Exam yr 10 semseter 1 Flashcards
DNA
Deoxyribonucleic acid molecule located in the nucleus of cells that contains the genetic information responsible for the development and function of an organism.
Gene
A distinct sequence of nucleotides forming part of a chromosome which is a unit of heredity that is transferred from a parent to offspring.
Chromosome
A threadlike structure of nucleic acids found in the nucleus of living cells, which carries genetic information in the form of genes.
Cell division
The division of a cell into two daughter cells with the same genetic material. May be mitosis (clone copy) or meiosis (for reproduction).
Gametes
Reproductive cells of plants and animals which are haploid because they contain only one set of chromosomes.
Zygote
Fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm).
Somatic cell
Cells of the body which do not include gametes. These are diploid because they contain two sets of chromosomes.
Phenotype
An individual's observable trait. This is determined by both their genomic makeup (genotype) and environmental factors.
Autosomes
All of the numbered chromosomes of the cell which do not include the sex chromosomes. These contain the bulk of the cell’s information required to function.
Homologous
Chromosomes which pair during replication and have the same structural features and pattern of genes.
Trisomy
Three copies of a chromosome instead of the normal pair of two eg the addition of a number 21 chromosome that results in Down syndrome within each cell. Only one copy of a particular chromosome is monosomy
Karyotype
The number and general appearance (size, shape and banding) of a set of chromosomes in a somatic cell.
Nucleotides
Compounds (DNA building blocks) containing a sugar part (deoxyribose or ribose), a phosphate part and a nitrogen-containing base that varies
Base-Pair Rule
The concept that in DNA every adenine (A) binds with a thymine (T), and every cytosine (C) binds to a guanine (G).
Triplet
A sequence of three nucletides in DNA that can code for one amino acid. For example the triplet base sequence CAA codes for the amino acid, valine
Diploid
The paired set of chromosomes within a somatic cell eg 23 prs in each body cell. Sex cells have only one copy of each chromosome in the cell and this is referred to as the haploid number
Variation
Differences of characteristics shown in individuals due to various reasons. Inheritance of this variations or phenotypes may be favourable to increase chance of survival.
Alleles
Alternative forms of a gene for a particular characteristic. Each allele is characterised by a slightly different nucleotide sequence
Homozygous
Having two identical alleles for a characteristic within the genotype
Heterozygous
Having two different alleles for a characteristic within the genotype
Periods
A period is a horizontal row of the Periodic table. A new period begins when a new electron energy level begins filling with electrons.
Groups
A group is a vertical column of the Periodic table. Groups all share the same number of valence electrons and have similar chemical properties.
Atomic number
the number of protons in the nucleus of an atom, which is characteristic of a chemical element and determines its place in the periodic table.
Relative atomic mass
Is a measure of how heavy atoms are, which is determined by the number of protons and neutrons in an atom.
Alkali metals
The metals which are found in group 1 of the periodic table. These are characterised by a very high reactivity, even in water, due to their single valence electron.
Alkaline earth metals
The metals which are found in group 2 of the periodic table. These are characterised by a high reactivity in acid and weak reactivity with water.
Halogen
Non-metal elements in group 17 of the periodic table. These are brightly coloured elements.
Nobel gasses
Non-metal elements in group 18 of the periodic table. These do not react easily and are considered inert because of their full valence shell of electrons.
Transition metal block
The block of elements in the middle of the periodic table. These substances tend to form colourful solutions when dissolved in water.
Lustre
Shine or sheen produced from reflected light.
Malleable
A property of metals where they are able to be hammered and pressed into shape without breaking or cracking.
Ductile
A property of metals where they are able to be drawn into thin wires without splitting or snapping.
Molecules
A group of atoms that are chemically bonded which form discrete, fundamental particles that can take part in chemical reactions.
Crystals
Geometrically shaped substances made up of atoms and molecules arranged in one of seven different shapes. Salts form crystal structures.
Ionic compounds
Compounds formed between a negative ion (anion) and a positive ion (cation) whose electrostatic attraction is the basis of their ionic bond.
Neutralisation
A reaction between an acid and a base which results in salt and water and a more neutral pH.
Salt
Result of a neutralisation reaction where the cation from an acid is ionically bonded to the anion of a base.
Enzymes
Biological catalysts which allow biological reactions to occur much faster and with a smaller activation energy.,
Brittle
A hard substance which resists change in shape, but small distortions in its structure cause widespread cracking.
Conductors
Allow energy to easily flow through the substance with little resistance. Energy may be in the form of electricity or heat.
Average speed
Distance travelled divided by time taken.
Velocity
A measure of rate of change in position. It has direction and magnitude.
Magnitude
The size of a scalar quantity.
Instantaneous speed
Speed at any particular instant of time.
Acceleration
A rate of change in speed.
Scalar quantity
quantity, such as distance and speed, that has a size but not a direction
Vector quantity
a quantity, such as displacement or velocity, that has size and direction.
Terminal velocity
The maximum velocity of an object as it falls through air depending on resistance factors.
Displacement
A measurement of the change in position of a moving body; a straight line connecting the start and end points is specified in terms of length and direction.
Distance
A measurement of how far apart objects are.
Radar gun
Mobile Radar units in police cars sent out by radio waves.
