BIOL 235 MIDTERM 1 COMPREHENSIVE
QUESTIONS AND SOLUTIONS
◉ afferent lymphatic vessels
Answer: vessels through which lymph enters the node. Penetrate
the convex surface of the node at several points. contain valves
that open toward the centre of the node, directing the lymph
inward.
◉ sinuses
Answer: a series of irregular channels within the node that
contain branching reticular fibres, lymphocytes, and
macrophages. Lymph enters these from afferent lymphatic
vessels.
◉ efferent lymphatic vessels
Answer: medullary sinuses drain into one or two of these vessels,
which are wider and fewer in number than afferent vessels. They
contain valves that open away from the centre of the lymph node
to convey lymph, antibodies secreted by plasma cells, and
activated T cells out of the node.
◉ hilum
Answer: slight depression at which efferent lymphatic vessels
emerge from one side of the lymph node. Blood vessels also enter
and leave the node at this structure.
,◉ Spleen
Answer: largest single mass of lymphatic tissue in the body.
Located between stomach and diaphragm. Has a hilum, through
which passes the splenic artery, splenic vein, and efferent
lymphatic vessels.
◉ white pulp
Answer: lymphatic tissue in the spleen, consisting mostly of
lymphocytes and macrophages arranged around branches of the
splenic artery called central arteries. Within this tissue, B cells
and T cells carry out immune functions, similar to lymph nodes,
while spleen macrophages destroy blood-borne pathogens by
phagocytosis.
◉ red pulp
Answer: consists of blood-filled venous sinuses and cords of
splenic tissue called splenic cords. Splenic cords consist of red
blood cells, macrophages, lymphocytes, plasma cells, and
granulocytes. Veins are closely associated with this tissue. Within
this tissue, the spleen performs three functions related to blood
cells:
(1) removal by macrophages of ruptured, worn out, or defective
blood cells and platelets;
(2) storage of platelets, up to one-third of the body's supply; and
,(3) production of blood cells (hemopoiesis) during fetal life.
◉ mucosa associated lymphatic tissue (MALT)
Answer: different term for lymphatic nodules. Called this because
they are scattered throughout the lamina propria (connective
tissue) of mucous membranes lining the gastrointestinal, urinary,
and reproductive tracts and the respiratory airways.
◉ Lymphatic nodules (follicles)
Answer: egg-shaped masses of lymphatic tissue that are not
surrounded by a capsule.
◉ tonsils
Answer: five of these, which form a ring at the junction of the oral
cavity and oropharynx and at the junction of the nasal cavity and
nasopharynx. Strategically positioned to participate in immune
responses against inhaled or ingested foreign substances.
◉ pharyngeal tonsil (adenoid)
Answer: embedded in the posterior wall of the nasopharynx.
◉ palatine tonsils
Answer: lie at the posterior region of the oral cavity, one on either
side; these are the tonsils commonly removed in a tonsillectomy.
, ◉ lingual tonsils
Answer: located at the base of the tongue, may also require
removal during a tonsillectomy.
◉ innate (nonspecific) defences
Answer: includes the external physical and chemical barriers
provided by the skin and mucous membranes. It also includes
various internal defences, such as antimicrobial substances,
natural killer cells, phagocytes, inflammation, and fever.
◉ First line of defence
Answer: skin and mucous membranes
◉ epidermis
Answer: outer epithelial layer of skin. Many layers of closely
packed, keratinized cells. Provides a formidable physical barrier
to the entrance of microbes. In addition, periodic shedding of
epidermal cells helps remove microbes at the skin surface.
◉ mucous membranes
Answer: line body cavities, secretes a fluid called mucus that
lubricates and moistens the cavity surface.
◉ mucus
QUESTIONS AND SOLUTIONS
◉ afferent lymphatic vessels
Answer: vessels through which lymph enters the node. Penetrate
the convex surface of the node at several points. contain valves
that open toward the centre of the node, directing the lymph
inward.
◉ sinuses
Answer: a series of irregular channels within the node that
contain branching reticular fibres, lymphocytes, and
macrophages. Lymph enters these from afferent lymphatic
vessels.
◉ efferent lymphatic vessels
Answer: medullary sinuses drain into one or two of these vessels,
which are wider and fewer in number than afferent vessels. They
contain valves that open away from the centre of the lymph node
to convey lymph, antibodies secreted by plasma cells, and
activated T cells out of the node.
◉ hilum
Answer: slight depression at which efferent lymphatic vessels
emerge from one side of the lymph node. Blood vessels also enter
and leave the node at this structure.
,◉ Spleen
Answer: largest single mass of lymphatic tissue in the body.
Located between stomach and diaphragm. Has a hilum, through
which passes the splenic artery, splenic vein, and efferent
lymphatic vessels.
◉ white pulp
Answer: lymphatic tissue in the spleen, consisting mostly of
lymphocytes and macrophages arranged around branches of the
splenic artery called central arteries. Within this tissue, B cells
and T cells carry out immune functions, similar to lymph nodes,
while spleen macrophages destroy blood-borne pathogens by
phagocytosis.
◉ red pulp
Answer: consists of blood-filled venous sinuses and cords of
splenic tissue called splenic cords. Splenic cords consist of red
blood cells, macrophages, lymphocytes, plasma cells, and
granulocytes. Veins are closely associated with this tissue. Within
this tissue, the spleen performs three functions related to blood
cells:
(1) removal by macrophages of ruptured, worn out, or defective
blood cells and platelets;
(2) storage of platelets, up to one-third of the body's supply; and
,(3) production of blood cells (hemopoiesis) during fetal life.
◉ mucosa associated lymphatic tissue (MALT)
Answer: different term for lymphatic nodules. Called this because
they are scattered throughout the lamina propria (connective
tissue) of mucous membranes lining the gastrointestinal, urinary,
and reproductive tracts and the respiratory airways.
◉ Lymphatic nodules (follicles)
Answer: egg-shaped masses of lymphatic tissue that are not
surrounded by a capsule.
◉ tonsils
Answer: five of these, which form a ring at the junction of the oral
cavity and oropharynx and at the junction of the nasal cavity and
nasopharynx. Strategically positioned to participate in immune
responses against inhaled or ingested foreign substances.
◉ pharyngeal tonsil (adenoid)
Answer: embedded in the posterior wall of the nasopharynx.
◉ palatine tonsils
Answer: lie at the posterior region of the oral cavity, one on either
side; these are the tonsils commonly removed in a tonsillectomy.
, ◉ lingual tonsils
Answer: located at the base of the tongue, may also require
removal during a tonsillectomy.
◉ innate (nonspecific) defences
Answer: includes the external physical and chemical barriers
provided by the skin and mucous membranes. It also includes
various internal defences, such as antimicrobial substances,
natural killer cells, phagocytes, inflammation, and fever.
◉ First line of defence
Answer: skin and mucous membranes
◉ epidermis
Answer: outer epithelial layer of skin. Many layers of closely
packed, keratinized cells. Provides a formidable physical barrier
to the entrance of microbes. In addition, periodic shedding of
epidermal cells helps remove microbes at the skin surface.
◉ mucous membranes
Answer: line body cavities, secretes a fluid called mucus that
lubricates and moistens the cavity surface.
◉ mucus
