Excretory, immune and nervous systems
Carolina Elias 8B
Nervous System
Excretory System
Immune System
Body's defense against any disease/ invaders
1st line of defense: skin
Epidermis:
Forms a protection surface
Releases substances that kill attackers
Cilia and mucus
When you breathe in, you also inhale bacterias, mucus try to block it, so it stays stuck.
Cilia, moves the mucus to the throat for coughing or swallowing.
Saliva
Helps to “kill” bacteria with its chemicals.
Stomach Acid
A strong acid produced in the stomach eliminates bacterias that are swallowed
2nd Line of defense
White Blood Cells
When enemies enters in the body, white blood cell start working on the defense.
Usually the circulate in the blood, but they need to act on the tissues if any invader is detected.
Phagocytes and Macrophages:
They eat external particles and break them into lysosomes
T-cells:
Identify infected cells and kill them
Search for more cells to kill
Inflammatory Response
When cells are affected, they release histamines
example: capillaries dilate
Interferon
Give viruses the ability of attack other viruses.
3rd Line of Defense
Antibodies
Infections rarely make it until here
Cause release of antibodies
Production
WBCs collect mean particles and break them up
Show them to T-cells, that identifies the pieces and find certain B-cells to produce antibodies
Immunity:
Resistance to harmful substances.
Active:
You produce the defense
Vaccine:
You insert an ideal amount of antigens, and then your body develops immunity
Duration
Each antigen has an specific duration
Passive
You don't produce it
You receive from your mother when she is pregnant
Allergies:
Immune disorder
Your body identifies external items as harmful things.
Main way of communication and control in your body
Sends and receives message
Peripheral Nerves, brain and spinal cord
Cerebrum
PNS:
Sensory: gets informations and send it to CNS.
Motor: sends information from CNS to muscles, organs, etc.
Somatic- voluntary
Autonomic- involuntary:
Sympathetic: stress reactions
Interneurons: connect different neurons with the brain and spinal cord.
Nerve Cells
Transports informations through electrochemical process
Nucleus
Dendrite: receives message
Cell body: contain nucleus and organelles
Axon: transfer information away from the cell body
Myelin Sheath: accelerates transmissions
Node Of Ranvier: membrane between schwann cells
Schwann cell: supporting cells of PNS
Axon terminal
Synapse:
Gap between nerve and cells
Neurotransmitters transmit the information through synapse.
Reflex:
Responds to stimulus without immediately brain interference.
Message is transmitted to the spinal cord.
Frontal lobe: reasoning, planning, movement emotions,solving problems
Parietal lobe: touch, pressure, temperature, pain.
Temporal lobe: hear, memory
Occipital lobe: vision
Cerebellum: sense of balance and voluntary muscles
Pons and medulla oblongata: Breathing, heart rate, blood pressure, swallowing and digestion
Parasympathetic: relaxation reactions
Excretion
Wastes that are produced by your body
Elimination:
Wastes that are not produced by your body
Organs:
Lungs:inhale CO², exhale H²O
Skin: sweat (excretes salt, urea and H²O)
Large Intestine: rests of foods are turns into solid and are eliminated. Mucus that is formed inside the large intestine is excreted with the waste eliminated.
Liver: nitrogen to urea, changes poisonous substances to be removed from our body, hemoglobin to bile
Urinary System
Organs:
Kidney: filters blood (removes urea, removes water and salts, regulates blood pressure, volume and pH)
Ureter: urine passes through it to go to the bladder.
Bladder: stores urine
Urethra: connects bladder with the outside, removes urine from the body.
Nephrons: filters inside the kidney
Formation:
Filtration
Reabsorption
Concentration
Secretion
Ureter: urine passes through it to go to the bladder.
Relations
Excretory and immune system: the excretory system removes bad substances from our body, some of them, substances that the immune system “killed”.
Nervous and excretory: You control when you pee, with the help of the nervous system.
Immune and nervous: They are related because of the secretion of hormones