Science Flashcards
What are the two parts of the nervous system?
Central & peripheral nervous system
What’s the nervous system made up of?
Nerves
What kind of message do the nerves send?
Electric signals
What are the 3 main types of nerve cells?
Sensory, relay, motor
What is the nervous system?
Something the brain can send messages to, to control our body
What’s the order of stimulus response pathway?
Stimulus – Receptor – Control Centre – Effectors – Response
What are examples of effectors?
muscles or glands
What are the parts of nerves?
Cell body, dendrites, axon, myelin sheath
What’s the endocrine system made up of?
Made up of ducts and glands
What’s a hormone?
A chemical messenger which travels in the blood
What are glands?
An organ that produces useful substances that is needed somewhere in the body
What hormone does the pancreas produce?
Insulin & glucagon
What’s homeostasis?
A process to maintain the body temperature when there’s a sudden change in the external environment.
What’s a disorder of the endocrine system and what’s the cause?
Addison’s disease - when adrenal gland doesn’t product enough hormones
What’s a disorder of the nervous system and what’s the cause?
Multiple sclerosis - when immune system mistakenly attacks the brain and nerves
What’s 2 use of kidneys?
Get rid of waste and extra fluids, balance water and salt and remove acids
What are ways to look after kidney?
Don’t smoke, don’t drink, healthy diet, regular exercise
What’s the role of renal dialysis
To help people with kidney failure clean their blood
How does dialysis work?
Blood remove from patient – blood passes through the dialyzer – get all the waste out – blood return to patient
What are the 4 main groups of microorganisms?
Virus, bacteria, protozoan, fungi
What is the difference between infectious and non-infectious diseases?
Infectious diseases spread from person to person, non-infectious diseases can’t spread from person to person, it’s because of everyday habits or was born with it
Define disease:
When there’s something wrong with your body because of microorganisms
Define pathogen:
A harmful microorganism to your body
Examples of the 4 microorganisms:
Virus: covid-19
Bacteria: Salmonella
Protozoan: malaria
Fungi: athlete’s foot
What’s the first and second line defence?
First-line defence - barriers to keep microorganisms out of body
Second line defence – inflammation & get more phagocytes (white blood cells) to engulf foreign particles
What are parts of body that acts as barriers to diseases?
Skin – low hp, doesn’t let microorganisms get into body
Cilia – hair-like projections to get mucous/microbes out of body
Mucous membranes – trap microorganisms
Chemical – tears (enzyme – kill microorganisms)
What is some evidence of the inflammation response?
Swollen – more fluid (blood) in area, more phagocytes (white blood cell) engulf foreign particles, more heat – helps kill pathogen
(Occurs when tissues are damaged)
What’s the role of B-cell
Create antibodies, kill pathogens, remember virus so create antibodies faster next time
What’s active immunity?
Someone’s body creates their own antibodies - lasts for a long time (basically forever), memory cell is produced
What’s passive immunity?
Injections of antibodies, not created by the body - lasts for a short period so have to take multiple injections, no memory cell is produced
What’s vaccine and how does it work?
An injection that contains a weaker/dead version of the virus so your body would create antibodies and memory cells
Which way does transverse transfer?
Transverse waves move particles up and down, energy to the left
Which way does longitudinal waves transfer?
Longitudinal waves move particles left and right, energy moves to the left
Define: Wavelength
The distance between two adjacent crests or throughs on a wave
Define: Frequency
The number of vibrations that pass through a point in a second, measured in Hz
Define: Speed
How fast the wave is going in a direction
Define: Amplitude
The height of the wave
Memorise the wave equation/triangle
Search online
How is sound produced?
By the vibration of matter
(by the vibration of stuff)
Why does sound need a medium to travel?
It cannot travel without a medium as there’re no particles to make the sound wave travel
How are pitch related to frequency for sound wave?
Higher the pitch the higher the frequency, the lower the pitch the lower the frequency.
How are volume related to amplitude for sound wave?
Higher the volume the higher the amplitude, the lower the volume the lower the amplitude
Memories echo equation/triangle
Search online
What are the 7 radiation types on the electromagnetic spectrum?
- Gamma ray
- X-ray
- Ultraviolet
- Visible
- Infrared
- Microwave
- Radio
Identify key trends in frequency and wavelength and relate to energy in the EM spectrum
The shorter the wavelength, the higher the energy and the frequency
What is the law of reflection?
The angle of reflection equals to the angle of incidence (θr = θi)
Memorise concave, convex and plane mirrors
Search online
What is the process of refraction?
The bending of light as it changes direction when it travels from one medium to another