Science Flashcards
(143 cards)
1
Q
What is current?
A
Flow of electrical charge (one loop).
2
Q
What is diffusion?
A
Movement of particles from high concentration to low concentration.
3
Q
What is the charge of a proton?
A
Positive
4
Q
What is the charge of an electron?
A
Negative
5
Q
Name of a circuit with only one loop
A
Series circuit
6
Q
Which type of blood vessels has valves?
A
Veins, arteries
7
Q
How are the roots of a plant adapted?
A
Large surface area
8
Q
What does compound mean?
A
2 or more elements chemically combined
9
Q
What does atomic number shows?
A
The number of Protons.
10
Q
What does photosynthesis mean?
A
Process which plants use sunlight, water and carbon dioxide to create oxygen and energy in the form of sugar.
11
Q
What does mass number tells us?
A
Total number of protons and neutrons.
12
Q
What does population mean?
A
Number of individuals of the same species living in the same area at the same time.
13
Q
What does community mean?
A
Small group of people who all live in the same area, near to one another.
14
Q
What does ecosystem mean?
A
Interaction between a community and non living parts of the environment
15
Q
What are Abiotic factors?
A
Non living Environment Factors
16
Q
3 Examples of abiotic factors.
A
Temperature, light intensity and moisture levels.
17
Q
What is a Biotic factor
A
Living factor
18
Q
3 Examples of Biotic factors.
A
Predators, disease and food availability.
19
Q
What is interdependence?
A
Organisms depend on each other for survival.
20
Q
Two examples of things species depend on each other for.
A
Food and shelter.
21
Q
What is a Stable Community?
A
Populations of organisms relatively stay the same.
22
Q
Define Biomass
A
Mass of a living organisms.
23
Q
What are producers?
A
Organisms that can make their own food
24
Q
What are Isotopes?
A
Atoms of the same element with the same number of protons but different number of neutrons
25
What are the 4 levels of organisation within an ecosystem? (smallest to largest)
Organism, population, community and ecosystem.
26
What are the 2 types of cells?
Plant and Animal.
27
What are cells?
Cells are the smaller units of life and the building blocks for all organisms.
28
What are eukaryotic cells?
Complex cells that contain a nucleus and other membrane - bound organelles.
29
What are prokaryotic cells?
Simple cells that has no nucleus and other membrane - bound organelles.
30
2 Examples of Eukaryotic cells
Plant and animal cells.
31
What is a unicellular organism?
Living thing that is just one cell.
32
What is a multicellular organism?
Made of lots of cells (not just one cell).
33
What are organelles?
Small organ-like that you can find in a cell.
34
Name the organelles found in an Animal cell?
Cytoplasm, nucleus, mitochondria, ribosomes and cell membrane.
35
Function of Nucleus?
Controls cell activities and contains DNA
36
Function of Cytoplasm?
Jelly-like substance where chemical reactions occur.
37
What does Osmosis mean?
The movement of water molecules from high con
38
Function of Chloroplast?
Absorbs light energy for photosynthesis.
39
Function of Mitochondria?
Energy is released for respiration.
40
Function of DNA Loop?
Carries genetic information.
41
Function of Cell membrane?
Controls what goes in and out of the cell.
42
Function of Vacuole?
Storage organelles for water.
43
Function of Cell Wall?
Strengths the cell and gives a structure to the cell.
44
Function of Plasmid?
Small ring of Dna which codes for specific functions.
45
Function of Ribosomes?
Protein Synthesis.
46
What is an ion?
Atom with a charge.
47
How are the organization of life is ordered as following from the smallest to largest.
cells, tissues, organs, organ systems, organism.
48
What is an exothermic reaction?
Heat energy is released to the surroundings.
49
What is endothermic reaction?
Absorb energy from the surroundings.
49
What is sensitivity?
Reacting to your surroundings.
50
What is potential energy?
Stored Energy.
51
What is the Activation Energy?
Minimum amount of Energy needed for a reaction to take place.
52
What is combustion?
Combustion is another name for burning.
53
Define Element?
One type of atom only.
54
What does the pH of a solution tell you?
How acidic or alkaline it is.
55
Give an example of a physical change.
Melting chocolate
56
The carbon cycle is made up of four processes, what are they?
