10sc4.23

what is the basic structure of dna

The basic structure of DNA is a double helix made up of nucleotides. Each nucleotide consists of a sugar (deoxyribose), a phosphate group, and a nitrogenous base The two strands are held together by hydrogen bonds between the complementary base pairs (A-T and G-C).

what are the four nitrogenouse bases

adenine, thymine, guanine, cytosine

how do the nitrogenous pairs bond

adenine and thymine, guanine and cytosine

what is a complimentary sequence

A sequence that pairs with another sequence in a way that every nucleotide in one sequence is matched with its complimentary base in the other sequence.

what is a template strand

the dna sequence that needs its complimentary sequence

whats the basic structure of a nucleotide

The basic structure of a nucleotide consists of a phosphate group, a sugar molecule (ribose or deoxyribose), and a nitrogenous base

what did ediqn changraft discover in 1950

that there is an equal amount of a’s and t’s, and an equal amount of c’s and g’s, however he did not understand the basic dna structure

what did rosalind franklin produce x-ray diffraction pictures of

dna molecules, which gave important clues to dna’s structure

who hypothesised the double helix shape and how

watson and crick, they were shown rosalind franklins photo and hypothesised the shape.

what types of cells use mitosis

Cells that undergo mitosis are somatic cells, which make up the majority of our body tissues. They are responsible for growth, repair, and maintenance. Mitosis is the process of cell division in which two identical daughter cells are produced, each containing the same number of chromosomes as the parent cell.

what types of cells use meiosis

Cells that use meiosis are reproductive cells, also known as gametes. They include sperm cells in males and egg cells in females.

what does the acronym PMAT stand for

prophase, metaphase, anaphase, telophase

what happens in prophase

chromosomes coil up, nuclear envelope disappears, spindle fibres form

what happens in metaphase

chromosomes line up in middle of cell, spindle fibres connect to chromosomes

what happens in anaphase

chromosome copies divide, spindle fibres pull chromosomes to opposite poles.

what happens in telophase

chromosomes uncoil, nuclear envelopes form, spindle fibres disappear, 2 new nuclei are formed.

when does interphase happen and what happens in it

happens in the time between the cells dividing, cells spend most time in this part, just a cell chilling out doing cell things

what are female and male gametes and what happens when the female gamete is fertilised by the male?

female gamete is the egg, male gamete is the sperm, when the female gamete is fertilised, it becomes a zygote, with half the chromosomes from the father, and half from the mother.

what is a mutation?

an error in dna replication, after the dna has been unzipped by an enzyme, then it replicates itself, if an error is made, it is a mutation

whats a mutagen?

a factor that causes mutations

whats the difference between a gene and an allel?

Gene refers to a segment of DNA that codes for a specific trait, while an allele is a variant form of a gene. Genes exist in pairs on homologous chromosomes, while alleles can be different versions of the same gene. Alleles contribute to genetic diversity within a population.

whats the difference between genotype and phenotype?

Genotype refers to an organism's genetic makeup or the combination of alleles it carries for a particular trait. Phenotype, on the other hand, is the physical expression or observable characteristics resulting from the interaction between genotype and the environment.

whats the difference between heterozygous and homozygous?

Heterozygous: Having two different alleles for a specific gene.

Homozygous: Having two identical alleles for a specific gene.

whats the difference between dominant and recessive genes?

Dominant genes are expressed when present, overpowering recessive genes. Recessive genes are only expressed when paired with another recessive gene.

what is test crossing?

Test crossing is a breeding technique that involves crossing an individual with a known genotype with an individual with an unknown genotype to determine the unknown genotype.

whats an ionic compound?

A type of chemical compound formed by the electrostatic attraction between positively and negatively charged ions. They have high melting and boiling points, and conduct electricity when dissolved in water or melted.

what are cations and anions?

Cations are positively charged ions formed by losing electrons, while anions are negatively charged ions formed by gaining electrons.

what are covalent compounds?

