UNIT 3.1

Question 1

DNA

Answer 1

genetic blueprint which codes and determines the characteristics of an origin
Packed and organized into structures called chromosomes

Question 2

Genes

Answer 2

A heritable factor that consists of a specific length of DNA and that encodes for a specific trait

Question 3

Recessive Gene

Answer 3

Allele that is not expressed in the heterozygous genotype(minority)

Question 4

Dominant Gene

Answer 4

Allele that is expressed in the heterozygous genotype (majority)

Question 5

Genome

Answer 5

Consists of the entire genetic material of an organism

Question 6

Chromosomes

Answer 6

Long DNA molecules which contain many genes
Eukaryotes stored in the nucleus
Prokaryotes circular found form

Question 7

Diploid

Answer 7

A pair of each kind of chromosome

Question 8

Haploid

Answer 8

One copy of each chromosome

Question 9

Histone

Answer 9

a type of protein found in a chromosome

Question 10

Locus

Answer 10

The position of a gene on a particular chromosome

Question 11

Alleles

Answer 11

An alternative form of a gene that code for different variations of a specific trait (occupies the same locus as other alleles of the same gene)

Question 12

Homozygous

Answer 12

two copies of the same allele

Question 13

Heterozygous

Answer 13

two different alleles

Question 14

Genome Vs. Proteome

Genome
Same Nucleus:
Non-coding sequences:
Human Genomes

Proteome

Answer 14

Genome: specific number for the total genetic information

INFO:
Chloroplast and mitochondria have their own nucleus
Includes non-coding DNA sequence: introns, promoters, short tandem repeats)

Human Genomes:
46 chromosomes
3 billion base pairs
21,000 genes

Proteome: specific number for the total proteins a species has

Question 15

Human Genome Project (HGP)

Outcomes (4):

Answer 15

The Human Genome Project (HGP) was an international cooperative venture established to sequence the human genome
* The HGP showed that humans share the majority of their sequence, with short nucleotide polymorphisms contributing to diversity

Completion of the Human Genome Project in 2003

1) Mapping – The number, location, size and sequence of human genes is now established

2) Screening – This has allowed for the production of specific gene probes to detect sufferers and carriers of genetic diseases

3) Medicine – The discovery of new proteins has led to improved treatments (pharmacogenetics and rational drug design)

4) Ancestry – Comparisons with other genomes have provided insight into the origins, evolution and migratory patterns of man

Question 16

Gene Comparison
Escherichia Coli (bacteria):
Gallus gallus (chicken):
Homo Sapiens:
Daphnia pulex (water flea):
Oryza sativa: (arroz)
*Check Good Notes for Diagram

Answer 16

Escherichia Coli (bacteria): 4200
Gallus gallus (chicken): 17,000
Homo Sapiens: 21,000
Daphnia pulex (water flea): 31,000
Oryza sativa: (arroz): 38,000

Question 17

Base pairings
Homo Sapiens:
T2 Phage:
Canopu Plant:
Escherichia Coli
Fruit Fly:

Answer 17

Homo Sapiens: 3.2
T2 Phage: 164,000
Canopu Plant: 150,000
Escherichia Coli: 4.6 billion
Fruit Fly: 130 billion

Question 18

Mutations

What is formed?
Beneficial:
Detrimental:
Neutral:

Answer 18

Gene mutation: A permanent change in the nucleotide sequence of a sanction of DNA coding for a specific trait

New alleles are formed by mutation
They can be beneficial, detrimental or neutral:

Beneficial mutation (missense): create new variations of a trait

Detrimental mutations (nonsense): abrogate the normal function of a trait

Neutral mutations (silent): no effect on the functioning of a feature

Question 19

Sickle Cell Anemia
*Check Good Notes for Diagram

Answer 19

Disease allele arose from a base substitution mutation: a single base was changed in the gene sequence

Produces abnormal red blood cells

Question 20

Sickle Cell Anemia: Causes
*Check Good Notes for Diagram

Answer 20

Results from a change to the 6th codon for the beta chain of haemoglobin

DNA: Template strand: CTC → CAC

mRNA : GAG → GUG in the 6th codon position

Polypeptide: The sixth amino acid for the beta chain of haemoglobin is changed from glutamic acid to valine (Glu → Val)

Question 21

Sickle Cell Anemia: Consequences (2)
*Check Good Notes for Diagram

Answer 21

Consequences of Sickle Cell Anaemia
- Amino acid from glutamic acid to valine (Glu → Val)
- Glutamic acid: polar
- Valine: non-polar → causes it to form insoluble fibrous strands
- Instead of normal globular haemoglobin → clumped fibrous haemoglobin

Formation of fibrous haemoglobin changes the shape of the red blood cell → sickle shape
* May form clots within the capillaries → blocks the blood supply to vital organs + causes myriad health issues
* Destroys more rapidly than normal cells → Low red blood cell count → anaemia → Constant fatigue

Question 22

Sickle Cell Anemia with Malaria

Carried by who:
People with this:
*Check Good Notes for Diagram

Answer 22

Parasitic disease caused by plasmodium cell
*Carried by the Anopheles mosquito and invades normal red blood cells causing them to lyse (disintegrate)

*People with sickle cell disease are resistant to sickle cell disease
*Sickle cell is more prevalent where malaria is endemic (local)