Respiratory System

Question 1

Early in embryonic development, ____ _____ invaginate to form ____ ____.

Answer 1

nasal placodes; nasal pits

Question 2

The medial nasal processes merge to form the ______ _____ which will develop into the future ________, _____ & ____ _____.

Answer 2

intermaxillary process; bridge of the nose, philtrum & primary palate

Question 3

Failure of the fusion of the ______ and _____ result in a cleft lip.

Answer 3

lateral edges of the intermaxillary process and maxillary prominence

Question 4

Step 1 of nasal cavity development:

1. The _____ membrane regresses to connect the ectodermally lined line _____ to the endodermally lined _______

Answer 4

oropharyngeal (buccopharyngeal) membrane;
stomodeum; pharynx/foregut

Question 5

Step 2 of nasal cavity development:

2. The nasal pits expand to form a ___ ___ ____, which is initially separated from the primary oral cavity by the ______ membrane; the caudal aspect of this subsequently regresses to form a common nasal and oral cavity (i.e., primary choanae)

Answer 5

primary nasal cavity; oronasal membrane

Question 6

Step 3 of nasal cavity development:

3. Then the primary palate (-ie remaining cranial portion of the oronasal membrane) and the palatal shelves elongate to from a _____ _____ that separates the nasal and oral cavities.

Answer 6

complete palate

Question 7

The cranial portion of the foregut (ie, endoderm just caudal to the pharynx) develops an evagination called the ___ ___, which is the primordium of the lungs.

Answer 7

lung bud (respiratory diverticulum)

Question 8

the lung bud becomes the developing ____ and ___ __ which quickly grows in a ____ direction and bifurcates into the left and right primary bronchial buds.

Answer 8

larynx and primitive trachea; caudal direction

Question 9

bronchial buds continue to grow and bifurcate; and branch into _____ and _____ ______

Answer 9

terminal and respiratory bronchioles

Question 10

During late gestation, respiratory bronchioles become invested with _____; ____ mature as the fetus approaches birth and ______ continue to be produced in the neonate.

Answer 10

capillaries (now called the terminal sacs= primitive alveoli); alveoli mature; alveoli

Question 11

The endoderm differentiates into the ____ epithelium that lines the airways and the ______ epithelium (ie, squamous type 1 pneumocytes & cuboidal type 2 pneumocytes) that lines the alveoli.

Answer 11

respiratory (& glandular) epithelium; specialized epithelium

Question 12

The mesenchyme surrounding the airways and alveoli (derived from splanchnopleuric mesoderm) gives rise to ______.

Answer 12

all the other components of their walls vasculature, connective tissue, cartilage, smooth muscle