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Flashcards in Science Deck (36):

Define gene

The instructions for a particular trait


Define allele

The different forms of the one gene. Brown eyes and blue eyes are alleles of eye colour


Define Hederity

When a gene is passed from one generation to another. It is random in what traits you will inherit as it is all up to chance


Dominant trait

A trait that will always show even though another allele is present. An example is Bb, the capital letter shows the dominant trait


Recessive traits

A trait that will not show if a dominant trait is present. It will only appear if the present alleles are identical such as bb, the lower case letter represents the recessive trait



You have identical alleles (pure breeding) example bb or BB



You have dissimilar alleles (hybrid) such as Bb


Define genotype

A scientific notation of the alleles you have. E.g. bb


Define phenotype

The appearance of the alleles you have. e.g. Blue eyes


What are the 4 nitrogenous bases of DNA and which pair together

AT - Adenine and Thymine
GC - Guanine and Cytosine

At The Gold Coast


What is the back bone of DNA made up of?

sugar and phosphate also known as nucleotides


What is meiosis

The process of cell division that produces the gametes, eggs and sperm. In theis process the cells goes through 2 successive divisions.


Define Mitosis

When you regrow dead or damaged cells identical to the parent cells called daughter cells


What is the haploid number in a chromosome?

It is half of the diploid number and refers to the number of chromosomes in gametes (23)


What is the diploid number

the number of chromosomes in our body cells (46)


What is co-dominance

An organism that has both phenotypes of an allele present at the same time creating a patchy look like a tabby cat. An example is AB blood type.


What is Incomplete dominance?

When phenotypes of 2 alleles blend, much like mixing paint


What is a Penney square?

A square spilt up into quarters used to derive all possible alleles for someone by combining the parents genotypes


What is autosomal inherited

The form of inheritance that does not depend on gender so it is likely to see a mix of genders


What is sex-linked inheritance?

Is dependent on gender as the disorder is only found on the X chromosome meaning more boys are likely to get it than girls.


What is the role of the X and Y chromosomes in sex determination?

The gender of the child is dependent on the male. The mother give a single X chromosome and if the father gives a Y it is a boy but if he gives an X it is a girl. Depending on who gives which X depends on the passing down of X linked traits


What is a pedigree?

Like a family tree they show the inheritance of characteristics over a number of generations, these affected will be coloured in.


Define mutation

the changing of the structure of a gene, resulting in a varying form that may be passed from generation to generation. Mutation could include deletion, insertion or rearrangement of the chromosomes.


What are some genetic disorders(4)

Haemophilia - lack of blood clots
Cystic Fibrosis - affects lungs, pancreas and liver
Colour blindness - unable to distinguish colours
Down syndrome - presence of a third copy of chromosome pair 21


What are karyotpes?

A picture of our chromosomes created by staining cells and mounting them on slides. They are matched in size order


When does motion occur?

When an object changes it's position relative to another object or within a frame of reference


Define distance

How far an object would have to travel to move from one point to another


Define displacement

Between any two points is the straight line distance in a given direction


Define speed

Speed is the rate at which an object moves over a distance and so tells you how fast the distance was covered


Define velocity

the rate of speed at which something is moving and in which direction. The rate of change of displacement


Define acceleration

Is the measure of the rate at which something changes speed


Newton's third law

at any time we notice force acting, we should be able to to identify the pair of forces involved and what they're acting on.


Define weight

the force of gravity acting on an object and so how many Newtons it takes to hold it up


Define mass

is the amount of matter in an object that doesn't change no matter what the gravity


Define net force

Total of all the forces acting on the objects


What is Newtons 2nd law?

If the net force is 0, an object will continue with a constant velocity