Term
What are the major endocrine organs? |
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Definition
Superiorly to Inferiorly
Pineal Gland
Hypothalamus
Pituitary (anterior and posterior)
Thyroid Gland
Parathyroid Glands
Thymus
Adrenal Glands
Pancreas
Ovary (female)
Testes (male)
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Term
What are the Anterior Pituitary Hormones? |
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Definition
GH: Growth Hormone
TSH: Thyroid Stimulating Hormone
ACTH: Adrenocorticotropic Hormone
PRL: Prolactin
Gonadotropins:
FSH: Follicle Stimulating Hormone
LH: Luteinizing Hormone
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Term
What are the chief effects of GH (Growth Hormone)? |
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Definition
- Mobilizes fats and spares glucose
- stimulates bone and muscle growth
Growth promoting effects mediated indirectly by IGFs (Insulin-like Growth Factors) |
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Term
What is Hyposecretion and Hypersecretion of Growth Hormone result in |
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Definition
Hyposecretion: Pituitary Dwarfism in children
Hypersecretion: Gigantism in children; Acromegaly in adults |
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Term
What are the effects of Thyroid Stimulating Hormone (TSH)? |
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Definition
Stimulates Thyroid Gland to release Thyroid Hormones
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Term
Effects of Hypersecretion and Hyposecretion of TSH |
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Definition
Hyposecretion: Cretinism in children
Hypersecretion: hyperthyroidism-effects similar to those of Graves' disease |
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Term
What are the effects of Adrenocorticotropic Hormone? ACTH |
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Definition
Stimulated by CRH
Promotes release of glucocorticoids, androgens, and mineralcorticoids from adrenal cortex |
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Term
What is the result of Hyposecretion and hypersecretion of ACTH? |
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Definition
Hyposecretion is really rare
Hypersecretion results in Cushing's disease |
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Term
What are the effects of FSH?
Follicle Stimulating Hormone |
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Definition
Stimulated by GnRH
In females: stimulates ovarian follicle maturation and estrogen production
In males: stimulates sperm production |
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Term
What is the effect of LH?
(Luteinizing Hormone) |
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Definition
Stimulated by GnRH
In females: triggers ovulation and stimulates production of estrogen and progesterone
In males: promotes testosterone production |
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Term
What are the effects of PRL (Prolactin)? |
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Definition
Inhibited by PIH (dopamine)
promotes lactation of the breasts |
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Term
What are tropic hormones? |
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Definition
Hormones that effect other endocrine glands to release hormones. |
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Term
What are the posterior pituitary hormones? |
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Definition
ADH-Anti-Diuretic Hormone
Oxytocin |
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Term
What are the effect of ADH? |
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Definition
Stimulates kidney tubules cells to reabsorb water |
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Term
What are the effects of oxytocin? |
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Definition
Stimulates uterine contraction and initiates labor.
Initiates milk ejection of the breasts. |
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Term
Describe the structure of the posterior pituitary gland |
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Definition
The posterior pituitary gland is made largly by the axons of the hypothalamus and it stores ADH and oxytocin that have been synthesized in the hypothalamus.
The Infundibulum is the stalk connecting the hypothalamus to the pituitary gland
the axons running through the infundibulum to the posterior pituitary are known as the hypothalamic hypopheseal tract |
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Term
What are the two groups of hormones produced by the Thyroid? |
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Definition
Thyroxine (T4)
Triiodothyronine (T3) |
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Term
How do T3 and T4 effect the body? |
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Definition
- T4 is the major hormone secreted by the thyroid follicles. T3 is formed at the target tissues by removal of on Iodine atom.
- T4 and T3 are reffered together as TH
- TH effects virtually every cell in the body by turning on transcription of genes that are concerned with glucose oxidation.
- TH increases metabolic rate and body heat production... i.e. the calorigenic effect.
- TH is important in regulating tissue growth and development. It is critical for normal skeletal and nervous system development as well as maturation of reproductive capabilites.
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Term
What is the function of PTH?
