walls‚ cytoplasmic membranes‚ ribosomes‚ cytoplasm | Polysaccharides | sugars (carbohydrates) | capsules‚ inclusions (storage)‚ cell walls | Phospholipids | fatty acids | membranes | Nucleic Acids (DNA/RNA) | nucleotides | DNA: nucleoid (chromosome)‚ plasmids rRNA: ribosomes; mRNA‚ tRNA: cytoplasm | Table 2. Summary of characteristics of typical
Free Bacteria Cell Protein
- Molecules move from hypertonic to hypotonic‚ until it reaches an isotonic state (or equilibrium). At that point‚ molecules will move equally across the membrane. 10-1 Cell Growth surface-area-to-volume-ratio: the ratio of surface area to volume cell division: division of a cell (also called mitosis) Explain why larger organisms are made of many small cells rather than one large cell‚ emphasizing the
Premium Eukaryote DNA Bacteria
selectively permeable membrane” (Lab Manual 2nd edition). It was hypothesized that osmosis will occur when there is an uneven distribution of solute in a solvent. The more abundant the solute is in solvent‚ the higher the rate of osmosis through the diffusion gradient forming a hypertonic or hypotonic solution. Solvent with equal or no solute forms an isotonic solution. Throughout this lab‚ data was collected and compiled to analyze these effects across selectively permeable membranes. The results indicated
Premium Semipermeable membrane Osmosis Concentration
Aeroxide® TiO2 P90 (Evonik‚ Germany) was used in all experiments as the photocatalyst. The properties of TiO2 nanoparticles are given in Table 3.1 according to the supplier. The suspensions were prepared by dispersion of the desired amount of TiO2 in deionized water. The suspension was magnetically mixed at the stirrer speed of 500 – 600 rpm. Table 3.1. Characteristic physicochemical data of Aeroxide® TiO2 P90 Properties Unit Primary particle size µm 14 Specific surface area (BET) m2/g 90 ± 20
Premium Chemistry Chemical reaction Oxygen