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Flashcards in Science Deck (36)
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0
Q

Define allele

A

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

1
Q

Define gene

A

The instructions for a particular trait

2
Q

Define Hederity

A

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

3
Q

Dominant trait

A

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

4
Q

Recessive traits

A

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

5
Q

Homozygous

A

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

6
Q

Hetrozygous

A

You have dissimilar alleles (hybrid) such as Bb

7
Q

Define genotype

A

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

8
Q

Define phenotype

A

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

9
Q

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

A

AT - Adenine and Thymine
GC - Guanine and Cytosine

At The Gold Coast

10
Q

What is the back bone of DNA made up of?

A

sugar and phosphate also known as nucleotides

11
Q

What is meiosis

A

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

12
Q

Define Mitosis

A

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

13
Q

What is the haploid number in a chromosome?

A

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

14
Q

What is the diploid number

A

the number of chromosomes in our body cells (46)

15
Q

What is co-dominance

A

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.

16
Q

What is Incomplete dominance?

A

When phenotypes of 2 alleles blend, much like mixing paint

17
Q

What is a Penney square?

A

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

18
Q

What is autosomal inherited

A

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

19
Q

What is sex-linked inheritance?

A

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

20
Q

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

A

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

21
Q

What is a pedigree?

A

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

22
Q

Define mutation

A

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.

23
Q

What are some genetic disorders(4)

A

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

24
Q

What are karyotpes?

A

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

25
Q

When does motion occur?

A

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

26
Q

Define distance

A

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

27
Q

Define displacement

A

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

28
Q

Define speed

A

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

29
Q

Define velocity

A

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

30
Q

Define acceleration

A

Is the measure of the rate at which something changes speed

31
Q

Newton’s third law

A

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.

32
Q

Define weight

A

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

33
Q

Define mass

A

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

34
Q

Define net force

A

Total of all the forces acting on the objects

35
Q

What is Newtons 2nd law?

A

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