Blood, Bone Marrow and Lymphoid

What are the functions of whole blood?

- transport: water, solute, cells
- temp regulation
- water balance

Whole blood is comprised of _______% plasma and _______% cells

60; 40

What is plasma made up of mostly? What else is in it?

water; proteins and other solutes

Erythrocytes can be found in what numbers? What is the life span?

X,000,000; months

Platelets (PLTs) can be found in what numbers? What is the life span?

X00,000; week

Leukocytes can be found in what numbers? What is the life span?

X,000; hours-days or years

What is the most numerous cell in the blood?

erythrocytes

What is the function of RBC?

carry O2 and CO2
acid-base homeostasis

Why does a RBC have a biconcave shape?

high surface-to-volume ratio

The RBCs, WBCs and thrombocytes of birds, reptiles, amphibians and fish are _________

nucleated

What animals have nucleated RBCs, WBCs and thromocytes?

birds, reptiles, amphibians and fish

What are the least numerous blood cells?

leukocytes

What is the function of leukocytes?

inflammation
immune response

List the types of leukocytes:

neutrophils
lymphocytes
monocytes
eosinophils
basophils

What kind of leukocyte is this?

neutrophil

What leukocytes are granulocytes?

neutrophils, eosinophils and basophils

What kind of leukocyte is this?

heterophil (neutrophil)

What leukocyte plays a big role in adaptive immune response?

lymphocyte

Lymphocytes play a major role in ___________ immune response

adaptive

What cells do leukocytes use for humoral immunity? cell-mediated immunity?

humoral = B-cells and plasma cells
cell-mediated = T-cells

What kind of leukocyte is this?

lymphocyte

Monocytes differentiate into ___________ in tissue

macrophages

What are the functions of macrophages?

phagocytosis
Antigen presentation to T-lymphocytes
iron storage

What type of leukocyte is this?

monocyte

What type of leukocyte is frequently vacuolated?

monocyte

What type of leukocyte is present in low numbers?

eosinophils

What is the function of eosinophils?

modulate delayed and immediate types of hypersensitivity reactions

What type of leukocyte is this?

eosinophil

What type of leukocyte contains many arginine-rich proteins?

eosinophils

What type of leukocyte is rare to see in healthy animals?

basophils

Basophils contain _________ and many other proteins

histamine

What type of leukocyte is this?

basophil

What is the second most numerous blood cell?

platelets

What is the function of platelets?

primary hemostasis (clotting)
primary inflammatory response

Do erythrocytes, leukocytes or platelets have the smallest diameter and volume?

platelets

Red marrow is richer in __________

hematopoietic cells

Yellow marrow is richer in _________

fatty tissue

What marrow produces all blood cells?

red

What marrow stores iron?

red

Yellow marrow can ____________ red marrow

replace

What marrow can change with age?

yellow

What is the large and small arrows pointing to?

large = boney trabeculae
small = hematopoietic cells and adipocytes

Bone marrow cellularity varies with age: neonate = _______% young animal = _____% older animals = _______%

neonate = 100%
young animal = 80%
older animals = 25-50%

What are the yellow lines surrounding?

sinusoidal capillaries

What are the sites of hematopoiesis in the bone marrow of post natal animals?

proximal end of femur and humerus
pelvis
sternum

What organs have a very little job in hematopoiesis?

liver and spleen

Label this image

1 = rubriblast
2 = prorubricyte
3 = rubricyte
4 = metarubricyte
5 = polychromatophilic RBC
6 = mature RBC

What kind of stain is being used in this image?

