Blood and Lymph

Question 1

What are the fluid connective tissues?

Answer 1

Blood and lymph

Question 2

What are the characteristics of blood? (4)

Answer 2

Composed of blood cells and plasma
Distributes nutrients, oxygen and hormones to body cells
Carries metabolic wastes away from cells and to the kidneys for excretion
Transports specialized cells that provide protection against infection and disease

Question 3

What are the physical characteristics of blood? (4ish)

Answer 3

Volume in body: 5-6L in males and 4-5L in females
pH: 7.35-7.45, very sensitive
Temperature: 38C at core
Normovolemic is normal volume, hypovolemic is volume too low, and hypervolemic is volume too high

Question 4

What are the formed elements in blood? (3) and the subtypes.

Answer 4

Red blood cells (erythrocytes): carry O2 and CO2, 99% of cells in blood
White blood cells (leukocytes): neutrophils destroy bacteria, eosinophils are anti-inflammatory and allergic response, basophils are inflammatory response, monocytes become macrophages, and lymphocytes are immune response
Platelets: clotting reaction, stems outflow of blood, not a cell, they are pieces of a cell

Question 5

What is the structure of red blood cells? (3)

Answer 5

Biconcave disc-shaped cells
Plasma membrane surrounds cytoplasm containing water (66%) and proteins (33%): intracellular structures, including nucleus, are ejected from cell during development (not needed for main purpose of gas transport)
No machines makes it hard to repair anything therefore they usually die when damaged, want to transport O2 and these machines use O2 therefore not efficient if they had them

Question 6

What is the structure of platelets? (3)

Answer 6

Formed from large stem cells called megakaryocytes in the red bone marrow
Platelets are membrane-bound enzyme packets that pinch off from the cytoplasm of the megakaryocytes
Responsible for the clotting reaction in the blood

Question 7

What is the structure of blood vessels? What way does blood flow in which vessels?

Answer 7

Pathways for blood to circulate throughout the body
Blood flows in two directions: away from the heart (arteries, arterioles, continuous capillaries), towards the heart (veins, venules, fenestrated capillaries)

Question 8

What are the three layers if the vessel walls?

Answer 8

Tunica interna: composed of simple squamous epithelium (endothelium) and thin layer of connective tissue, many folds to increase SA
Tunica media: thickest layer, composed of elastic fibers and smooth muscle
Tunica externa: composed of connective tissues, attaches vessel to surrounding connective tissue

Question 9

What are the 4 types of arteries in order of closest to heart to farthest away?

Answer 9

1. Elastic artery: largest diameter, closest to the heart due to big bolus of blood gets pushed therefore vessel is mobile, large tunica interna
2. Muscular artery: lots of muscle in tunica media, large control in dilating and constricting
3. Arteriole: limited tunica externa, high media, many of them
4. Continuous capillary: actual exchange and diffusion of gas across membrane occurs

Question 10

What are the 4 types of veins in order of closest to heart to farthest away?

Answer 10

1. Large vein: large tunica externa, close to heart to bring lots of blood back
2. Medium sized vein: big tunica media
3. Venule: large tunica externa, bit bigger than arteriole
4. Fenestrated capillary: more pores in walls between cells therefore debris can get in and go back to heart

Question 11

What is the structure of the elastic (conducting) vessels? (4)

Answer 11

Largest diameter of arteries
Tunica media contains high density of elastic fibers
Stretch and recoil in response to pumping of heart
Even out pressure surges

Question 12

What is the structure of muscular (distributing) arteries? (4)

Answer 12

Medium sized arteries
Distribute blood to skeletal muscles and internal organs
Tunica media contains predominantly smooth muscle
Able to vasoconstrict (close) and vasodilate (open)

Question 13

What are the structure of arterioles? (5)

Answer 13

Small to microscopic vessels
Poorly defined tunica externa
Tunica media composed of few smooth muscle cells
Deliver blood to capillaries
Change in luminal diameter regulates blood pressure

Question 14

What is the structure of capillaries? (3)

Answer 14

Smallest blood vessels
Connect arterioles to venules
Mediate exchange between blood and surrounding tissues

Question 15

What are some differences between continuous and fenestrated capillaries?

Answer 15

Fenestrated capillaries have pores to allow for more diffusion

Question 16

What structure allows for more control over what gets into vasculature in the endothelial cells?

Answer 16

Diaphragm

Question 17

How does control of blood flow work in capillary beds?

Answer 17

Precapillary sphincters control blood flow through capillaries (small and large opening)
Metarterioles shunt blood through capillary bed, shunt blood directly arteriole to venule when there is no high O2 demand in particular tissue

Question 18

What is the structure and function of veins? And venules? And medium and large veins?

