Chapter 16

Question 1

Differentiation

Answer 1

Cells become specialized in structure and function

Question 2

Morphogenesis

Answer 2

Development of the form of an organism and its structures.

Question 3

Cytoplasmic determinants

Answer 3

A protein, or rna that is placed in an egg and influenced the early development by regulating the expression if genes that affect the developmental fate of cells.

Question 4

Induction

Answer 4

A group of embryonic cells influence the development of each other, usually by causing changes in gene expression.

-contact with cell surface molecules in neighbouring cells and the being of growth factors secreted by neighbours

Question 5

Determination

Answer 5

Point at which an embryonic cell is irreversibly committed to being a specific cell type.

Question 6

Apoptosis

Answer 6

Programmed cell death where cellular agents chop up the DNA and fragment the organelles and other cytoplasmic components.

Cells become multilobed “bleebing”

Responsible for webbed fingers

Question 7

Pattern formation

Answer 7

Tissues and organs are all in their characteristic places due to cytoplasmic determinants and inductive signals

Question 8

Positional information

Answer 8

Molecular cues that control pattern formation in an embryonic structure by indicating a cells location relative to the organisms body axes.

Question 9

Nurse and follicle cells

Answer 9

Support cells that supply the egg with nutrients and mRNAs

Question 10

Homeotic genes

Answer 10

Regulatory genes that control pattern formation in late embryo, larva and adult.

Question 11

Embryonic lethals

Answer 11

Mutations with phenotypes causing death at the embryonic or larval stage

Question 12

Maternal effect gene

Answer 12

A gene that, when mutant in the mother results in a mutant phenotype in the offspring, regardless of offsprings genotype

Question 13

Bicoid

Answer 13

A meter al effect gene that codes for a protein responsible for specifying the anterior end in flies.

Bicoid mRNA deposited in high concentration in anterior end and diffuse to posterior.

-embryo with two mutant bicoid ales has posterior at both ends of organism

Question 14

Morphogens

Answer 14

A substance that provides positional information on the form of a concentrated gradient along the embryonic axis.

Question 15

Maternal mRNAs determines what

Answer 15

Anterior, posterior, dorsal and ventral areas of offspring

Question 16

Does maternal mRNA continue through organisms life?

Answer 16

No, maternal mRNA stops after embryonic phase and gene expression takes over

Question 17

Stem cells

Answer 17

Unspecialized cells that can both reproduce themselves and even differentiate into many tissues.

Question 18

Totipotent

Answer 18

In plants, mature cells can dedifferentiate and then give rise to all the specialized cell types of an organism.

Question 19

Nuclear transplantation

Answer 19

Scientists replace nucleus of an egg with the nucleus of a differentiated cell

Question 20

Where can stem cells be isolated

Answer 20

Early embryos at blastula stage or blastocyst stage.

Question 21

Pluripotent

Answer 21

Capable of differentiating into many cell types

Question 22

Therapeutic cloning

Answer 22

When aim of cloning is to produce stem cells to treat disease.

Question 23

Induced pluripotent stem cells

Answer 23

Deprogrammed Cell

Question 24

Oncogenes

Proto-oncogenes

Answer 24

A gene found in viral or cellular genomes that is involved in triggering molecule events that can lead to cancer.

Code for normal cell growth and division.

Question 25

Three types of changes to proto-oncogenes to turn to oncogenes

Answer 25

Movement of DNA within genome
Amplification of a proto-oncogene
Point mutation in a control element or in proto-oncogene itself

Question 26

What happens to translocated chromosome ps that can cause cancer

Answer 26

Translocated porto-oncogene ends up near active promoter and its transcribed more.

Increases copies of proto-oncogene results in more proteins

Question 27

Tumor suppressor gene

Answer 27

Gene whose normal products inhibit cell division

Mutation of this =cancer

Question 28

Adult stem cells do…

Answer 28

Replenish specialized, no reproducing cells types

Question 29

Benign vs, Malignant

Metastasize

Answer 29

No cancer

Cancerous, continue to grow, invade surroundings and spread

Art of tumour breaks off and spreads

Question 30

What is meant by cancer is a multi step model

Answer 30

Requires 1 active oncogene and loss of several tumor suppressor genes

Means different treatments must be used