CMI Mold Biology & Ecology

Question 1

What is the primary reproductive structure of mold that allows it to spread through the air?

Accepted Answer

Spores

Answer

Mold reproduces by releasing spores, which are microscopic particles that travel through the air and colonize new surfaces when conditions of moisture, temperature, and nutrients are favorable.

Question 2

Which of the following best describes the vegetative body of a mold fungus?

Accepted Answer

Mycelium

Answer

The mycelium is the vegetative part of a fungus, consisting of a network of branching thread-like structures called hyphae that absorb nutrients from the substrate.

Question 3

At approximately what minimum relative humidity do most common indoor molds begin to grow?

Accepted Answer

60%

Answer

Most common indoor molds begin to grow when relative humidity exceeds approximately 60%, which is why building scientists recommend keeping indoor RH below this threshold.

Question 4

Which fungal genus is commonly called 'black mold' and requires chronically wet, cellulose-rich materials to grow?

Accepted Answer

Stachybotrys

Answer

Stachybotrys chartarum is commonly called 'black mold' and requires consistently saturated cellulose-rich materials such as drywall paper or ceiling tiles, making it a marker of chronic water intrusion.

Question 5

What is the term for the individual thread-like filaments that collectively form the body of a mold?

Accepted Answer

Hyphae

Answer

Hyphae are the individual microscopic filaments that, when massed together, form the mycelium — the main structural and nutritive body of a mold fungus.

(CMI) Certified Mold Inspector Practice Test

(CMI) Certified Mold Inspector Practice Test

CMI Mold Biology & Ecology