IB Biology- Neurons & Synapses and Immune System - Human Body Systems

This flashcard set is made based off of what needs to be learned for the Neuron & Synapse and the Immune System unit of human body system topic.

Action Potential

rapid sequence of changes in voltage across a neuron

Threshold potential

the voltage (mV) required to create action potential

Threshold potential Voltage

-55 (mV)

Resting Potential

occurs when the neuron is not firing, net negative charge inside neuron, actively maintained by sodium potassium pump

Resting Potential Voltage

-70 mv

Depolarazation

sodium channels open and N+ goes in

Depolarazation Voltage

+30 mV

Repolorazation

potassium channels open and potassium rushes out

Repolarazation Voltage

-80 mV

Refractory Period

resets neuron to resting potential, potassium and sodium channels close and sodium potassium pump opens

Myelin Impact

increases speed of impulse conduction by allowing the electrical signal to skip Schwann cells to nodes of Ranvier

Neurotransmitters

released in response to the depolorazation of a axon terminal of a presynaptic neuron, these can inhibit (prevent) or excite (trigger) a response

Pathogen

disease causing agent that disrupts the normal activity of it’s host

Antigen

the specific molecules on the outside of a cell which mark it as itself

antibody

molecules which are produced to tag antigen cells and increase a phagocyte response, usually produced by the body

innate immune system

the part of your immune system that doesn’t adapt this includes (fever, inflammation, ect) This part of the immune system is good for fast reactions to pathogens and enhances adaptive immune system

adaptive immune system

consists of phagocytes, lymphocytes (B Cells) and helper T Cells, adapts to specific pathogens and therefore can more easily deal with pathogens.

HIV

targets helper t cell then undergoes a phase of latency where it replicates next it kills a lot of helper t cells leading to a inability to respond to other pathogens

Skin

maintains antimicrobial enzymes to discourage bacteria grown, secretes oils to lower pH, provide protection from outside environment, thick and dry barrier of mostly dead cells

Mucous Membrane

coasts inside of body, provide protection internally, maintain thin living layer of cells which secrete enzymes like lysosome which breaks down cell walls.

Phagocytes

white blood cell; conducts pseudopodia (engulfing cell) and is called by enzymes released by damaged tissues

B Lymphocytes (B Cell)

part of the specific response, this cell can produce antibody against and recognize a particular pathogenic antigens

Helper T Cell

regulatory cells which release cytokines to activate B cells

Virus Structure

nucleic acid surrounded by a shell, don’t have metabolic activities and so are unaffected by antibiotics

Primary Immune response

the first time a pathogen is encountered

Macrophages

eliminate non- selectively

Dendritic Cells

eliminate no-selectively, present antigens of pathogens to Helper t cell

Secondary Immune response

the second time that a person comes into contact with a pathogen

Memory T Cell

recognizes previous antigen and triggers memory b cells

Memory B cell

recognizes antigen given by memory t cell, produces antibodies, and begins to divide rapidly into short lived cells which produce more antibodies

Clonal cells

short lived B cell clones that produce numerous antibodies

Pathogenesis

the creation of a new pathogen

Zoonotic disease transmission

happens when a disease jumps from one species to another, can happen when eating or interacting with infected animals, often is the cause of the most deadly diseases