Photosynthesis, combustion, respiration and decomposition.
57
Put the following in order, starting with the smallest: tissue, organism, organs, organ systems, cells
cells, tissues, organ, organ systems, organism
58
State the unit of force.
Newtons
59
What are balanced forces?
Forces of the same size in opposite directions.
60
What is the equation to calculate speed?
Speed = Distance ÷ Time
61
What is the equation to calculate Density?
Density = Mass ÷ Volume
62
What is sublimation?
Change of state from a solid to a gas.
63
Name seven different types of renewable energy.
Wind, solar, tidal, HEP, geothermal, biogas, waves.
64
What is the equation for Magnification?
Magnification = Size of image ÷ Size of real object.
65
What is the equation for Pressure?
Pressure = Force ÷ Area (Answer in Pascals.)
66
What is Pressure?
When particles hit a surface and they create a force.
67
What is an enzyme?
Biological substance breaks down large molecules to small molecules.
68
What is a hormone?
Chemical messengers.
69
What is density?
How much matter there is in a given volume.
70
How many strands make up a DNA double helix?
2
71
Describe the structure of DNA molecule?
Polymer that is made up of 2 stands.
72
What is meant by term Genome?
All the genetic information of an organism.
73
What is Ionic Bonding?
Metal atoms bonding with non-metal atom.
74
What is digestion?
Break down of large molecules into smaller molecules.
75
Specific latent Heat?
Amount of energy needed to change 1kg of a substance from one state to another without changing its temperature.
76
Root Hair Cells?
Cells that allows the plant to absorb more water. They also allow a plant to take in the minerals it needs to survive.
77
What are chromosomes?
Chromosomes are structures found in the nucleus of most cells.
78
Name 3 specialised animal cells
Red blood cells, Sperm, eggs, nerve cells
79
What is the process by which cells specialize?
Cell differentiation
80
What is differentiation?
Differentiation is the process by which different types of cells develop their specific set of cell structures and become specialised.
81
When does differentiation occur?
This occurs as cells develop and mature
82
What happens during cell differentiation?
Changes in gene expression and cell structure.
83
What is the function of a Nerve Cell?
Carry messages all over the body very quickly.
84
How do nerve cells adapt to their function?
Nerve cells adapt to their function through their unique structure, electrical excitability, and specialised connections.
85
What is the function of the palisade cell?
Palisade cells are at the top of the leaves to maximise photosynthesis.
86
What is the function of the meristem cells?
Allows for plants to grow, repair damaged tissue and cell division
87
We need oxygen to release energy
We need oxygen to release energy
88
What is aerobic respiration?
Respiration is the presence of oxygen
89
What is anaerobic respiration?
Respiration without oxygen
90
alveoli where Gas exchange occurs
alveoli where Gas exchange occurs
91
Earth's atmosphere is 78% nitrogen, 21% oxygen, 1.0% argon, 0.04% carbon dioxide
Earth's atmosphere is 78% nitrogen, 21% oxygen, 1.0% argon, 0.04% carbon dioxide
92
Double circulatory system definition?
Blood passes through the heart twice on each loop around the body. It travels from the heart to the lungs, to the heart, to the rest of the body before returning to the heart.
93
Enzymes ?
biological catalyst that speed up reaction time
94
What is Resistance ?
The measure of how difficult it is for a flow of charge to pass through a component.
95
What is Independent
Variable ?
The variable you change in an
investigation to see how it affects the dependent variable.
96
Dependent
variable ?
Variable that you measure.
97
Control
variable
Keep the same plsss.
98
The Equation for Resistance ?
resistance (Ω ohms) = potential difference (V) ÷ current (A)
99
What is Resistance ?
Resistance is a measure of how difficult it is for the
current to flow around a circuit.
100
What is the function of the Artery ?
Carry blood away from the heart
101
What is the function of the Veins ?
Carry blood to the Heart.
102
What is the function of the Cappilary ?
Connects arteries and veins.
103
Describe the structure of the Artery ?
Thick muscular walls, small lumen, carry blood under high pressure, carry oxygenated blood (except for the pulmonary artery).
104
Describe the structure of the Cappilary ?
