Unit 1 Science Assessment

Regions where there is a 95% probability of locating an electron. An orbital can hold a maximum of two electrons.

<p>hydrogen</p> Signup and view all the answers

<p>Sodium chloride</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>A unit of substance equivalent to the number of atoms in 12 g of carbon-12. 1 mole of a compound has a mass equal to its relative atomic mass expressed in grams.</p> Signup and view all the answers

<p>This shows the ratio between elements in a chemical compound. It is useful when discussing giant structures such a sodium chloride.</p> Signup and view all the answers

<p>The mass of one mole of water</p> Signup and view all the answers

<p>A solution of known concentration used in volumetric analysis.</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>A key characteristic of all waves, and it means the tendency of a wave to spread out in all directions, transferring energy to its surroundings as it does so.</p> Signup and view all the answers

<p>regular</p> Signup and view all the answers

<p>reflected, transmitted</p> Signup and view all the answers

<p>'Sticking together and is used to describe waves whose superposition gives a visible interference pattern. To be coherent, waves must share the same frequency and same wavelength and have a constant phase difference.'</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>A tuning fork</p> Signup and view all the answers

<p>The storing of energy in an oscillation or a stationary wave, the energy coming from an external source of appropriate frequency.</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>When the light ray comes to the other side of the glass block and tries to leave, back out into the air, or ideally into a vacuum, the light wave will speed up. That makes the wave-front turn back towards the direction in which it was travelling before it entered the glass.</p> Signup and view all the answers

<p>They are more reliable than using copper and can travel far longer distances without the need for boosters.</p> Signup and view all the answers

<p>Multimode and single mode.</p> Signup and view all the answers

<p>2.997 925 x 10^8 m/s</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>Sunlight is refracted and reflected off raindrops, and this separates different wavelengths of light.</p> Signup and view all the answers

<p>Analogue signals are where the strength of the signal is proportional to the quantity being represented, while digital signals are where a string of numbers is used, to represent the quantity being measured.</p> Signup and view all the answers

<p>This is a technique used in fibre optics to transmit many different wavelengths of light down the same fibre at the same time, with each wavelength carrying a different channel of data.</p> Signup and view all the answers

<p>Prokaryotic and eukaryotic.</p> Signup and view all the answers

<p>Specialised structures found within a living cell.</p> Signup and view all the answers

<p>It contains genetic information and controls the activities of the cell. It is the largest organelle and is surrounded by a nuclear envelope, which is made up of a double membrane.</p> Signup and view all the answers

<p>They are responsible for the final stages of cellular respiration, which releases energy for the organism.</p> Signup and view all the answers

<p>They contain hydrolytic enzymes that break down waste material inside the cell. They have a spherical shape and are surrounded by a membrane.</p> Signup and view all the answers

<p>They modify and package proteins into vesicles for use inside the cell or outside the cell. It is a stack of membrane-bound flattened sacs.</p> Signup and view all the answers

<p>It is responsible for synthesising and transporting proteins. It is a network of membrane-bound flattened sacs called cisternae.</p> Signup and view all the answers

<p>It synthesises and transports lipids and carbohydrates. It is a network of membrane-bound flattened sacs called cisternae, that do not contain protein.</p> Signup and view all the answers

<p>They are responsible for the formation of spindle fibres for cell division. They are small tubes of protein fibres.</p> Signup and view all the answers

<p>It's a strong supporting structure made of cellulose. It helps to protect the cell and keep it rigid. It also maintains turgor pressure, which is the pressure of the cell contents on the cell wall.</p> Signup and view all the answers

<p>They are the site of photosynthesis, where light energy is trapped by chlorophyll and used to produce carbohydrate molecules from water and carbon dioxide.</p> Signup and view all the answers

<p>They maintain turgor and store cell sap, which includes water and dissolved sugars that give the plant a rigid structure.</p> Signup and view all the answers

<p>They allow transport and communication between individual plant cells. They are microscopic channels that cross the cell walls of plant cells.</p> Signup and view all the answers

<p>Skeletal, smooth and cardiac.</p> Signup and view all the answers

<p>It contracts in order to move the walls of hollow organs, such as the stomach and bladder. It is also not under voluntary control.</p> Signup and view all the answers

<p>It contracts in order to make the heartbeat. It is found only in the heart. This means that is not under voluntary control.</p> Signup and view all the answers

<p>They receive and facilitate nerve impulses, or action potentials. They consist of a large cell body, a soma with small projections called dendrites and an axon.</p> Signup and view all the answers

<p>This is a small gap between the end of one neuron and the dendrite of the following neuron. This is where nerve impulses travel from one neuron to the next.</p> Signup and view all the answers

<p>Resting potential is the potential when the nerve is not transmitting, while an action potential is the potential difference created across the membrane when the nerve is conducting an impulse.</p> Signup and view all the answers