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Flashcards in Ch. 14 Deck (38)
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1
Q

Why don’t chicken have teeth?

A

They have the genes require to produce the proteins to produce teeth, but they do not activate those genes
- In this case, a change in developmental cues, alters which genes are expressed in the ‘dental issue’

2
Q

What is the importance of gene regulation? (3)

A

1) Allows multicellular organisms to have differentiated cell types
2) Allows organisms to grow until they reach a particular size
3) Allows organisms to acclimate to changes in their environment

3
Q

How do cells adapt to their environment?
Lactose in the E.coli cell
4 steps

A

1) Lactose becomes available in the environment of the bacterium
2) Due to gene regulation, the bacterium produces more Lactose permease (proteins) and B-galactosidase
3) The bacterium readily uses the lactose until it is gone
4) Most proteins involved with lactose use are degraded

4
Q

What is able to break down lactose in the cell?

A

B-galactosidase

little green things

5
Q

What transports lactose into the cell?

A

Lactose permease

Transport protein

6
Q

Cells need to alter the amounts of ________ to survive in changing environments

A

Specific proteins

7
Q

In bacteria, at which level is the altering of the amount of specific proteins done at?

A

Transcription

8
Q

Increased Transcription = _______________= ____________

A

Increased Transcription = Increased Translation = Increased Protein

9
Q

Which phase does a gene change into mRNA?

A

Transcription

10
Q

Which phase does mRNA change into a protein?

A

Translation

11
Q

Which phase does the protein change into a functional protein? Eukaryotes!!

A

Post-translation

12
Q

_________ is critical in the development of multicellular

A

Gene regulation

13
Q

During human development what is needed at different stages?

A

During human development, different hemoglobins are required at different stages

14
Q

The correct _____ must be turned on and off at the correct times

A

genes

15
Q

Which type of cell has more layers of regulation? What are they?

A

Eukaryotes

1) Transcription
2) Processing of mRNAs
3) Translation
4) Post translation

16
Q

Eukaryote:

Transcriptional regulation

A

Determines which genes are transcribed

  • Regulation of transcription
  • Chromatin remodeling to make genes accessible for transcription
17
Q

Eukaryote:

Posttrancriptional regulation

A

Determines types and availability of mRNAs to ribosomes

  • Variations in pre-mRNA processing
  • Removal of masking proteins
  • Variations in rate of mRNA breakdown
  • RNA interference
18
Q

Eukaryote:

Translational regulation

A

Determines the rate at which proteins are made

- Variations in rate of initiation of protein synthesis

19
Q

Eukaryote:

Posttranslational regulation

A

Determines the availability of finished proteins

  • Variations in rate of protein processing
  • Removal of masking segments
  • Variations in rate of protein breakdown
20
Q

What is a chicken-a-saurus?

A

A chicken with teeth, finger, and a tail

21
Q

T or F

It doesn’t matter where the proteins are made

A

False;

We need the right proteins made in the right amounts at the right time, in the right place

22
Q

What do changes in the sequence of DNA molecules do?

A

They may alter the production or function of a particular protein

23
Q

How can mutations be seen?

A

Mutations can be seen as generating a new allele for a given gene even if it does not cause a change in phenotype

24
Q

Small changes in the DNA sequence can cause ___ differences in __________

A

Big differences in protein sequence

25
Q

What can larger changes in the DNA sequence cause?

A

Larger changes in the DNA sequence cause the removal of entire genes or even the addition of new genes

26
Q

What are the 5 types of consequences of point mutations within the coding sequence of a structural gene?

A

Mutation in the DNA; Effect on polypeptide

1) None; None
2) Base substitution; SILENT- causes no change
3) Base substitution; MISSENSE - changes one amino acid
4) Base substitution; NONSENSE- changes to a stop codon
5) Addition (or deletion) of a single base; FRAMESHIFT- produces a different amino acid sequence

27
Q

Mutations can alter phenotypes by what? (4)

A

1) Generating a non-functional protein
2) Changing how a protein works
3) Altering when a gene is expressed
4) Changing where a gene is expressed

28
Q

One __________ in the hemoglobin gene causes sickle-cell anaemia

A

One base difference

29
Q

The T to A mutation in the sickle-cell disease example changes what?

A

Changes an amino acid in the protein from Glutamate to Valine
- From a hydrophilic to a hydrophobic amino acid

30
Q

Pleiotropic

A

When one base change causes a number of phenotypic changes

31
Q

In Whippet dogs, what can a mutation do?

A

A mutation in the Myostation Gene leads to increased muscle mass

32
Q

What does a 2 base deletion pair cause in the Myostatin gene?

A

Introduces and early stop codon

33
Q

Mutations

A
  • In nature, mutations are random occurences

- They can range from simple base pair changes to loss of chromosome fragments

34
Q

Mutations can be caused by ___________________

A

any agents that damage DNA & random mistakes of the DNA replication process
- EX. UV light- too much sun = certain chemical viruses

35
Q

Which type of mutations will more likely be passed on?

A

Mutations that help an organism compete will be more likely to be passed on to the next generation than mutations that are not helpful

36
Q

_______ favours evolution

Mutations are/ are not always bad

A

Strong selective pressure favours evolution

Mutations are not always bad

37
Q

Malaria

A

A debilitating disease cause by trypanosome Plasmodium falciparum which is transferred to humans via bites from the mosquito Anopheles gambiae

38
Q

The blood cells of individuals with sickle-cell disease are less able to support the Plasmodium parasite, so what is the advantage?

A

So they do not get as sick from Malaria
So the disease allele provides a competitive advantage to individuals in certain environments
Especially in heterozygous form