What type of cell releases histamine? And what’s role of histamine in body?

Biology Today

Term: 2019 Summer

Final-term Exam

Name: ______________________ Time: _______________ Total: _________(100)

I. True or False:(3points each, 30points)

(1) Learning requires activity in the brain but not necessarily consciousness of the activity. ( )

(2) The length of time that a drug remains metabolically active in the body is measured by its full-life. ( )

(3) Drugs have both acute effects and chronic effects. ( )

(4) Health is the ability to return to homeostasis. ( )

(5) Specific immunity can be selectively turned off. This is called development of tolerance. ( )

(6) Pathogens are organisms that cause disease. ( )

(7) Biodiversity is measured by the number and variety of species, of which 60% are either insects or vascular plants. ( )

(8) Habitats support the interdependent lives of biological communities of species. ( )

(9) Sentinel species CNNNOT be used to monitor for pollution. ( )

(10)Because o f the greenhouse effect, increases in carbon dioxide emissions will cause a global warming trend. ( )

II. What type of cell releases histamine? And what’s role of histamine in body? (15points)

III. How do the terms stress and stressor differ? (10points)

IV. When body fluids such as blood are spilled, can cell-free HIV be killed by soap and water? Why or why not? (15points)

V. What is the difference between the terms prevalence and incidence? Under what conditions will prevalence increase if incidence remains the same? (20points)

VI. How many times more H+ ions are there in acid rain at pH 5 than in water at neutral p H? How many times more at pH5 than in ordinary water at pH6? (10points)

General Chemistry

Term: 2019 Summer

Final-term Exam

Name: ______________________ Time: _______________ Total: _________(100)

I. Choose the right answer: (3points each,18 points)

1. The environment performs 15kJ of work on the system, and the system loses 5kJ of heat to the environment, the internal energy of the system changes to ( )

(A) -15kJ (B) 10kJ (C) -10kJ (D) 15kJ

2. In the following molecules, the dipole moment is not zero is ( )

(A) BBr3            (B) SiCl4           (C) PCl5        (D) H2Se

3. Which of the following reagents should we choose to remove a small quantity of CuSO4 from ZnSO 4 solution ( )

(A) NH3·H2O (B) NaOH (C) Zn (D) H2S

4. Which of the following Compound that have ionic bonds, covalent bonds and coordination bonds together: ( )

(A)H3PO4 (B) Ba(NO3)2 (C) NH4Cl (D) NaOH

5. Which of the following cations will NOT precipitate while treated with HCl(l). ( )

(A)Ag+ (B) Hg22+ (C) Pb2+ (D) Cd2+

6. In F - Cl — Br -I order, the incorrect regularity of halogen is ( )

(A) X- ionic radius: F- < Cl- < Br – < I-

(B) electronegativity: F > Cl > Br > I

(C) Acid: HF > HCl > HBr > HI

(D) ionic polarizability: F- < Cl- < Br – < I-

II. True of False(3points each,12 points)

1. O3 is a nonpolar molecule. ( )

2. H3BO3 is a weak ternary acid. ( )

3. (Go is a constant for a particular reaction at a given temperature. ( )

4. The sign of (Go tells us not only the relative amounts of products and reactants when equilibrium is reached, but also the direction of the net reaction. ( )

III. Name these compounds: (3points each,15 points)

(a) K2HPO4

(b) K2Cr2O7 ,

(c) Al(OH)3,

(d) Na2CO3·10H2O,

(e) LiNO3,

IV. Classify each of these molecules as alcohol, aldehyde, ketone, carboxylic acid, amine, or ether: (3points each,15 points)

image1.emf(a)

H

3

COCH

2

CH

3

(b)

H

2

NCH

2

CH

3

(c)

CH

3

CH

2

C

O

H

(d)

H

3

CCCH

2

CH

3

O

(f)CH

2

CHCH

2

COOH

NH

2

V. Sodium bicarbonate (NaHCO3) is called baking soda because when heated, it releases carbon dioxide gas, which is responsible for the rising of cookies, doughnuts, and bread. HCO3- , its conjugate base is , its conjugate acid is .

(5 points)

VI Nitrous oxide (N2O) is also called “laughing gas.” Itcan be prepared by the thermal decomposition of ammonium nitrate (NH4NO3). The other product is H2O. (a) Write a balanced equation for this reaction.(b) How many grams of N2O are formed if 0.46 mole of NH4NO3 is used in the reaction? (15 points)

VII. HCl gas can be prepared by concentrated H2SO4 and NaCl, while HI gas can not be prepared by concentrated H2SO4 and KI. Why? (5points)

VIII. At the start of a reaction, there are 0.249 mol N2, 3.21×10-2mol H2, and 6.42×10-4 mol NH3 in a 3.50-L reaction vessel at 750C. If the equilibrium constant (Kc) for the reaction is 1.2 at this temperature, decide whether the system is at equilibrium. If it is not, predict which way the net reaction will proceed. (15 points)

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