Wright stain

granulopoiesis occurs in the _________

bone marrow

Granulopoiesis is regulated by ____________ and ___________

colony stimulating factors (CSF) and inflammatory cytokines

Label this image

1 = myeloblast
2 = promyelocyte
3 = myelocyte
4 = metamyelocyte
5 = band neurophil
6 = segmented neutrophil

monopoiesis steps:

monoblast --> promonocyte --> monocyte

Thrombopoiesis

megakaryoblast --> promegakaryocyte --> megakaryocyte --> platelet

B lymphocytes mature in the __________ while T lymphocytes mature in the __________

bone marrow; thymus

B lymphocytes in birds mature in the _______

bursa of fabricius

What are the arrows and arrowheads pointing to?

arrows = plasma cells
arrowheads = small lymphocytes

What is the main site of hematopoiesis in adult mammals?

bone marrow

What are the functions of the lymphoid system?

phagocytosis
production of immunologically competent cells

Primary organs of the lymphoid system

bone marrow
bursa of fabricius
thymus

Lymphocytes migrate to secondary lymphoid organs for ___________ and _________

activation and presentation of antigen

What are the secondary organs of the lymphatic system?

lymph nodes
spleen
mucosal associated lymphoid tissue
tonsils

Where do T and B cells originate?

primary lymphatic organs

In primary lymphatic organs, access by antigen is ___________

strictly controlled

Primary lymphatic organs use apoptotic elimination of __________ cells

self-reactive

What do stromal cells do?

release factors aiding in cell differentation
macrophages

Where is the bursa of fabricius located?

dorsal wall of cloaca

What is this structure called?

cloacal bursa

Where is the thymus located in immature animals?

mediastinum cranial to heart

What is the thymus composed of?

epithelial reticulum and lymphocytes

Lymphocytic stem cells migrate from bone marrow and fill spaces between reticular epithelial cells. They develop into _____ cells which migrate to secondary organs

T

Why does the thymic cortex stain darker than the medulla?

more lymphocytes

What part of the thymus is the area of positive selection?

cortex

What structures are found near the medulla of the thymus?

tingible body macrophages

What part of the thymus has the area of negative selection?

medulla

Some medullary reticular epithelial cells form ___________

thymic corpuscles or Hassall's corpsucles

What are the lare central calcified or degenerated cells surrounded by concentric circles of keratinized cells called?

Hassall's corpuscles

What are the arrows indicating in this image?

Hassall's corpuscles

Arteries enter the thymus via the __________ junction within the connective tissue septa

corticomedullary

What creates the blood thymus barrier?

cortical capillaries

How do cortical capillaries for the blood thymus barrier?

continuous endothelium
perivascular CT
sheath of epithelial reticular cell processes

Why is the blood thymus barrier important?

decreased antigen access to thymus
limits interference with positive T cell selection and recognition of antigens as self

The thymus is active in ________ animals and involutes after _________

young; sexual maturity

What happens during thymic invoution?

lymphocytes get replaced by adipocytes

lymph nodes filter antigens from ____________ before returning it to __________

lymph; bloodstream

Spleen filters antigens from _______. It doesn't use _________ vessels

blood; lymphatic

What secondary lymphatic organ produces a local immune response?

mucosal associated lymphoid tissue

The capsule of the lymph node has what kind of tissue?

dense, irregular
trabeculae

In the cortex of lymph nodes, the lymphoid follicles are rich in ______ cells

B

In lymph nodes, the paracortex is rich in _____ cells

T

vessel flow of the lymph node

afferent lymphatic vessel
subcapsular sinuses
cortical (trabecular sinuses)
medullary sinuses
efferent lymphatic vessel

What is located in the cortex of the lymph node?

lymphoid follicles
paracortex
high endothelial blood vessels

What is located in the medullary cords of lymph nodes?

macrophages
lymphocytes
plasma cells

What is located in the medullary sinus of lymph nodes?

macrophages
reticular cells

What two structures are located in the medulla of the lymph node?

medullary cords and sinuses

When stimulated by antigen, lymphoid follicles change histologic morphology from _____________ to ___________

primary lymphoid follicles to secondary

What lymphoid follicle has a germinal center?

secondary

The paracortex contains high endothelial venules lined by _______ epithelium which allow _________ of lymphocytes

cuboidal; extravasation

The cortex and medulla of the lymph node are switched in what animal?

pig

hemal nodes are predominantly seen in _________. They have a ________ color

ruminants; dark

Hemal nodes do not have a ___________ supply

lymphatic