Answer 18

Collect blood from organs and tissues and return it to the heart
Venules: collect blood from capillaries, wall composed primarily of tunica interna
Medium and large veins: tunica externa thickest layer, blue veins more superficial b/c want to protect arteries in the event of injury

Question 19

What is the purpose of valves? (4)

Answer 19

Valves in the walls of veins prevent backflow of blood
Venous compression caused by contraction of adjacent muscles aids in maintaining blood flow
Mostly in extremities because fighting gravity to return to heart
May break down as we age

Question 20

How are the major arteries and veins divided?

Answer 20

By region: thorax, head and neck, abdominopelvic cavity, upper and lower extremities

Question 21

What are the right arteries in the thorax?

Answer 21

Aortic arch with the brachiocephalic trunk branching off of it and bifurcating into the right subclavian and right common carotid, and off the subclavian is the vertebral which feeds parts of the brain
The internal thoracic comes off the brachiocephalic trunk and branches come off (intercostal arteries)
The aorta is called the thoracic aorta

Question 22

What are the left arteries in the thorax?

Answer 22

The left common carotid artery branches off the aorta as well as left subclavian artery, and axillary
Intercostal branch off the aorta and travel intercostal space
Descending aorta ends in diaphragm

Question 23

What are the arteries in the head and neck?

Answer 23

The brachiocephalic trunk which branches into carotid sinus (reads blood pressure, signals brain, brain fine tunes BP) and the external carotid
Also the internal thoracic branch off, thyrocervical trunk branches off subclavian and feeds thyroid and cervical regions, as well as vertebral and internal carotid

Question 24

In the abdomen what are the branches on the RT side of the abdomen?

Answer 24

Abdominal aorta and into the celiac trunk, and then off of this comes the common hepatic , splenic, and gastric arteries, then comes the superior mesenteric which branches down. Off the superior mesenteric artery there are branches to the colon and small intestine
Then the right common iliac, right internal iliac and right external iliac

Question 25

What are the left abdominal arteries?

Answer 25

Inferior mesenteric goes to colon, anal, rectum, branches to colon, then the left common iliac and left external iliac

Question 26

What are the arteries in the upper extremities?

Answer 26

Subclavian, axillary, then deep brachial and brachial, then radial and ulnar, palmar arches and digital

Question 27

What are the arteries of the lower extremities?

Answer 27

Common iliac, branches off into the internal iliac and external iliac, femoral as well once past the ligament, then there is a branch to the knee and popliteal, posterior and anterior tibial, fibular , pedal arches and digital

Question 28

What are the branches of the veins in the thorax that come off the superior vena cava in the upwards direction? What does the superior vena cava turn into being called?

Answer 28

Internal jugular, external jugular, then the SVC turns into being called the subclavian

Question 29

What veins come off the SVC downwards? What is the large vein that comes out the bottom of the heart?

Answer 29

Azygos, internal thoracic, hemiazygos, intercostals Inferior vena cava

Question 30

What are the veins in the neck and head?

Answer 30

Superior vena cava branches into the right brachiocephalic , then into subclavian. Off the RT BC comes the internal jugular, external jugular and the vertebral

Question 31

What are the major veins below the diaphragm coming from the inferior vena cava?

Answer 31

Hepatics, renals, gonadals RT/LT common iliac, RT/LT internal iliac, RT/LT external iliac

Question 32

What are the components of the hepatic portal system? What is the purpose of this system?

Answer 32

Hepatic portal vein, which branches into the gastrics and splenics, as well as the superior mesenteric vein and inferior mesenteric vein Blood from the digestive tract drains directly to the liver

Question 33

What are the veins in the upper extremity?

Answer 33

Subclavian, branches into the axillary and cephalic, axillary branches into the brachial and basilic, then radial and ulnar and palmar arches and digitals

Question 34

What are the veins in the lower extremities?

Answer 34

External iliac and common iliac/ internal iliac as well as deep femoral and femoral, great saphenous (superficial drainage), and popliteal, posterior and anterior tibial, small saphenous and fibular, as well as pedal arches and digitals

Question 35

What are the two bodily fluids?

Answer 35

Intracellular fluid: cytoplasm, nucleoplasm Extracellular fluid: blood plasma (in circulatory system), interstitial fluid (bathes the cells of the body, filtrate of fluid and small solutes out of capillaries to the areas surroundings, called lymph when it enters the lymphatic vessels, composed of lymphocytes and lymph fluid, lymph fluid is a dilute solution of proteins and excess of interstitial fluid)

Question 36

What is the comparison between lymph flow and blood flow?

