Lecture 5 The Cell membrane and Membrane Proteins The cell
... -storage of electrical potential energy • This potential energy can be tapped into by the cell to carry out work • eg.: the diffusion of H+ ions back down their electrochemical gradient can be coupled to the active transport of Sucrose against its concentration gradient ...
... -storage of electrical potential energy • This potential energy can be tapped into by the cell to carry out work • eg.: the diffusion of H+ ions back down their electrochemical gradient can be coupled to the active transport of Sucrose against its concentration gradient ...
How Neurons Talk to Each Other
... The presynaptic nerve endings contain signal molecules known as neurotransmitters, which are stored in small membrane-enclosed vesicles. Each nerve ending in the central nervous system contains an average of several hundred synaptic vesicles. However, synapses vary significantly. For example, some s ...
... The presynaptic nerve endings contain signal molecules known as neurotransmitters, which are stored in small membrane-enclosed vesicles. Each nerve ending in the central nervous system contains an average of several hundred synaptic vesicles. However, synapses vary significantly. For example, some s ...
File - medicalfocus tanzania home of health professional
... body parts, are composed of chemicals made up of submicroscopic particles called atoms. Atoms join to form molecules, which can in turn join to form macromolecules. For example, molecules called amino acids join to form a macromolecule called protein, which makes up the bulk of our muscles. Macromol ...
... body parts, are composed of chemicals made up of submicroscopic particles called atoms. Atoms join to form molecules, which can in turn join to form macromolecules. For example, molecules called amino acids join to form a macromolecule called protein, which makes up the bulk of our muscles. Macromol ...
Study Guide
... 1. Which of the following is not a muscle of the hamstring group?: (5.1.12.D.3) a. gracilis b. semitendinosus c. quadriceps femoris d. biceps femoris e. semimembranosus 2. The primary muscle used in doing a sit-up is the ___?: (5.1.12.D.3) a. erector spinae. b. splenius capitis. c. splenius cervicis ...
... 1. Which of the following is not a muscle of the hamstring group?: (5.1.12.D.3) a. gracilis b. semitendinosus c. quadriceps femoris d. biceps femoris e. semimembranosus 2. The primary muscle used in doing a sit-up is the ___?: (5.1.12.D.3) a. erector spinae. b. splenius capitis. c. splenius cervicis ...
E4 - Neurotransmitters and Synapses - IBDPBiology-Dnl
... neurone(a)has a high frequency of action potentials arriving at the synapse. This sends a number of waves of neurotransmitter to depolarise the post synaptic membrane. Waves of depolarisation (from one neurone) are added together to reach threshold ...
... neurone(a)has a high frequency of action potentials arriving at the synapse. This sends a number of waves of neurotransmitter to depolarise the post synaptic membrane. Waves of depolarisation (from one neurone) are added together to reach threshold ...
True or False Questions - Sinoe Medical Association
... TF 4. During embryogenesis, the notochord induces the formation of the neuroectoderm in the overlying ectoderm. TF 5. The peripheral nervous system develops from the cells of the neural tube. TF 6. At the equilibrium potential for a permeant ion, the flux of the ion down its concentration gradient i ...
... TF 4. During embryogenesis, the notochord induces the formation of the neuroectoderm in the overlying ectoderm. TF 5. The peripheral nervous system develops from the cells of the neural tube. TF 6. At the equilibrium potential for a permeant ion, the flux of the ion down its concentration gradient i ...
Feedback — Exam
... (recorded at the post synaptic cell following presynaptic activation) is reduced. In cortical/hippocampal pyramidal cells, when the pre synaptic cell fires a spike before the post synaptic cell – the excitatory synapses between these cells is strengthened (LTP) and vice-versa for synaptic weakening ...
... (recorded at the post synaptic cell following presynaptic activation) is reduced. In cortical/hippocampal pyramidal cells, when the pre synaptic cell fires a spike before the post synaptic cell – the excitatory synapses between these cells is strengthened (LTP) and vice-versa for synaptic weakening ...
Membrane transport
... The schematic is for a drug exporter. The drug-binding site (red) is high-affinity and faces the inner leaflet of the membrane. Step I: the transport cycle is initiated by binding of substrate to its high-affinity site on the TMDs from the inner leaflet of the membrane. The affinity of the NBDs for ...
... The schematic is for a drug exporter. The drug-binding site (red) is high-affinity and faces the inner leaflet of the membrane. Step I: the transport cycle is initiated by binding of substrate to its high-affinity site on the TMDs from the inner leaflet of the membrane. The affinity of the NBDs for ...
Neurons and Neurotransmitters
... Myelin Sheath: a layer of fatty cells encasing the fibers of many axons which allows faster transmission speeds in neurons. ...
... Myelin Sheath: a layer of fatty cells encasing the fibers of many axons which allows faster transmission speeds in neurons. ...
Neuroscience in PT: Introduction and Review
... • Found mostly outside the nervous system in mast cells that mediate immune responses and allergic reactions. • Role of histamine in the brain – Maintain the alert state – Excitatory effects on thalamus Antihistamine medications can cause ...
