A&P II Trimester 1 Review

How many oxygen must hemoglobin always have in order to function? What is this called?

Each of the four subunits contains a heme ( contains iron) molecule, where the oxygen itself is bound through a reversible reaction, meaning that a hemoglobin molecule can transport four oxygen molecules at a time. hemoglobin with four oxygen is called Haemoglobin

Be able to describe the steps in the activation of a protein hormone.

Hormones activate target cells by diffusing through the plasma membrane of the target cells (lipid-soluble hormones) to bind a receptor protein within the cytoplasm of the cell, or by binding a specific receptor protein in the cell membrane of the target cell (water-soluble proteins). In both cases, the hormone complex will activate a chain of molecular events within the cell that will result in the activation of gene expression in the nucleus.

Name an example of a gonadotropic hormone from the anterior pituitary.

Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) they stimulate the gonads - in males, the testes, and in females, the ovaries.

All releasing hormones originate in which area of the brain?

Releasing hormones are sent from the hypothalamus to the anterior pituitary gland to control the release of hormones from the anterior pituitary.

Where are the receptors for steroid hormones located?

The receptors for steroid hormones are located inside the cell, instead of on the membrane surface like most other signal receptors; located inside target cells, in the cytoplasm or nucleus, and function as ligand-dependent transcription factors; After a steroid hormone molecule has diffused into the target cell, it binds to a receptor molecule to form a hormone-receptor complex. The hormone-receptor complex acts within the nucleus, by activating certain genes within the cell.

Identify hormones from the anterior pituitary and those that are not.

The six anterior pituitary hormones are: growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin (PRL).

Where is the hormone found that regulates circadian rhythm?

The suprachiasmatic nucleus (SCN), located in the anterior hypothalamus above the optic chiasm, constitutes the major site of circadian rhythm regulation. Melatonin functions as a feedback regulator on SCN

What causes vasoconstriction in Hemostasis and why

Vasoconstriction is mediated by contraction of the smooth muscles lining a blood vessel. Vasoconstriction is caused by thromboxane A2 from activated platelets and injured epithelial cells, nervous system reflexes from pain, and direct injury to vascular smooth muscle.

Be able to describe Anemia and the different types we discussed in class.

aplasticanemia: bone marrow damaged, toxic chemicals, radiation hemolytic anemia: RBCs destroyed, toxic chemicals sickle cell anemia: abnormal shape of RBCs, defective gene iron deficiency anemia: hemoglobin deficient, lack of iron pernicious anemia: excess of immature RBCs, inability to absorb B12 can cause brain damage Thalassemia: hemoglobin deficient, RBCs short-lived, defective gene

Another name for the second messenger in protein hormone activation is?

cAMP (cyclic adenosine monophosphate) epinephrine-stimulated cAMP synthesis

Know what is produced in the Anterior and Posterior pituitary. What are the Anterior and Pituitary also referred to as?

the posterior pituitary (neurohypophysis) is neural tissue and produces Antidiuretic hormone and oxytocin,whereas the anterior pituitary (also known as the adenohypophysis) is glandular tissue and produces Growth hormone, Prolactin,Thyroid-stimulating hormone, Adrenocorticotropic hormone, Follicle-stimulating hormone, and Luteinizing hormone

Be able to describe the steps of Hemostasis.

•Hemostasis involves three phases -1. Platelet plug formation -2. Vascular spasms -3. Coagulation •1. Collagen fibers are exposed by a break in a blood vessel •Platelets become "sticky" and cling to fibers •Anchored platelets release chemicals to attract more platelets (Positive Feedback!) •Platelets pile up to form a platelet plug •2. Anchored platelets release serotonin •Serotonin causes blood vessel muscles to spasm •Spasms narrow the blood vessel, decreasing blood loss •3. Injured tissues release thromboplastin •PF3 (a phospholipid) interacts with thromboplastin, blood protein clotting factors, and calcium ions to trigger a clotting cascade •Prothrombin activator converts prothrombin to thrombin(an enzyme) •Thrombin joins fibrinogen proteins into hair-like fibrin •Fibrin forms a meshwork(the basis for a clot)

Where are the beta cells of the endocrine system located?

the beta cells are located in the pancreatic islet cells; the most abundant of the islet cells

What hormones do Beta cells produce?

Beta cells (B cells) produce insulin and amylin

Describe the mechanism for regulation of erythrocyte production. What happens when a person moves to high altitudes? Be sure to discuss the negative feedback regulation of the hormone erythropoietin.

erythopoiesis is the product of erythocytes (red blood cells). The process starts through the stimulus of low O2 which is detected by the kidneys (endocrine response). The kidneys send the hormone erythropoietin into the bloodstream and that reaches the bone marrow through the blood. Erythroblasts increase RBC production, and maturation occurs. Then the RBC goes through its immature stage called reticulocyte. Finally, mature RBCs are released into the blood and O2 capacity is eventually increased. The negative feedback mechanism of the erythropoietin cause the cycle to stop when O2 levels return to normal. When a person moves to high altitudes, they take in less oxygen. This cause the amount of blood being pumped with each heart beat to increase, and increases blood pressure as the body adapts to the lower oxygen level. Therefore, in high altitude a person has a higher amount of haemoglobins blood increases the amount of oxygen it carry's.

What nutrients are required for hemoglobin synthesis?

iron, vitamin B12, viamin A, folate, riboflavin, and copper are required for the proper production of hemoglobin

activation of a protein hormone

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Where are the receptors for water soluble hormones located?

part of the plasma membrane of target cells; on the plasma membrane