Science Flashcards
(111 cards)
1
Q
What effect does tar have on the cilia
A
It causes the cilia to stop working and eventually die
1
Q
Explain why muscles need more blood during exercise
A
Muscles require more energy during exercise. Additional oxygen and glucose are needed to release the energy. Blood flow increases to supply these to muscles faster. Respiration also increases to allow more oxygen to be transported to the muscles.
2
Q
what are dangers of being too underweight?
A
Lack of energy, poor immune system, lack of minerals and vitamins
3
Q
What are dangers of being too overweight?
A
Stroke, heart disease, type 2 diabetes, cancer
4
Q
What are carbs
A
Main source of energy in the diet
5
Q
What are proteins?
A
used for the growth and repairing of the body
6
Q
What are vitamins and minerals
A
Important for the function and development of the body example-vegetables
7
Q
What does fibre do
A
It bulks out food to keep it moving through the digestive system example-oats
8
Q
What are lipids
A
help control what goes in and out of your cells and store energy
9
Q
How do you test for starch
A
Iodine solution- turns black
10
Q
How do you test for sugar
A
Benedict’s solution- turns orange/red
11
Q
How do you test for lipids
A
Ethanol- turns cloudy
12
Q
How do you test for protein
A
Biuret solution- turns purple
13
Q
What are enzymes
A
proteins that speed up (catalyse) solutions. They are in the digestive system and break down starch into glucose
14
Q
What do digestive enzymes do
A
Break down substances into new substances without being changed in the reaction
15
Q
What chemical in tobacco makes it addictive?
A
Nicotine
16
Q
What are atoms
A
Particles far too small to see even with a microscope. Everything is made out of atoms
17
Q
What is an element?
A
A substance that is only made up of one type of atom like oxygen
18
Q
What is a compound
A
A substance that is made up of 2 or more types of elements which are chemically bonded like H20
19
Q
What is a mixture
A
A substance that is made up of 2 or more types of compounds or elements that can be physically seperated, no chemical bond
20
Q
What carries glucose from the intestine to other parts of your body
A
blood
21
Q
What is glucose?
A
A type of sugar you get from foods you eat and your body uses for energy
22
Q
What does saliva contain that causes starch to change
A
amylase enzymes
23
Q
What are the properties of a metal?
A
High melting and boiling points, good conductors, shiny, malleable, sonorous, hard and strong, high density
24
What is the structure of an atom
All atoms have a nucleus. Inside the nucleus are the protons and neutrons and in the outer shells are the electrons
25
what do horizontal rows on the periodic table tell you
called periods- tell you how many shells an element has
26
Which period is the most reactive
The last one, period 7
27
What does the group number tell you
number of electrons in the outer shell
28
What are group 7 elements also called
The halogens, they are reactive, have 7 shells in the outer shell, diatomic and non metals
29
What is the proton/atomic number
tells us the total number of electrons. found under name of the element
30
How do you draw the electronic structure of an element
. write symbol
. find the period the element is in and draw the shells
. start drawing crosses to draw electrons. 1st shell has 2
. find group the element is in to fins number of electrons in the outer shell
31
What is a force
A strength/energy as an attribute of physical action of movement. Can be a push, pull or twist. Can change an object's speed, direction or shape. Forces are measured in newtons.
32
What is upthrust
Upward force that a liquid or gas exerts on a body in floating it
33
What is friction
Force that acts between 2 surfaces that are touching. It opposes their movement and acts as an invisible brake
34
What is weight?
The mass a person weighs multiplied by the gravitational pull of an area. Measured in newtons
35
What is static energy?
imbalance of electric charges within or on the surface of a material
36
What is an electric field
physical field surrounding electrical charged particles. Created by a charged object
37
What is energy?
The flow of charged particles
38
What is current
measure of electrons flowing through a circuit. The more charge that flows, the bigger the current. Measured using an ammeter
39
What is potential difference/voltage?
The push provided by a cell or battery to make charges move. measured in volts with a voltmeter
40
what is resistance
Components do different jobs in an electric circuit. Each circuit component has a different resistance which tells you how easy/ difficult it is for the charges to pass through the component. It is measured in ohms. Affected by material of wire, how thick and long the wire is and the temperature of the wire
41
What is a magnetic field
the region around a magnetic material
42
What is a permanent magnet
A magnet that has its own magnetic field
43
What is an electromagnet
A temporary magnet that can be turned off by turning the current off. it is a soft metal core made into a magnet by the passage of electric current through a coil surrounding it. To increase the strength you can increase the number of coils, increase size of current and use materials that can be easily magnestised and demagnetised
44
what is the word equation for photosynthesis
Carbon dioxide+water ARROW glucose + oxygen
45
Where does photosynthesis occur?
In the chloroplasts in the leaf cells
46
why are leaves and stems green
the contain the green pigment chlorophyll
47
What is a solution?
A mixture in which 1 or more solutes is dissolved in a solvent
48
What is a solvent?
A substance in which something is dissolved
49
What is a solute
a substance that can be dissolved
50
What happens when sugar dissolves?
Water particles surround each sugar particle. The sugar particles can mix with the liquid. They are arranged randomly and move around
51
How do you increase the rate that a solute dissolves
stir the mixture, increase temp of solvent, crush solute
52
What is filtration used for?
Used to sepearte a liquid and an insoluble solid
53
What is evaporation used for?
Used to remove the solute from the solution. It is used when the solute dissolves in the liquid and filtration can't be used. It gets rid of the solvent
54
What is dissolving
a process where solute particles disperse throughout the solvent
55
What si energy
the potentiual to do work. it cannot be created or destroyed, only transfered betweenn differnet energy stores. It is measured in joules.