(Parathyroid Hormone) |
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Definition
PTH is critical in maintaining the calcium balance in the blood. |
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Term
What hormones does the Pancreas produce? |
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Definition
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Term
How do Insulin and Glucagon maintain homeostasis of blood sugar levels? |
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Definition
- High Blood Glucose: Pancreas secretes Insulin
- Insulin stimulates cells to take in glucose and liver to convert glucose to glycoge.
- Blood Glucose then falls back to normal range
- Low Blood Glucose: Pancreas secretes Glucagon
- Glucagon stimulates liver to convert stored Glycogen to glucose
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Term
What is the composition of whole blood? |
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Definition
- Plasma: 55%- the least dense component
- Buffy coat: >1% contains white blood cells and platelets
- erythrocytes: 45%- the most dense component
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Term
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Definition
Slightly Alkaline with a pH between 7.35 and 7.45 |
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Term
Describe the Structure of an erythrocyte |
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Definition
essentially a biconcave bag of hemoglobin
- Hemoglobin:
- two alpha chains and two beta chains of globin
- four heme groups
- Biconcave shape is maintained by the protein spectrin- which is deformable, allowing the cell some flexibility
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Term
What is the function of an erythrocyte? |
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Definition
transport gases through the body
- Oxygen: When erythrocytes pass through the pulmonary circuit, Iron in the heme groups of hemoglobin binds with oxygen: oxyhemoglobin
- deoxyhemoglobin: when the oxygen is released from the heme groups and delivered to the cells of the body.
- Carbaminohemoglobin: Carbon dioxide released from the cells binds to the amino acids of the globin chains to be eliminated through the lungs
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Term
What is the term for blood cell formation? |
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Definition
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Term
What is the term for red blood cell formation? |
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Definition
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Term
What is the term for the stem cell of all blood cells |
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Definition
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Term
What is the order in which a Hemocytoblast becomes an erythrocyte? |
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Definition
Hemocytoblast-->
phase 1: Ribosome synthesis-->
phase 2: hemoglobin synthesis-->
phase 3: ejection of nucleus "Reticulocyte"-->
*Reticulocyte is the stage in which it leaves the bone marrow
Reticulocyte matures to Erythrocyte in the blood stream |
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Term
What are the different types of Leukocytes? |
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Definition
Neutrophil
Eosinophil
Basophil
Lymphocyte
Monocyte |
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Term
What are the two classes of Leukocytes? |
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Definition
Granulocytes
Agranulocytes |
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Term
What are the structural characteristics of neutrophils? |
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Definition
- granulocytes
- 50-70% of WBCs
- lilac colored cytoplasm
- Neutro: because granules take up acidic and basic stains (red and blue)
- major phagocytes
- Nucleus has 3 to 6 lobes
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Term
What are the structural characteristics of Eosinophils? |
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Definition
- 2-4% of WBCs
- granules take up eosin- red, acidic stain
- lysosome like granules
- nucleus is bi-lobed
- destroys parasitic worms by degranulating
- numbers also increase during allergies and asthma
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Term
Describe the structural characteristics of Basophils |
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Definition
- <1% of WBCs
- granules contain histamine which increases inflamation by vasodilation and increases capillary permeability
- Baso-- takes up blue, basic stain
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Term
What are the structural characteristics of Lymphocytes? |
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Definition
- Agranulocyte
- 25% of WBCs
- Large spherical nucleus takes up most of the cytoplasm
- 2 types:
- B lymphocytes
- T lymphocytes
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Term
What are the structeral characteristics of Monocytes? |
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Definition
- Agranulocyte
- 3-8% of WBCs
- Largest of the WBCs
- Leave the blood stream and transform into macrophages
- occurs especially with chronic infections
- Phagocytize bacteria and deadd tissue debris
- Activate B and T lymphocytes
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Term
How are platelets formed? |
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Definition
When a Hemocytoblast becomes a Megakaryocyte, fragments of the plasma membrane come off and become platelets |
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Term
What clotting chemicals do platelets contain? |
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Definition
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Term
What is the function of platelets? |
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Definition
when there is a break in a vessel, platelets release chemicals to become sticky and form platelet plug. |
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