Exam 2

Question 1

Quantitative risk assessment…

Answer 1

ascertains the quality of the available experimental data

Question 2

What is the highest prioritized US EPA default for data selection in hazard identification and dose response?

Answer 2

Select human data over animal data

Question 3

True or False. Asthma is characterized by open airways and easy gas exchange

Answer 3

False

Question 4

In the conducting airway, what are the anatomic structures that induce protective effects?

Answer 4

Mucus
Cilia
Mucous layer

Question 5

What is cancer characterized by?

Answer 5

• Uncontrolled cell growth and cell metastasis

- Mutations and aberrant gene expression

Question 6

Steps of Multistage Carcinogenesis

Answer 6

Initiation -> promotion-> progression

DNA damage -> proliferation -> proliferation

Question 7

What is the multi-stepped process of cells in cancer?

Answer 7

Normal -> hyperplasia -> mild dysplasia -> carcinoma in situ -> cancer (invasive)

Question 8

What are the two types of genotoxic carcinogens?

Answer 8

Direct-acting

Indirect-acting

Question 9

What are some characteristics of direct-acting carcinogens?

Answer 9

• don’t require metabolic activity
• highly electrophilic
• interact with macromolecules
• ultimate carcinogens
• test positive in Ames Test
• cause tumors at site of exposure
• detoxification pathways can inactivate

Question 10

What are some characteristics of indirect-acting carcinogens?

Answer 10

• require metabolic activity
• metabolites are highly electrophilic
• interact with macromolecules
• ultimate carcinogen
• cause tumors at target tissue site
• detoxification pathways can inactivate

Question 11

What are the difference DNA repair pathways?

Answer 11

1. direct reversal of DNA damage
2. excision repair, base excision repair, nucleotide repair, or mismatch repair
3. postreplicational repair (recombination repair)
4. nonhomologous end-jointing, double strand break repair

Question 12

What acts as the accelerator in cells?

Answer 12

proto-oncogenes

Question 13

What acts as the brake in cells?

Answer 13

tumor suppressors

Question 14

What do 90% of all human cancers have dysregulating?

Answer 14

p53

Question 15

What is the BBB extremely sensitive to?

Answer 15

oxygen and glucose

Question 16

What are the energy requirements of the BBB?

Answer 16

highly dependent on aerobic metabolism

Question 17

What are the differences between systemic capillaries and brain capillaries?

Answer 17

Systemic- fenestration and abundant pinocytosis

Brain- tight junction and lack pinocytosis

Question 18

What are the three components of axonal transport?

Answer 18

Fast axonal transport
Intermediate axonal transport
Slow component

Question 19

What is axonopathy?

Answer 19

axon degenerates while neuronal cell body continues to survive

Question 20

What is Wallerian degeneration?

Answer 20

degeneration of distal nerve stump

Question 21

How is myelin formed?

Answer 21

CNS- oligodendrocytes

PNS- Schwann cells

Question 22

What are the four targets of neurotoxicity?

Answer 22

neuron, axon, myelinating cell, neurotransmitter system

Question 23

Can axons regenerate?

Answer 23

CNS- no

PNS- yes

Question 24

Can myelin regenerate?

Answer 24

CNS- very limited

PNS- Schwann cells capable of remyelinating the axon

Question 25

What enhances dopaminergic neurotransmission?

Answer 25

cocaine

Question 26

What do nasal passages function as?

Answer 26

filters for larger particles

Question 27

Where does gas exchange take place?

Answer 27

alveoli

Question 28

What do type 1 and 2 alveolar cells do?

Answer 28

1- cover large SA | 2- produce surfactant, mitotic division into type 1

Question 29

What cells contain a high content of xenobiotic-metabolizing enzymes?

Answer 29

clara cells

Question 30

What is bronchoconstriction triggered by?

Answer 30

irritants, drugs, peptides

Question 31

What is fibrosis?

Answer 31

increased amounts of collagen that causes lung stiffness

Question 32

What are some blood-borne agents that cause pulmonary toxicity in humans?

Answer 32

``` paraquat monocrotaline bleomycin cyclophosphamide cationic amphophilic drugs ```

Question 33

What are methods for studying injury of respiratory systems?

Answer 33

- Inhalation exposure systems - Pulmonary function studies - morphologic techniques - pulmonary lavage - in vitro approaches

Question 34

What are biomarkers?

Answer 34

biological indicators of exposure or effects detected in body fluids and other tissues -provide info relative to internal exposure and disease

Question 35

What are the types of biomarkers?

Answer 35

- parent agent - biotransformed parent agent (metabolite) - increased/decreased endogenous levels of biochemicals - altered biochemical/cellular component/ cell

Question 36

What is the allergy mechanism?

Answer 36

Hapten + tissue protein = complete antigen --> sensitized t-lymphocytes

Question 37

What are examples of biomarkers of response?

Answer 37

- decreased cells - elevated liver enzymes - increased release of biochemical

Question 38

What are some factors that influence intensity of response?

Answer 38

- duration and rate of entry - concentration and dose - mode and route of exposure - acute vs. chronic - age and state of health - dose-response - env. variables - genetics