Chapter 14

Question 1

What are the three types of gross(big) mutations

Answer 1

1 change in total number of chromosomes
2 change in part of a chromosomes
3 change in arrangement of chromosomes

Question 2

Two names of the changes in total number of chromosomes due to non disjunction in meiosis

Answer 2

Monosmy- one chromosome missing

Trisomy- one extra chromosome

Question 3

Two names for change in part of a chromosome

Answer 3

Duplication- part of chromosome is duplicated but there’s still 46 in total (chromosome longer)
Deletion- part of chromosome is missing but there’s still 46 (chromosome shorter)

Question 4

Name of Change in arrangement of chromosomes

Answer 4

Translation- when part of one chromosome joins another chromosome

Question 5

What does (47, +21) mean

Answer 5

47 chromosomes in total

An extra chromosome 21

Question 6

What kind of genetic material is not available from karyotype analysis

Answer 6

Point mutations(small mutation)
When a base is missing/ single base change

Question 7

What kind of information that karyotype provides about an individual

Answer 7

Displays if there is any types of gross mutation which cause defects- total number of chromosome
- sex determination

Question 8

Define karyotype

Answer 8

Chromosomes present in a cell arranged in an organised manner

Question 9

Define autosomal

Answer 9

Non sex determining Genes eg eye colour

Question 10

In humans and Birds which are homogametic and heterogametic

Answer 10

Homogametic- females (XX)
Heterogametic- males (XY)

Birds are opposite
Female (ZW)
Male (ZZ)

Question 11

Define codiminance and incomplete dominance

Answer 11

Co-dominance - the two phenotype share shown eg black and white spots
Incomplete dominance- blend between phenotype eg red and white makes pink

Question 12

What does the circle and square stand for in pedigrees

Answer 12

Circle - female

Square - males

Question 13

What is Environmental Sex determination and example

Answer 13

The sex of offspring depends on the incubation temp of the eggs
Eg happens in reptiles(turtles)

Question 14

What does phenotype and environment=phenotype mean? And example

Answer 14

The environment can influence how genes are expressed eg environment factors include diet, temperature

Siamese cats are sensitive to temperature and in low temperatures enzymes convert the extremities of the cat(nose ears paws) to the dark colour

Question 15

What is FISH

Answer 15

A type of fluorescent staining used to identify specific chromosomes and makes it easier to find their pair

Question 16

Define homologous and nonhomologous

Answer 16

Homologous- the members of each matching pair of chromosomes eg the two number 5 chromosomes. They have the same length and gene loci

Nonhomologous- nonmatching chromosomes eg number 5 chromosome and number 14 chromosome

Question 17

What is the general trend of genes on a chromosome

Answer 17

The smaller the length the less amount of genes HOWEVER there are a few exemptions for unknown reasons

Question 18

What does Klinefelter syndrome show

Answer 18

(XX Y) extra whole chromosome

Question 19

What does a female with Turner syndrome

Answer 19

(X0) only in females missing X chromosome

Question 20

Down syndrome

Answer 20

Extra chromosome 21 (+21)

Question 21

Limitations of data obtained from the human genome project

Answer 21

Social stigma/ discrimination

Who owns this information(argument)

Question 22

Other then the nucleus, name two other locations DNA might be found in plant/animal cell

Answer 22

Mitrocondria- DNA that codes for proteins needed in cellular respiration
Chloroplasts- DNA that codes for proteins needed in photosynthesis

Question 23

Where is DNA found in prokaryotes

Answer 23

Circular DNA which is free floating in the cytosol

Question 24

How is DNA packaged into chromosomes

Answer 24

The negative phosphate groups of DNA is attracted to the positive histone proteins. DNA winds around the hinstones to form nucleosomes. Nucleosomes super coil to form chromosomes

Question 25

Define epigenetics

Answer 25

Literally means above genetics. Factors other than DNA sequence, such as hinstones and methylation modification that effect expressions of genes

Question 26

What are the two factors of epigenetics and explain them

Answer 26

Methyl group- off switches that turn off gene expressions when bound to DNA

Hinstones- loosely bound DNA=expressed more frequently
-tightly bound DNA= expressed less frequently

Question 27

What is polygenes and example and formula

Answer 27

Multiple genes contribute to a factor eg skin colour ++ ++ means darkest colour – – lightest

Formula =2n+1

Question 28

Define monogenic

Answer 28

Refers to traits that are under control of single genes with two alleles

Question 29

Define polygenetic inheritance

Answer 29

Trait affected by many genes eg weight, height, skin colour (found on more then one chromosome)

Question 30

How to tell if a pedigree is X linked dominant or recessive OR Y linked

Answer 30

Count numbers of boys and girls
More females = dominant X linked
More males = recessive X linked
Only males = Y linked

Question 31

What kind of disease in Huntingtons disease

Answer 31

Autosomal dominant

Question 32

What type of disease is cystic fibrosis

Answer 32

Autosomal recessive