Chapter 9-

Question 1

Cell to cell communication evolved from ____

Answer 1

Prokaryotes

Question 2

Examples of Bacteria communication

Answer 2

Spore formation, biofilm formation, and bioluminescence

Question 3

Signaling in bacteria is ___

Answer 3

Density dependent (Quorum Sensing)

Question 4

Components of Quorum Sensing

Answer 4

Autoinducers (from bacteria)
Upregulate gene expression (a process that involves the signals of the cell)

Question 5

What are the four categories of Signaling? (multicellular organism)

Answer 5

Autocrine
Contact-dependent
paracrine
endocrine

Question 6

Paracrine signaling

Answer 6

signaling molecule diffuses across environment to target cell (quick and short lived, local signal) involving and relying on neurotransmitters

Question 7

Autocrine signaling

Answer 7

A cell that produces ligand that targets itself
- example: cells infected with a virus already; sending signals that’ll bind to their own receptors, preventing the virus from spreading.

Question 8

Endocrine Signaling

Answer 8

Signals from cells that are meant for distance target cells in the blood stream.
- its like a highway with the cars being the signals and the blood stream being the highway

Question 9

Contact dependent signaling

Answer 9

-Surface receptors on two cells bind to each other locking them into place (ex: on the skin)
- gap junctions (channel between cells that signals can diffuse across)

Question 10

Ligand : a molecule that binds to ____

Answer 10

a receptor

Question 11

Examples of ligands (signaling molecules)

Answer 11

amino acids
lipids
proteins

Question 12

Intercellular (cell surface) receptors

Answer 12

Transmembrane proteins

Question 13

Intracellular receptors

Answer 13

inside the cytoplasm of the cell

Question 14

signal transduction

Answer 14

when the ligand bonds to the receptor and causes a change in the cell (3 step process)

Question 15

What are the three steps of signal transduction?

Answer 15

Reception: Ligand bonds to receptor
Transduction: shape change is made into a signal into the cytoplasm
Response: affect on the cell

Question 16

Protein Kinase Signaling

Answer 16

Kinases phosphorylate other proteins

Question 17

Cyclic AMP (cAMP)

Answer 17

Same function as proteins in the signaling cascade; it serves as a second messenger. Binds to activate PKA so it can phosphorylate with other proteins

Question 18

andenylyl cyclase

Answer 18

Uses ATP to catalyze cAMP

Question 19

Who discovered Nucleic Acids?

Answer 19

Friedrich Miecher

Question 20

The Frederick Griffith experiments

Answer 20

Discovered that genetic material can be transferred between live and dead bacteria

Question 21

Hershey and chase’s experiments

Answer 21

used radioactively labeled phosphorus and sulfur

Question 22

Erwin Chargaff discovered…

Answer 22

base pairing rules for DNA
- Adenine pairs with thymine
- Guanine pairs with Cytosine

Question 23

Who discovered the structure of DNA?

Answer 23

Rosalind Franklin (famous from watson and crick)

Question 24

DNA replication is ____

Answer 24

semi-conservative (two strands separate, old strand is used as a template, and new strands are created)

Question 25

what are the three stages of DNA replication in prokaryotes?

Answer 25

Initiation, elongation, and termination

Question 26

Initiation is the…

Answer 26

origin of replication
creates a replication fork