Chapter 3- Genetics- Theoretical Genetics

Question 0

Define phenotype

Answer 0

Characteristics of traits of an organisms

Eg: five fingers, colour blindness and type O blood

Question 1

Define genotype

Answer 1

Symbolic representation of a pair of alleles possessed by an organism
eg: Bb GG tt

Question 2

Define dominant allele

Answer 2

Always expressed when its present it cannot be masked by a normal allele

Question 3

Define recessive allele

Answer 3

Can be masked by another allele- only expressed when 2 copies are present

Question 4

Define co dominant allele

Answer 4

Pairs of alleles that both have affect on the phenotype when present on a heterozygous

Question 5

Define locus

Answer 5

Particular position on homologous chromosomes of a gene. Each gene is found on a specific pair of chromosomes

Question 6

Define homozygous

Answer 6

Having 2 identical alleles of a gene

Eg: AA

Question 7

Define heterozygous

Answer 7

Having 2 different alleles of a gene

Eg: Aa

Question 8

Define carrier

Answer 8

An individual that has one copy of a recessive allele that causes a genetic disease in individuals that are homozygous for this alleles

Question 9

Define test cross

Answer 9

Testing a suspected heterozygous by crosses it with a homozygous recessive

Question 10

Do a diagram of a punnet grid

Answer 10

Martha.

Question 11

What is an example of genes that have more that 2 alleles?

Answer 11

ABO blood group system in humans

Question 12

How does the ABO work as 3 alleles?

Answer 12

Share co-dominance (can be expressed equally in phenotype) and share incomplete dominance (neither fully expressed phenotype=blending)

Question 13

What do ABO blood types demonstrate ?

Answer 13

A dominance order (allele A > allele B > allele C)

Question 14

What are the four possible phenotype types for ABO blood groups?

Answer 14

A, B, AB and O

Question 15

How to ABO create these 4 blood types?

Answer 15

There are 3 alleles of the gene and these alleles can produce 6 different genotypes

Question 16

What is the gene for ABO blood type represented as?

Answer 16

Letter I

Question 17

What is the allele for type A blood group?

Answer 17

I^A

Question 18

What is the allele for type B blood group?

Answer 18

I ^ B

Question 19

What is the allele for type O

Answer 19

ii

Question 20

Crossing over of the ABO gives how many possibilities?

Answer 20

6

Question 21

What does I^A I^A or I^A i give?

Answer 21

Gives phenotype blood group A

Question 22

What does I^B I^B or I^B i give?

Answer 22

Blood group B

Question 23

What does I^A I^B give?

Answer 23

Type AB

Question 24

What does ii give in blood groups?

Answer 24

Blood group O

Question 25

Antigen A has what type of antibodies? | And what type of blood can't it have/have?

Answer 25

Anti-B antibodies and can't have B or AB blood but can have O or A blood

Question 26

Antigen B what type of antibodies does it have? And what type of blood can it have/can't have

Answer 26

Has anti-A antibodies and can't have A or AB blood but can have B or O blood

Question 27

What type of antibodies does antigen AB have? And type of blood can it have/can't have

Answer 27

Doesn't have any antibodies but can have any blood type- it is the universal recipient

Question 28

What types of antibodies has A and B?and what types of blood can it only have?

Answer 28

Has both A and B antibodies and can only have O blood- is the universal donor

Question 29

How many pairs of chromosomes do humans have?

Answer 29

23

Question 30

What are the first 22 chromosomes known as?

Answer 30

Autosomes- each chromosome pairs possess the same genes and structural features

Question 31

What is the 23rd chromosome responsible for and known as?

Answer 31

Heterosomes (sex chromosome) and determines gender

Question 32

What is the father always responsible for?

Answer 32

Determining gender

Question 33

If male sperm contains X chromosome the embryo will defiently be?

Answer 33

A girl

Question 34

There is always a 50\50% chance on what? Also draw the grid to prove it

Answer 34

That is will be a boy or a girl

Question 35

A Y chromate is different in size to an X chromosome how?

Answer 35

It is much smaller and only contains a few genes- has fewer loci

Question 36

On males where are the majority of alleles present? And what does this impact?

Answer 36

On the X chromosome and have no alleles to pair with on the smaller Y chromosome

Question 37

Define sex linkage

Answer 37

Any genetic trait whose allele has its locus on the X chromosome is sex linked

Question 38

What are colour blindness and haemophilia both examples of?

Answer 38

X-linked recessive condiitions

Question 39

Where is the gene loci found for colour blindness/haemophilia on the X chromosome?

Answer 39

On the non-homologous region of the X chromosome (not present in Y chromosome)

Question 40

Why can't males carry the gene for colour blind embeds and haemophilia?

Answer 40

As males only have one allele for this gene they cannot carry it for the condition

Question 41

As males can't carry the gene for haemophilia and colour blindness what does this mean they have a higher frequency of?

Answer 41

Higher frequency of being recessive and expressing trait

Question 42

Where do males inherit X linked recessive conditions from?

Answer 42

The mother

Question 43

Where do females inherit sex linked conditions from?

Answer 43

Females only inherit an X linked condition if they receive a recessive gene from both parents

Question 44

What is the genotype for affect and unaffected haemophilia?

Answer 44

X^H= unaffected X^h=affected

Question 45

What is the genotype for affected and unaffected colour blindness

Answer 45

X^A=unaffected X^a=affected

Question 46

Draw a punnet grid to show how males and females inherit colour blindness and haemophilia

Answer 46

Fucking do it

Question 47

Why can females be homozygous or heterozygous with respect to sex linked genes?

Answer 47

As human females have 2 X chromosomes (and therefore 2 alleles for any give X-linked gene) they can be either homozygous or heterozygous

Question 48

Why can men only be hemizygous?

Answer 48

Only have 1 X chromosome (therefore only 1 allele)

Question 49

Why can females be carriers for X linked recessive conditions?

Answer 49

Because they have 2 chromosomes-- males X Y can't

Question 50

So why does a male have a greater chance of getting a sex linked condition?

Answer 50

Cuz a male only inherits an X chromosome from his mother not his father.

Question 51

Draw a punnet grid to show autosomal dominance/recessive

Answer 51

Jf kana

Question 52

Draw a punnet grid to show co dominance

Question 53

Draw a punnet grid to show x-linked recessive

Question 54

On a pedigree chart what represents an unaffected female and an affected female

Answer 54

Unaffected- white circle | Affected- black circle

Question 55

On a pedigree chart what represents an Unaffected male and an affected male?

Answer 55

``` Affected= black square Unaffected= white square ```

Question 56

All affected individuals must have at what on a pedigree chart?

Answer 56

At least one affected parent

Question 57

If 2 parents are unaffected on a pedigree chart what are the offspring?

Answer 57

All must be unaffected

Question 58

If 2 parents are affected on a pedigree chart what are the offspring?

Answer 58

May have offspring who are affected if parents are heterozygous

Question 59

Draw a diagram of a pedigree chart with a dominant allele as parents

Answer 59

Baka

Question 60

Draw a pedigree chart with a recessive allele as parents

Answer 60

Kahslanipasbbshdsk