Chemical compounds formed by the sharing of electrons between atoms, creating strong bonds. They typically occur between nonmetals and are characterized by their low melting and boiling points.

whats an acid?

A substance with a sour taste and the ability to dissolve metals and burn skin.

It releases hydrogen ions (H+) in water and has a pH below 7.

whats a base?

A base is a substance that accepts or reacts with protons, donates electrons, and has a pH greater than 7. It neutralizes acids and forms salts.

whats a salt?

substance produced by the reaction of an acid with a base, it consists of a positive ion of a base and a negative ion of an acid

what is neutralization and what is its chemical word equation?

a chemical reaction where a acid and a base react together to produce a salt and water

acid + base → salt + water

how do acids react with metal and what is the chemical word equation?

acids reacting with reactive metals make a salt and hydrogen

acid + metal → salt + hydrogen

how do acids react with carbonates and what is the chemical word equation?

acids reacting with carbonate produce a salt, water, and carbon dioxide

acid + carbonate → salt + water + carbon dioxide

how do acids react with metal carbonates and what is the chemical word equation?

acids reacting with metal carbonate produce salt, water, and carbon dioxide which fizzes off as gas.

acid + metal carbonate → salt + water + carbon dioxide

how can you test for carbon dioxide?

through the limewater test, when carbon dioxide is bubbled through limewater, it turns a cloudy or milky colour.

what is corrosion and what is its chemical word equation?

when a metal reacts with oxygen, it forms a metal oxide. salt and heat can speed up this process

what is decomposition and what is its chemical word equation?

chemical reaction that occurs when a substance is broken down into at least two other substances.

eg iron carbonate → iron oxide + carbon dioxide

what is electrolysis?

the process where substances are broken down into simpler substances when an electric current is passed through them

what is precipitation and what is the chemical word equation for it?

reactions that produce a solid from the mixing of two solutions

AB + CD → AD + CB

which sulfates are insoluble?

lead sulfate and barium sulfate

which chlorines, bromides, and iodides are insoluble?

lead and silver

which carbonates are soluble?

sodium, potassium, ammonium

what is the chemical word equation for cellular respiration?

glucose + oxygen → carbon dioxide + water

what is the chemical word equation for photosynthesis?

carbon dioxide + water → glucose + oxygen

what is digestion?

breaking up of food into smaller molecules that can be absorbed and used by the body.

what is an endothermic reaction?

a chemical reaction that absorbs thermal energy in order to make or break chemical bonds between atoms

what is an exothermic reaction?

a chemical reaction that creates thermal energy, which comes from the chemical energy stored in the bonds between the atoms of the reactants, when the bonds break, energy is released.

whats the difference between respiration and combustion?

combustion is a reaction where the substance reacts with oxygen and heat is released, the energy is released in a single step, respiration is organic compounds releasing energy, energy released in stepwise manner

how does increasing temperature affect chemical reactions?

increases the kinetic energy of the molecules and particles, which increases the frequency of particle collisions, therefore increases chance of successful collisions

how does increasing surface area affect chemical reactions?

increases the number of particles that are exposed and available to react, increases the frequency of particle collisions, which increases rate of reaction

how does increasing concentration affect chemical reactions?

increases rate of reaction as there are a greater number of particles to react, which increases frequency of collisions

how does using a catalyst affect chemical reactions?

provides an alternate route for the reaction with a lower activation energy, molecules require less energy in order for a reaction to occur, increasing the rate of reaction.

what is net force?

the sum of all forces acting on an object

what is inertia?

an objects tendency to continue moving

what is the equation for force?

Force = acceleration * mass

what is the equation for distance?

distance = speed * time

what is the equation for acceleration?

(final speed - initial speed) / time

what is newtons first law of motion?

A body at rest will remain at rest and a body in motion will remain in motion unless acted on by another force.

what is newtons second law of motion?

a force acting on an object is equal to the mass of that object times its acceleration (F=ma)

what is newtons third law of motion?

for every action, there is an equal and opposite reaction.