One cell thick to allow diffusion, Carry blood under very low pressure.
105
Describe the structure of the Vein ?
Thin walls, large lumen, carry blood under low pressure, have valves to stop flow in the wrong direction, carry deoxygenated blood (except for the pulmonary vein).
106
What is the function of the Coronary arteries ?
Carry oxygenated blood to the cardiac muscle.
107
What is the function of the Heart valves ?
Prevent blood in the heart from flowing in the wrong direction.
108
What is the function of the Plasma ? (55% of blood)
Transports CO2, hormones and waste.
109
White blood cells ( <1% of blood and part of your immune system )
Defend against pathogens
110
Red blood cells (45% of blood)
Carries Oxygen
111
Platelets (<1% of blood)
Form Blood Clots
112
How do you calculate the Charge Flow (in coulombs) ?
Q = Charge Flow (Coulombs) =
I = Current (Amps) x T = Time (seconds)
113
How do you calculate the Potential Difference ?
V = Potential Difference (V) =
I = Current (Amps) x Resistance (Ohms)
114
What is the function of the Live Wire ?
The live wire carries the alternating potential difference from the supply.
115
What is the function of the Neutral wire ?
Completes the Circuit.
116
What is the function of the Earth wire ?
The earth wire is a safety wire to stop the appliance becoming live. The earth wire is at 0 V, it only carries a current if there is a fault.
117
How do you calculate the Potential Difference ? (2)
E = Q x V
Energy transferred = Charge x Potential difference
E = Energy transferred (J)
Q = Charge (C)
V = Potential difference (V)
118
How to calculate power?
P = V x I
Power (W) =
Potential difference x Current
119
How to calculate power ? (2)
P = I² x R
Power =Current² x Resistance(Ω)
120
Xylem Tissue:
What it does: Transports water and minerals from the roots to the rest of the plant (upward only).
Direction: One-way (roots → stems → leaves).
Structure: Made of dead cells that form hollow tubes; strong walls to help support the plant.
121
Phloem tissue:
What it does: Transports food (mainly sugars made in the leaves) to all parts of the plant.
Direction: Two-way (can go up or down depending on where food is needed).
Structure: Made of living cells with companion cells helping with energy for transport.
122
Which process is used to produce drinking water from sea water?
Desalination
123
Why is producing drinking water from sea water expensive?
The process requires energy.
124
Which two processes are used to kill bacteria during the production of
drinking water?
Adding chlorine and the
Exposure to ultraviolet light
125
Water moves from the soil into the plant by _________________________.
Osmosis.
126
Mineral ions move from a low concentration in the soil to a high concentration
in the root by _________________.
Active Transport.
127
Sugars are transported from the leaves to other parts of the plant
by _____________________.
Translocation.
128
Each isotope of carbon has a different number of _______________________.
Neutrons
129
How does
carbon-14(8 neutrons) pass from plants to animals?
plants are eaten / consumed
130
Describe one way that lungs are adapted for gas exchange.
1) many alveoli
* large surface area
* short diffusion distance (from
air to blood)
131
Describe how the skin and the stomach protect the human body from pathogens
Skin
* (physical) barrier
* prevents entry of pathogens
* scabs form on wounds / cuts
Stomach
* (hydrochloric) acid
* (acid) kills pathogens
132
Name the part of a human cell where genes are found.
Nucleus
133
Name the chemical that genes are made of.
DNA
134
Give one human characteristic that is affected by
genes and the environment.
mass / weight / fitness /
strength / (type 2) diabetes
135
What happens to the average kinetic energy of gas particles when temperature increases?
It increases — particles gain more energy.
136
What happens to the average speed of gas particles when temperature increases?
It increases — particles move faster.
137
What happens to the pressure inside a container when gas is heated?
It increases — particles hit the walls more often and with more force.
138
The Equation for the Work done (Joules)
Work done = Force x Distance
139
Food Test - Sugar
Benedicts - Neg.- blue
Pos .- orange/red
140
Food Test - Starch
Iodine - Neg. - yellow
Pos. - B/B
141
Food Test - Protein
(amino acids)
Biurret - Neg. - B/B
Pos. - Purple
142
Food Test - Fats
Ethanol - Neg. - Colourless
Pos. - White