56
What are different types of energy stores?
.Kinetic energy- movement
. Gravitational potential energy- potential to fall due to gravity
. thermal energy- heat
. Elastic potential energy- stretching and compressing
57
What is temperature?
how hot or cold something is
58
What is fuel?
Materials that are burnt to produce a large amount of heat energy e.g. coal
59
What are fossil fuels?
Fuels produced naturally, not infinite, release C02, cheap, readily available
60
What do greenhouse gases do?
Trap heat in atmosphere
61
What is stationary?
An object that is not moving and has speed 0m/s
62
What is speed?
A measure of how quickly a distance is covered er unit time
63
What is the equation for speed
speed= distance/time
64
What is the thinking distance?
How far the car travels in the time it takes for the driver to press the brakes after realising they need to stop
65
What is the braking distance?
How far the car travels after the driver has applied the break
66
What is the equation for the stopping distance?
Stopping distance= thinking distance+ braking distance
67
What do crumple zones do?
Increase the time taken for the car to stop meaning that the impact force is less
68
What happens if the volume is smaller?
The pressure is higher and thereofre there are more collisions between molecules and the walls of the container
69
What happens when a gas cools down?
molecules move more slowly and the pressure decreases
70
What happens when a gas heats up?
molecules move more quickly and there are more collisions and the pressure increases
71
How does the less air pressure going down on you affect you?
The higher you go. Atomspheric pressure changes with altitude, the higher you go the lower the weight of the air above you and the lower the atmospheric pressure
72
what happens the deeper you go
the greater the weight of the pressure above and the greater the liquid pressure
73
What force is produced by liquid pressure?
Upthrust, the force that keeps things afloat. It acts on any object that is floating or submerged in a liquid
74
How can you make the gas pressure increase?
Increase temperture, decrease volume
75
How can you make the gas temperature decrease?
Decrease temperature, increase volume
76
What is atmospheric pressure?
caused by air particles colliding with a surface. As height increases there is always less air above a surface than at a lower height. Atmospheric pressure decreases as we go higher up
77
What is pressure?
A measure of how much force is applied over a certain area
78
What is the equation for pressure?
Pressure= force/ area
79
why is renewable energy good?
Doesn't run out because it is naturally plenished, environmentally friendly, safe
80
What is nuclear energy?
Energy released from the nucleus. It doesn't release crbon dioxide or sulfure dioxide and it produces a lot of energy but it is hazardous and non renewable
81
What do animals compete for?
Water, food, space, mates
82
what do plants compete for?
Minerals, water, space, light
83
What is competition?
interaction between organisms after the same limited resources
84
What are adaptations of a cactus?
. Thick waxy skin to prevent water loss
. Large fleshy stems to store water
. Spikes to prevent fleshy stem from being eaten
. Shallow widespread roots to absorb rain and nutrients/minerals
85
What is the predator prey relationship?
It shows how the population of the prey and the predator are linked. When the population of the prey is high, the population of the predators increases as they now have a larger food supply. However, if there is a large predator population, the population of the prey decreases. Now that there is less prey, the predators have a smaller food supply so their population decreases. As a result of this, the prey relationship increases again and the process repeats
86
What are structural adaptations?
Physical features that allow an organism to be succesful in its envuronment
87
What are functional adaptations?
special biological processes an organsims body might perform to make it well suited to its environment like sweating
88
What are behavioural adaptations?
Actions an organism might perform to make it well suited to its enviroment like hibernation and migration
89
What are the 4 steps in plant reproduction?
Pollination, fertilisation, seed dispersal, germination
90
What is pollination
transfer of pollen from the anther to the stigma. It can happen using wind or insects
91
What is the carpel?
Female part of the flower
92
What is the stamen
male part of the flower
93
What is the ovule
female gamete
94
What part of the flower holds the stigma
the style
95
What part of the flower catches pollen
the stigma
96
What does the anther do
produces pollen
97
What does the sepal do
special leaf that protects unopened buds
98
What happens when you rub a balloon on your jumper
electrons are transferred from the jumper to the balloon. The balloon now has an overall negative charge and the jumper has an overall positive charge. They now attract
99
How does the current change around a circuit
the current is the same everywhere in series
100
How does the p.d/voltage change around the circuit
it is the same everywhere in parallel
101
food tests, electricity, photosynthesis, anaerobic, aerobic, adaptation, variation, acids and metals, speed, distance
102
What is the word equation for photosynthesis
carbon dioxide+water ARROW glucose + oxygen
103
Where does photosynthesis take place?
In the chloroplasts in the leaf cells
104
what is photosynthesis
most plants make their own food. They do this using gas in the air and water absorbed by the roots in the soil to create sugar. Energy is needed to do this. The source of energy in photosynthesis is sunlight. The nuclear store of energy in the sun is transfered to a chemical store of energy in the plant by light. energy is transfered to the chlorophyll in the chloproplasts of the leaf cells.
105
How does water get into a plant
Water is diffused into the root hair cells and then transported around the plant in xylem tubes.
106
Why do plants have a large surface area
to absorb as much light as possible
107
How do gases get into and out of a leaf
Through tiny holes on the bottom surface of a leaf called stomata. They allow gases to diffuse in and out of a leaf. Carbon dioxide diffuses in and oxygen and water vapour diffuse out. Stomata are open and closed by guard cells. Guard cells open them in the day and close them in the night.
108
what are the 2 layers of the leaf
palisade layer- packed with chloroplasts, where most photosynthesis occurs
spongy layer- has air spaces allowing gases to diffuse in and out of the leaf
109
what minerals do plants need
magnesium, potassium, phosphates, nitrates
110
Which direction do magnetic field lines travel
from the north to south pole