Answer 36

Blood is actively pumped through vessels by heart Lymph flows passively along a pressure gradient (NO PUMP)

Question 37

What are the structure of the lymphatic vessels?

Answer 37

Lymphatic system is extremely low pressure, vessels are very thin (not a lot of integrity between cells)

Question 38

What are the valves in the lymph system?

Answer 38

Large number of valves because passive flow allows pressure to be easily changed, therefore prevents backflow of lymph

Question 39

What are the functions lymphatic system?

Answer 39

Produce, maintain and distribute lymphocytes: function in immune response Assists with maintaining normal blood volume: vascular pressure forces water and solutes across capillary membrane into interstitial space (3.6L, 72% of blood volume, enters interstitial fluid every day) and fluid is returned to the vasculature by lymph vessels Alternate route for transport of hormones, nutrients, metabolic waste (some lipids absorbed by digestive tract enter bloodstream via lymph rather than capillaries of the vasculature, thus these lipids do not go to liver for processing, go straight to the heart)

Question 40

What are the two lymphatic ducts?

Answer 40

Right lymphatic duct which drains right upper extremity and RT head/neck and RT thorax Thoracic duct which drains LT head/neck, LT upper extremity, LT thorac and all lower abdomen extremities These empty into large thoracic veins such as azygos vein and cisterna chyli

Question 41

What are the three types of lymphocytes?

Answer 41

B-lymphocytes, T-lymphocytes and NK cells

Question 42

What are the B-lymphocytes?

Answer 42

Originate and become immunocompetent in bone marrow, reside in lymph nodes, spleen and lymphoid tissue Produce antibodies targeted to specific antigens: antibody-mediated immunity

Question 43

What are the T-lymphocytes?

Answer 43

Originate in the bone marrow and continue development and become immunocompetent in the thymus gland Cytotoxic T-cells destroy pathogens and abnormal cells (cell mediated immunity) Regulatory T-cells regulate the immune responses, reside in spleen, other lymphoid organs, bone marrow

Question 44

What are the natural killer cells?

Answer 44

Originate and become immunocompetent in the bone marrow and continuously circulate through peripheral tissue (immunological surveillance cells) Respond to cancer cells

Question 45

What are the lymphatic organs?

Answer 45

Discrete structures enclosed by a fibrous connective tissue capsule Primary- produce, maintain and store lymphocytes, contain stem cells that generate B, T, and NK cells Secondary (peripheral) structures: where most immune responses are initiated, activated lymphocytes divide to produce additional lymphocytes of the same type, the front line where invading bacteria were first encountered

Question 46

What is the thymus gland?

Answer 46

Lies posterior to manubrium in the superior mediastinum, two lobes, large in early life, it undergoes involution in later life, source of T lymphocytes

Question 47

What is the spleen?

Answer 47

Located along lateral curvature (left) of stomach between ribs 9-11 Largest lymphoid organ Filters the blood, removing abnormal blood cells and components by phagocytosis Stores ions recycled from metabolized RBC Initiates immune response by B and T cells in response to circulating antigens

Question 48

What is a lymph node?

Answer 48

Oval lymphoid organs 1-25 mm in diameter Many afferent vessels penetrate fibrous tissue A single efferent vessel exits the node Lymph nodes filter the lymph, removing 99%+ of antigens Resident T cell, B cells and macrophages (major site of immune response to antigens) Lymph glands: large nodes at the base of neck, axillae, groin Swollen glands: enlarged nodes due to the inflammation of infection

Question 49

What are the lymphoid tissue?

Answer 49

Connective tissues dominated by lymphocytes Diffuse (mucous membranes of respiratory and urinary tract) Nodules: oval shaped aggregations of densely packed lymphocytes (1mm in diameter) supported by dense reticular fibres, boundaries often indistinct due to lack of fibrous capsules Mucosa of digestive tract: wall of pharynx (tonsils), lining of small intestine (peyer's patches), appendix (mass of fused lymphoid nodules, lymphocytes not always effective against infection (tonsillitis, appendicitis)

Question 50

What are lymphoid nodules?

Answer 50

Densely packed accumulations of lymphocytes, mount an immune response to antigens

Question 51

What are the tonsils?

Answer 51

Aggregates of lymphocytes nodules in the pharynx, remove pathogens from inspired air and food

Question 52

What is involved in the drainage of the breast?

Answer 52

Axillary lymph nodes (75% of breast drainage) Lymph nodes and mammary glands Cancer cells metastasize (migrate) along lymphatics and become trapped in lymph nodes