1. MCAT Session 3

2. Physics Know all of the equations and units!!!!! Important things to remember from this section  Converging have + focal lengths  Diverging have – focal lengths  Virtual = upright image  Real = inverted image  Only converging mirrors can produce a real image

3. ANSWERS – Physics Exam 5 93. B103. B113. A 94. D104. C114. B 95. B105. A115. A 96. A106. C 97. B107. D 98. D108. C 99.D109. C 100. A110. A 101. C111. C 102. A112. C

4. Psychology and Sociology Difference Threshold – a just noticeable difference, describes the smallest difference that is sufficient for a change in stimulus to be noticed  More sensitive the sensory system = the smaller the change that is required for detection Weber’s Law – the change required to meet the difference threshold is a certain fraction of the originally presented stimulus.

5. Psychology and Sociology Exam 5 93. B103. C113. A 94. D104. A114. C 95. C105. B115. B 96. C106. B 97. A107. D 98. D108. A 99.B109. B 100. C110. C 101. A111. C 102. D112. A

6. Important things to know about bones: osteoblasts secrete collagen and create the bone matrix, become enveloped in bone and mature to osteocytes. Osteocytes exchange nutrients and waste with the bloodstream Osteoclasts are the ones that eat up bone. They “resorb” bone matrix and increase the blood concentration of calcium and phosphate “Blasts build bone, clasts consume”

7. Bone Hormones: PTH v. calcitonin PTH (parathyroid hormone) comes from the parathyroid(!), is a peptide hormone  It ultimately INCREASES blood Ca2+ through increasing: osteoclast bone resorption, osteoclast proliferation, renal Ca2+ reabsorption, Ca2+ uptake at GI, vitamin D derivation Calcitonin…  Comes from the thyroid and is also a peptide  Lowers blood Ca2+ by decreasing osteoclast activity and decreasing osteoclast proliferation Calcitonin “tones” down osteoclast activity

8. Bone Facts 2 types: spongy and compact Spongy bone has red marrow and is where hematopoeisis occurs (RBC proliferation) Compact bone has yellow marrow which is populated with adipocytes- It is where most Ca2+ and PO43- is stored Blood cells are red, fat cells are yellow

9. Bio Exam 6 Answers 116. C126. D136. A 117. A127. A137. B 118. D128. D138. C 119. B129. C 120. A130. D 121. B131. C 122.B132. A 123. A133. D 124. B134. C 125. C135. C

10. How to determine pH and hydrogen ion concentration [H+] = 1 x 10 -4 then the pH = 4 If the pH = 7 then the [H+] = 1 x 10 -7 If the [H+] = 4 x 10 -3 then the pH is between 2 and 3 (an estimation between 2 and 3 is sufficient for the MCAT)