Module 4 Genes in Development

Question 1

The success of process of development is due to the ____ of different genes.

Answer 1

Timed functioning

There is a schedule for when genes are turned on and turned off

Question 2

DIFFERENTIAL Gene expression: 3 Postulates of Differential Gene Expression

EVERY ___ contains the ___ established in the fertilized egg. DNAs of ALL differentiated cells are identical.

The ____ in differentiated cells are NOT DESTROYED NOR MUTATED, they RETAIN the potential for being ___

Only a ___ of the GENOME is expressed in each cell, and a PORTION of the RNA synthesized in the cell is SPECIFIC for that cell type

Answer 2

Cell Nucleus, Complete genome

Unused genes, Expressed

Small Percentage

Question 3

The process by which an INDIVIDUAL CELL acquires a specialized function

It requires a change in the PATTERN of the GENE EXPRESSION in a cell

Answer 3

Differentiation

Question 4

Contains everything a cell needs for it to develop into any kind of cell (TOTIPOTENT)

Answer 4

Zygote / Fertilized Egg

Question 5

True or False: Pluripotent cells can transform into all types of cells like totipotent cells

Answer 5

False, they can only become MANY types of cells

Question 6

What stage do cells become tissue-specific?

Answer 6

After blastocyst stage (Proliferation : Mitiotic Divisions)

Question 7

SELECTIVE increase in the number of copies of a gene coding for a specififc coding without increase in other genes

Answer 7

Gene amplification

Question 8

Proof of gene amplification: (3)

Answer 8

Polytene Chromosomes

Lampbrush chromosomes

Reticulocytes

Question 9

Giant chromosomes:

POLYTENE Chromosomes in the ___ of the ___ ~2000 um

They are produced through ___

They DO NOT UNDERGO MITOSIS

Answer 9

Salivary glands of the fruit fly Drosophila

Endoreplication

Question 10

Giant Chromosomes:

LAMPBRUSH chromosomes in the ___(germ cells in the ovary) of AMPHIBIANS and insects; extremely large SYNAPSED homologous chromosomes which can be seen in the ___ stage og MEIOTIC PROPHASE 1 ~1500 to 2000 um

Answer 10

oocytes

diplotene

Question 11

Reticulocytes can be found where?

Answer 11

Immature Red Blood Cells WITHOUT NUCLEI

Question 12

Parts of a Polytene chromosome (4)

Answer 12

Dark bands (Chromomeres)

Light baands ( Chromonemata)

Question 13

Formed in POLYTENE chromosomes which are REVERSIBLE and addociated with DIFFERENTIAL GENE ACTIVATION

Answer 13

Chromosome Puffs

Balbiani Rings

Question 14

LAMPBRUSH CHROMOSOME PARTS (3)

Answer 14

Axis - chromomeres, interchromomere region

Lateral loops - have TRANSCRIPTIONALLY ACTIVE DNA for yolk