Science y8 Flashcards
6Co2+6H2O=
C6H12O6+6O2
Ovary
After puberty and egg or an ovum is released from here once every 28 days
Gland
Adds Chemicals and nutrients to the semen
Connects the cervix to the outside of the body- the sperm is deposited here during sex.
Vagina
What is seed dispersal?
Seeds are carried away from the plant to avoid overcrowding and reduce competition for:
light
water
nutrients
Name one type of seed dispersal
Animal. Spread the seeds by eating them. Some plants have little hooks on them that get caught on the animal’s fur.
Is wind a type of seed dispersal?
Yes, some seeds are tiny and float in the air like dust. Others have special structures like wings and parachutes to keep them airborne longer.
Group 1
Alkali metals: they are kept in oil because of how reactive they are
Group 2
Alkali earth metals: Metals that are less reactive than group 1. They are often shiny and low density
Group 7
Halogens: React aggressively to group 1
Group 0
Noble gases: Chemically unreactive. Boiling point is below room temperature
Element
An element is a substance that is made up of ONE type of atom
An element made up of atoms is….
Made of one type of atom and the particles are the same and NOT joined up.
Elements can’t be split up into anything simpler by..
chemical methods
An element made up of molecules….
Atoms can be joined up but still are the SAME type
Molecules in a compound…
are DIFFERENT atoms JOINED up
A mixture of different elements
NOT a compound, elements AREN’T joined up
A chemical reaction involves..
two or more chemicals (called REACTANTS) combining together to form one or more new substances (called PRODUCTS)
Iron+ Sulphur=
Iron Sulphate
What is the first rule of naming compounds
- When elements combine the ending is USUALLY “Something- ide”
What is the second rule of naming compounds
When three or more DIFFERENT elements combine -one of them being oxygen- the ending is USUALLY “something- ate”
What is the third rule of naming compounds?
When 2 identical elements combine the name doesn’t change
Mixture is…
a substance which are not chemically joined up
Ceramics are..
made up of soft materials. When heated becomes hard. Hard and durable when heated. Soft and malleable at the start
Polymers are..
a long chain of molecules made from small repeating units, unreactive, solids, can be moulded, strong and hard wearing.
Composites are….
hard, tough and lightweight.
Metals are..
strong, shiny, flexible, ductile, malleable, good heat conductors, good electrical conductors, solid at room temp.
NON- metals are..
dull, good heat insulators, brittle, good electrical insulators, often gases/ liquids or solids that melt easily.
Day 1- 7 of menstrual cycle
The menstrual cycle starts with the first day of a woman’s period. It happens when the lining of the uterus comes away and exits through the woman’s vagina as blood.
Day 8-13 of menstrual cycle
FOLLICULAR PHASE: Around day 7 the blood flow stops. The lining of the uterus begins to build up again. At this time an egg starts to mature in one of the ovaries
Day 14 of menstrual cycle
Ovulation: The egg is released by an OVARY into the OVIDUCT
Day 15-28 of menstrual cycle
LUTEAL PHASE: an egg travels from your ovary through your fallopian tube and to your uterus.
Fertilisation
During fertilisation a sperm and and the ovum fuse on one of the oviducts and form a zygote.
Cell division
The process where the new cells are formed for growth, repair and replacement in the body
implantation
The attachment of a fertilisation egg to the wall of the uterus at the start of pregnancy
Petals are…
colourful to attract insects
Sepal
protects and supports the flower
Stamen
anther produces male sex cells (pollen)
Carpel
the female reproductive organ of a flower, consisting of an ovary, a stigma, and usually a style.
Style
where pollen tube grows down to the female sex cells.
Sounds are made when objects….
vibrate
Sound travels as…
waves, which are vibrating surfaces
Sound waves are reflected by…
most surfaces
Sound waves can only travel through..
solid, liquid, gas
They CANNOT travel through..
empty space
Oscilloscope is..
a machine that shows the wave shape of an electrical signal
The wave length is the distance between two….
crests.
The frequency of a wave is…
how many complete waves pass a certain point each second.
The amplitude of the wave is
the height of a wave. In sound waves this is volume
Volume
Amplitude
Frequency
Pitch
pollination
is the act of transferring pollen grains from the male anther of a flower to the female stigma
anther
produced male sex cells (pollen)
Insect pollinated plants have
bright petals, scented with nectar, moderate amount of pollen, sticky pollen grains, anthers are stiff and firmly attached inside.
wind pollination plants have
small and dull petals, no scent or nectar, large amount of pollen, smooth and light grains outside of the flower to release pollen easily, stigma outside to catch catch pollen grains easily
Balanced forces produce..
no change in movement
unbalanced forces change..
the speed and/or the direction of moving objects
What is a force?
A force is a push or a pull exerted on an object
What are contact forces?
forces that need to touch an object to act
What equipment is used to measure force?
A newton meter.
What is the unit of force
Newton (N)
What is the unit of mass
Kilograms (kg)
How can we show the forces acting on an object?
A force diagram
What is Hooke’s law
When a spring stretches, the extension of the spring is proportional to the force stretching it, provided the elastic limit of the spring is not exceeded.
Luminous sources
objects which create light
Plane mirror
smooth, flat mirror
incident ray
Light ray hitting a mirror.
angle of incidence
The angle between the normal and the ray of light hitting a mirror.
angle of reflection
The angle between the normal and the ray of light leaving a mirror.
normal
An imaginary line at right angles (perpendicular) to a mirror, where a ray of light hits the mirror.
angle of refraction
Angle between the light ray and the normal as it passes from one transparent material into another
opaque
no light can pass through
translucent
some light can pass through
transparent
all light can pass through
auditory range of a blue whale
19-36hz
refraction
is the way the direction of light changes when it passes from transparent material to another
What are the types of light waves.
ray, beam, divergent beam, convergent beam.
A physical change
does NOT involve any change in how the atoms of the element or compound are arranged. It can be easily reversed.
A chemical change
involves the rearrangement of atoms in elements and compounds to make DIFFERENT elements and compounds. It is very difficult to reverse the changes, but not impossible.
What part of an atom has a negative charge?
Electron
What part of an atom has a positive charge?
Proton
When a glass rod is rubbed by a silk cloth it becomes positively charged. Why is this?
Because the glass rod loses electrons to the silk cloth.
What is an electric field?
It is the space around around a charged object in which the object feels a force.
Suggest some components of a simple electrical circuit
Cell, Bulbs, Wires, Switches
What does an ammeter measure?
Current
What is the unit of measurement for Current?
Amps (A)
What does a Voltmeter measure?
Voltage
What is the unit of measurement for Voltage
Volts (V)
What is the definition of Current?
Current is the flow of electrons around a circuit
What is the long piece of coiled wire in an electromagnet called?
Solenoid
Photosynthesis
A chemical process by which green plants and some other organisms use sunlight to synthesize (make) glucose from carbon dioxide and water.
Water (H2O) for plants
Liquid required for photosynthesis. Absorbed through the roots
Light for plants
Energy required for photosynthesis.
Chlorophyll
Green chemical required for photosynthesis. It absorbs the light in the leaf.
Glucose (C6 H12 O6)
Substance made in the process of photosynthesis which the plants use for energy.
Starch
Glucose is stored as this.
Chloroplast
Part of the plant cell where photosynthesis takes place. Contains chlorophyll
Stomata
A tiny opening or pore that is used for gas exchange. They are mostly found on the under-surface of plant leaves.
Minerals for plants
Plants use minerals from the soil to build the complex molecules they need to survive and grow.