... • Found mostly outside the nervous system in mast cells that mediate immune responses and allergic reactions. • Role of histamine in the brain – Maintain the alert state – Excitatory effects on thalamus Antihistamine medications can cause ...
Chapter 28
... “depolarized,” becoming more positive. • The open Na+ channels in the small patch of depolarized membrane remain open for only one half of a millisecond. • If the voltage change of the depolarization is great enough, it causes nearby voltage-gated Na+ and K+ channels to open. ...
... “depolarized,” becoming more positive. • The open Na+ channels in the small patch of depolarized membrane remain open for only one half of a millisecond. • If the voltage change of the depolarization is great enough, it causes nearby voltage-gated Na+ and K+ channels to open. ...
Active transport
... Can transport up to 100 million ions per second, a rate 105 times greater than that mediated by a carrier protein ...
... Can transport up to 100 million ions per second, a rate 105 times greater than that mediated by a carrier protein ...
Unit 1 – Nervous and Endocrine System
... Neurons are the basic unit of the nervous system Neurons are similar to other cells in the body because they are surrounded by a cell membrane. have a nucleus that contains genes. contain cytoplasm, mitochondria and other organelles. carry out basic cellular processes such as protein syn ...
... Neurons are the basic unit of the nervous system Neurons are similar to other cells in the body because they are surrounded by a cell membrane. have a nucleus that contains genes. contain cytoplasm, mitochondria and other organelles. carry out basic cellular processes such as protein syn ...
General Neurophysiology
... Reduced the animal to a head and the floor of the thorax and the thoracic nerve cord Elecrodes on the stumps of the nerves that had innervated the ...
... Reduced the animal to a head and the floor of the thorax and the thoracic nerve cord Elecrodes on the stumps of the nerves that had innervated the ...
Neural Communication
... • THIS MEANS THE ACTION POTENTIAL FROM THE PRESYNAPTIC NEURON INCREASES THE LIKLIHOOD THAT AN ACTION POTENTIAL WILL BE GENERATED IN THE POSTSYNAPTIC NEURON. • THIS CAUSES THE FIRING OF NERVE IMPULSES. • NEURONS THAT FIRE TOGETHER ARE LIKLEY TO WIRE TOGETHER. • WHEN THEY WIRE TOGETHER THEY FORM NEURA ...
... • THIS MEANS THE ACTION POTENTIAL FROM THE PRESYNAPTIC NEURON INCREASES THE LIKLIHOOD THAT AN ACTION POTENTIAL WILL BE GENERATED IN THE POSTSYNAPTIC NEURON. • THIS CAUSES THE FIRING OF NERVE IMPULSES. • NEURONS THAT FIRE TOGETHER ARE LIKLEY TO WIRE TOGETHER. • WHEN THEY WIRE TOGETHER THEY FORM NEURA ...
ppt - Castle High School
... Steps of muscle contraction 1. Electric signal sent from brain down motor neuron to neuromuscular junction 2. Neurotransmitter signal sent from neuron received by sarcolemma of muscle cell 3. Calcium ion movement into muscle cell 4. Myosin forms cross bridges with actin 5. ATP allows cross bridges ...
... Steps of muscle contraction 1. Electric signal sent from brain down motor neuron to neuromuscular junction 2. Neurotransmitter signal sent from neuron received by sarcolemma of muscle cell 3. Calcium ion movement into muscle cell 4. Myosin forms cross bridges with actin 5. ATP allows cross bridges ...
BLoA Neurotransmission
... between the two neurons. The change in potential is going to affect little vesicles, little blobs of membrane inside the presynaptic neuron. These vesicles contain the neurotransmitters, which are synthesized in the presynaptic cell, and stored in the vesicles ...
... between the two neurons. The change in potential is going to affect little vesicles, little blobs of membrane inside the presynaptic neuron. These vesicles contain the neurotransmitters, which are synthesized in the presynaptic cell, and stored in the vesicles ...
nervous system - Mrothery.co.uk
... tendons (connective tissue comprised almost entirely of collagen) Muscles can only produce contraction. Therefore at least two muscles of sets of muscles must be used to move a bone into one position and back again (called antagonistic muscles) e.g., biceps and triceps. In order for the CNS to co-or ...
... tendons (connective tissue comprised almost entirely of collagen) Muscles can only produce contraction. Therefore at least two muscles of sets of muscles must be used to move a bone into one position and back again (called antagonistic muscles) e.g., biceps and triceps. In order for the CNS to co-or ...
PowerLecture: Chapter 13
... array of proteins, ions, and other molecules in a neuron, both at rest and as a neuron experiences a change in potential. Understand how a nerve impulse is received by a neuron, conducted along a neuron, and transmitted across a synapse to a neighboring neuron, muscle, or gland. ...
