scienece Flashcards
1st levels of organisation
a tissue is a group of similar cells that work together to perform a similar function
2nd layer of organisation
an organ is made up of a group of different tissues that work together to perform a similar function
3rd layer of organisation
an organ system is a group of different organs that work together to perform a similar function
last layer of organisation
a multicellular organism is made up of several organ systems working together to form all the processes needed to stay alive
what is gas exchange
when you breathe in oxygen and breathe out co2 which takes place in lungs
RESPIRATORY SYSTEM
air enters through mouth & nose
it moves down the trachea (windpipe)
it moves down a bronchus (smaller tube)
moves through a bronchihole (tiny tube)
moves through an alveoluc (air sac)
oxygen then diffuses into blood
what happens in our body when we inhale
muscles between ribs contract -pulls ribcage up and down
diaphragm contracts - moves down
volume inside chest increases
pressure inside chest decreases
what happens in out body when we exhale
muscles between ribs relax- pulls ribcage down and in
diaphragm relaxes -moves up
voleume inside chest decreases
pressur inside chest increases
what is a bone
living tissue in a blood supply
functions of a skeleton
supports the body
protects vital oragnisms
helps the body move
makes blood cells
what is a joint
its where 2 or more bones join together
hinge joint
backwards and forwards movement
ball-and-socket-joint
all direction
what is a muscle
a type of tissue which work together to cause movement they can only pull
fixed joints
no movement
to bend arm vs straighten arm
b
biceps contract
triceps relax
s
biceps relax
triceps contract
what is photosynthesis
plants making food through the process of photosynthesis
the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar
word equation for photosynthesis
carbon dioxide + water → glucose + oxygen
where does photosynthesis take place
mainly in chloroplasts in the leaf cells
how does water get into a plant?
water diffuses into the roothair cells which is then transported around the plant in xylem tubes
how do gases get in & out of a plant
on the underside of the leaf there are tiny holes (stomata) which allow gases to dissuse into the leaf. c02 diffususes into the leaf & h2o diffuse out of the leaf
minerals plants need
nitrates - healthy growth
phosphates - healthy roots
potassium -healthy leaves & flowers
magensium - making chlorophyll
whats mineral deficiency
when a plant doesn’t grow enough minerals
what is aerobic respiration
glucose reacting with oxygen in a chemical reaction
aerobic respiration word equation
glucose + oxygen → carbon dioxide + water + energy
what is anaerobic respiration
respiration thet doesn’t use oxygen
food chain
a diagram that shows what an organism eats
food web
a set of linked food chains which show the feeding relationships of organisms more easily
eco-system
plants & animals that are found in a particular location
metals and non metals side on periodic table
metals- right
non-metals - left
properties of a metal
good conductor of heat & electricity
soorous
shiny
high density
high melting point
malleable and ductile
non metals
poor conductor of electricity and heat
not sonorous
brittle
low boiling point
low density dull
groups and periods
groups - vertical columns
periods- horizontal rows
elements of group 1
good conducter of electricity and heat
shiny when freshly cut
very reactive
reactions get more vigorous from top to bottom
alkali metals
melting pointdecreases from top to bottom
elements of group 7
low melting points
called hallogens
dont conduct electricity
brittle solid
melting point increaes from top to bottom
reeactions get less vigorous down the group
element of group 0
called noble gases
low melting & boiling points
unreactive
noble gases get slightly more reacitve from top to bottom
acids and metals
some metals react with hydrochloric acid & the products are
how to canculate average speed
to calculate average speed, you divide the tota distance by the total time taken
what is an element
an element is a substance which cannot be broken down into other sybtances
what is an atom
smallest part of an element that can exist all the atoms of an element are thr same as eachother
what is a compound
A substance made up of atoms of 2 or more elements
what is a mollecule
a jroup of 2 or more atoms strongly joined together
acids & alkalis
acids taste sour
alkali are more soapy
what is the pH scale
The pH scale measures how acidic an object is. The scale has values ranging from zero (the most acidic) to 14 (the most basic)
what is a wave (sound)
an oscillation or vibration that transfers energy. The distance from the centre to the top of the wave. The distance from one crest to the next crest is the wavelength
sound and energy transfer
sound is produced by objects that vibrate. This makes the air molecules move backwards and forwards a soundwave
where does sound travel fastest & slwoest
sound travels fastest in liquids and slowest in air. Sound cannot travel in empty spaces
loudness & pitch
the loudnes of a sound depends on the amplitude and the pitch of the sound depends on the frequency ( measured in hertz)
eye & the cornea
when you look at an apple the light is reflected off on the apple and into your pupil. The cornea and the lens focus the light on to the retina. The light forms an inverted image
how do we hear?
your eardrum vibrates and passes the vibration on to the ossicles. They are tiny bones that amplify the sound, which then make the oval window vibrate. This then passes the vibration on to the liquid of the cochlea. Specialised cells at the base of the hairs convert the movement to an electric signal which travels down the auditory nerve to your brain
