BIO 169 MIDTERM EXAM 2026/2027 QUESTIONS AND
SOLUTIONS RATED A+
✔✔Flow of lymph from lymphatic capillaries through the various types of lymph vessels
until it is returned to the cardiovascular system - ✔✔1. Lymphatic capillaries
2. collecting lymphatic vessels
3. lymph nodes
4. lymphatic trunks
5. lymphatic ducts
6. subclavian veins
7. bloodstream
✔✔name the 2 categories of lymphoid structures and identify components of the body
that belong to each category - ✔✔-Primary lymphoid structures : formation and
maturation of lymphocytes ... red bone marrow and thymus
-Secondary lymphoid structures : not involved in lymphocyte formation , house both
lymmphocytes and other immune cells following formation, sites where immune
response is initiated , lymph nodes, spleen, tonsils, lymphoid nodules, MALT
✔✔Describe the location and general function of red bone marrow - ✔✔location:
Spongy bone of selected bones
function: development of all formed elements; site of B lymphocyte maturation
✔✔Identify the unique step required by T lymphocytes in their maturation - ✔✔migrate
from red bone marrow as thymocytes to thymus to mature and protected by a well-
formed blood-thymus barrier
✔✔Describe the structure and general function of the thymus - ✔✔bilobed organ
located in the superior mediastinum
functions in T-lymphocyte maturation
grows until puberty max weight 30-50 grams
✔✔Describe both the structure and function of lymph nodes - ✔✔small, round or oval
encapsulated structures located along pathways of lymphatic vessels, vary in sizes 0.1-
2.5 cm, 500-700 throughout body. both superficially and deep in body, typically in
clusters that receive lymh from selected body regions
function in filtering of lymph and sites for initiating an immune response if harmful
substances are found in the lymph
ex: cervical, axillary, and ingunial
✔✔Describe the location, structure, and function of the spleen - ✔✔largest lymphoid
organ, about 12 x 7 x 3 cm, located left upper quadrant of abdomen, inferior to the
diaphragm and adjacent to ribs 9-11 , lateral to left kidney and posterolateral to stomach
surrounded by connective tissue capsule
SOLUTIONS RATED A+
✔✔Flow of lymph from lymphatic capillaries through the various types of lymph vessels
until it is returned to the cardiovascular system - ✔✔1. Lymphatic capillaries
2. collecting lymphatic vessels
3. lymph nodes
4. lymphatic trunks
5. lymphatic ducts
6. subclavian veins
7. bloodstream
✔✔name the 2 categories of lymphoid structures and identify components of the body
that belong to each category - ✔✔-Primary lymphoid structures : formation and
maturation of lymphocytes ... red bone marrow and thymus
-Secondary lymphoid structures : not involved in lymphocyte formation , house both
lymmphocytes and other immune cells following formation, sites where immune
response is initiated , lymph nodes, spleen, tonsils, lymphoid nodules, MALT
✔✔Describe the location and general function of red bone marrow - ✔✔location:
Spongy bone of selected bones
function: development of all formed elements; site of B lymphocyte maturation
✔✔Identify the unique step required by T lymphocytes in their maturation - ✔✔migrate
from red bone marrow as thymocytes to thymus to mature and protected by a well-
formed blood-thymus barrier
✔✔Describe the structure and general function of the thymus - ✔✔bilobed organ
located in the superior mediastinum
functions in T-lymphocyte maturation
grows until puberty max weight 30-50 grams
✔✔Describe both the structure and function of lymph nodes - ✔✔small, round or oval
encapsulated structures located along pathways of lymphatic vessels, vary in sizes 0.1-
2.5 cm, 500-700 throughout body. both superficially and deep in body, typically in
clusters that receive lymh from selected body regions
function in filtering of lymph and sites for initiating an immune response if harmful
substances are found in the lymph
ex: cervical, axillary, and ingunial
✔✔Describe the location, structure, and function of the spleen - ✔✔largest lymphoid
organ, about 12 x 7 x 3 cm, located left upper quadrant of abdomen, inferior to the
diaphragm and adjacent to ribs 9-11 , lateral to left kidney and posterolateral to stomach
surrounded by connective tissue capsule