... array of proteins, ions, and other molecules in a neuron, both at rest and as a neuron experiences a change in potential. Understand how a nerve impulse is received by a neuron, conducted along a neuron, and transmitted across a synapse to a neighboring neuron, muscle, or gland. ...
Chapter 48 Nervous Systems
... Gated Na+ channels open, Na+ diffuses into the cell, and the inside of the membrane becomes less negative. These changes in membrane potential are called graded potentials because the magnitude of the change—either hyperpolarization or depolarization—varies with the strength of the stimulus. A l ...
... Gated Na+ channels open, Na+ diffuses into the cell, and the inside of the membrane becomes less negative. These changes in membrane potential are called graded potentials because the magnitude of the change—either hyperpolarization or depolarization—varies with the strength of the stimulus. A l ...
Hearing
... - Tectorial membrane: bends over the hair cells - Hair cells: organized stereocilia on their apical surface, connected with a protein fiber (tip link). 3 row outer ...
... - Tectorial membrane: bends over the hair cells - Hair cells: organized stereocilia on their apical surface, connected with a protein fiber (tip link). 3 row outer ...
VI. The vertebrate nervous system is a hierarchy of structural and
... After reading this chapter and attending lecture, the student should be able to: 1. Compare the two coordinating systems in animals. 2. Describe the three major functions of the nervous system. 3. List and describe the three major parts of a neuron and explain the function of each. 4. Explain how ne ...
... After reading this chapter and attending lecture, the student should be able to: 1. Compare the two coordinating systems in animals. 2. Describe the three major functions of the nervous system. 3. List and describe the three major parts of a neuron and explain the function of each. 4. Explain how ne ...
The peripheral nerves
... Type A fibers carry sensory information to the CNS concerning position, balance, and delicate touch and pressure sensations from the surface of the skin. The motor neurons that control skeletal muscles also send their commands over large, myelinated Type A axons. Type B fibers and Type C fibers carr ...
... Type A fibers carry sensory information to the CNS concerning position, balance, and delicate touch and pressure sensations from the surface of the skin. The motor neurons that control skeletal muscles also send their commands over large, myelinated Type A axons. Type B fibers and Type C fibers carr ...
BIOL 273 Midterm #1 Notes
... takes for the Na gates to get to their original “starting positions”, from where they can open again and let more Na into the cell ...
... takes for the Na gates to get to their original “starting positions”, from where they can open again and let more Na into the cell ...
577
... 6) Neurotransmitters bond to receptor sites on the post-synaptic membrane 7) Step (6) causes the Na+ gates to open on post synaptic membrane which starts the nerve impulse along that cell 8) Synaptic cleft is returned to normal - enzymes that destroy specific neurotransmitters - Ca2+ returned to th ...
... 6) Neurotransmitters bond to receptor sites on the post-synaptic membrane 7) Step (6) causes the Na+ gates to open on post synaptic membrane which starts the nerve impulse along that cell 8) Synaptic cleft is returned to normal - enzymes that destroy specific neurotransmitters - Ca2+ returned to th ...
Action potential
In physiology, an action potential is a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls, following a consistent trajectory. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and endocrine cells, as well as in some plant cells. In neurons, they play a central role in cell-to-cell communication. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events leading to contraction. In beta cells of the pancreas, they provoke release of insulin. Action potentials in neurons are also known as ""nerve impulses"" or ""spikes"", and the temporal sequence of action potentials generated by a neuron is called its ""spike train"". A neuron that emits an action potential is often said to ""fire"".Action potentials are generated by special types of voltage-gated ion channels embedded in a cell's plasma membrane. These channels are shut when the membrane potential is near the resting potential of the cell, but they rapidly begin to open if the membrane potential increases to a precisely defined threshold value. When the channels open (in response to depolarization in transmembrane voltage), they allow an inward flow of sodium ions, which changes the electrochemical gradient, which in turn produces a further rise in the membrane potential. This then causes more channels to open, producing a greater electric current across the cell membrane, and so on. The process proceeds explosively until all of the available ion channels are open, resulting in a large upswing in the membrane potential. The rapid influx of sodium ions causes the polarity of the plasma membrane to reverse, and the ion channels then rapidly inactivate. As the sodium channels close, sodium ions can no longer enter the neuron, and then they are actively transported back out of the plasma membrane. Potassium channels are then activated, and there is an outward current of potassium ions, returning the electrochemical gradient to the resting state. After an action potential has occurred, there is a transient negative shift, called the afterhyperpolarization or refractory period, due to additional potassium currents. This mechanism prevents an action potential from traveling back the way it just came.In animal cells, there are two primary types of action potentials. One type is generated by voltage-gated sodium channels, the other by voltage-gated calcium channels. Sodium-based action potentials usually last for under one millisecond, whereas calcium-based action potentials may last for 100 milliseconds or longer. In some types of neurons, slow calcium spikes provide the driving force for a long burst of rapidly emitted sodium spikes. In cardiac muscle cells, on the other hand, an initial fast sodium spike provides a ""primer"" to provoke the rapid onset of a calcium spike, which then produces muscle contraction.