Science test body systems Flashcards
What are the requirements of living things?
MRS.GREN = Movement, respiration, growth, reproduction, excretion, nutrition
What classifies something as “living”?
If it follows MRS.GREN
Name all the parts of the heart
4 chambers: two upper atria (atriums), two lower ventricles and 4 valves
Describe the roles of the 4 valves
- Aorta = main artery 2. Pulmonary = another artery 3/4. Mitral and tricuspid = main veins carry blood to heart
What is the role of veins? What are they?
Veins are blood vessels in the body that carry oxygen-poor blood and pump in back to the heart (to be then pumped to the lungs to be re-oxygenated)
What is the role of arteries? What are they?
Arteries are blood vessels that transport oxygen-rich blood away from the heart to deliver oxygen around the body
What is the role of capillaries? What are they?
Capillaries are small blood vessels that branch around the body (particularly in smaller areas such as fingertips or toes) to deliver oxygen and nutrients
What is the role of oxygen in the body?
The base of all survival - necessary for respiration, nutrition etc
Why does the body need to get rid of CO2?
Whilst in small amounts it is harmless, large amounts of CO2 present in the body is toxic and can cause major harm.
Describe the journey of air as it travels down the respiratory system.
Inhale oxygen, travels through the pharynx (back of the throat) to the larynx (voice box) , down the trachea/windpipe and to the bronchi. The air travels down the bronchi into bronchioles, which go to the alveoli for gas exchange. Carbon dioxide is then breathed out.
What are bronchi?
The large air passages in the lungs
What are bronchioles?
Smaller pathways in the lungs that branch from bronchi
What are alveoli?
Tiny air sacs at the end of bronchioles where gas exchange takes place
What is gas exchange?
The process in the alveoli where CO2 in blood is exchanged with oxygen. This exchange happens with every inhalation and exhalation.
What is the trachea?
WIndpipe, airway for oxygen to voice box
What is the epiglottis?
A flap in the throat that prevents food and objects from entering the trachea (and lungs)
What is the larynx?
Stores the vocal cords, and voice box, above the esophagus and trachea.
what is the pharynx?
The hollow tube inside the neck that starts behind the nose and ends at the top of the trachea (windpipe) and esophagu
What is the pathway of the exretory system?
‘Used’ blood which has picked up waste travels to the kidneys. The waste moves through the ureters to the bladder where it is stored. The urine is released through the urethra.
On average, how much can the bladder store?
About 600ml
What is the urethra?
The organ in which urine exits the body.
What do kidneys do?
Cleanse the blood of waste
What is the ureter?
@ long tubes acting as pathways from the kidney to the bladder
What is the function of the bladder?
Stores urine until release
How does the kidneys react to dehydration?
They can send excess water back through the body rather than giving it to the bladder
Where does the blood go once it’s been cleaned?
The filtered blood leaves the kidneys through the renal vein, moves up the inferior vena cava, and goes back to the heart
What is urine made from?
Waste products, water, and urea
Where is the peripheral nervous system located?
Outside the spinal cord and brain. For example arms, legs, etc
Where is the central nervous system located?
In the spinal cord and brain
Function of the motor neuron
Sends an electrical response to parts of the body to cause a voluntary or involuntary response to a stimuli
The function of the sensory neuron
Converting reactions to stimuli into an electrical signal
What is the reflex response pathway? (decision making)
The stimulus is acknowledged by the receptor. This passes through the peripheral system via the sensory neuron to the brain where a response is sent through the motor neurons to initiate a response.
What is the reflex response pathway? (automatic)
stimulus —> receptor —> sensory nerve —> spinal cord (spinal reflex arc) —> motor neuron —> effector (thing that does response) —> response
What is homeostasis?
The state of hormonal/chemical/internal balance in a living thing
In what ways can the body maintain its body temperature?
Sweating times of heat, goosebumps/shivering when cold
What is a cell membrane (neuron)?
Where processes are triggered
What is the myelin sheath (neuron)?
Fatty layer surrounding the axon to protect cell and speed up signal
What is the axon?
Part of nerve cell where electrical signal travels down
What are dendrites?
Where nerve received signals
What are axon endings?
Where nerve cell connects synapse to another cell.
Where does the right side of the heart pump to?
The lungs
Where does the left side of the heart pump to?
The body
Where does the left side of the heart pump to?
The body
What side of the heart is stronger? Why?
Left = pumps to body = more area to pump to
