1.Mg + O > X X +OH > Y

A. X is MgO and Y is MgOH
B. X is MgO and Y is MgH
C. X is MgOH and Y is MgO
D. X is MgO and Y is OHMg

2. Identify the pathway of carbon dioxide after the exchange of gases in the lungs?
A. Alveolus → bronchiole → bronchus→ trachea → nose
B. Alveolus → traches → bronchiole→ bronchi → nose
C. Nose→ bronchus→ trachea→ bronchiole → alveolus → nose
D. Trachea → bronchus → bronchiole→ alveolus→ nose

3. Choose the correct reaction.
A. CuSO₄ + FeSO₄ > Cu+Fe
B. Cu + FeSO₄ > CuSO₄ +Fe
C. CuSO₄ + Fe > FeSO₄ +Cu
D. FeSO₄ + Fe > FeSO₄ + F

4. Which of the following is a neutralization reaction?
A. Sodium chloride + Water→ Sodium hydroxide + Hydrochloric acid
B. Calcium carbonate + Water→ Calcium hydroxide + Carbon dioxide
C. Sodium hydroxide + Hydrochloric add →Sodium chloride + Water
D. Copper sulphate + Zinc→ Zinc sulphate + Copper

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Mouse liver cells were homogenized and the homogenate subjected to equilibrium density-gradient centrifugation with sucrose gradients. fractions obtained from these gradients were assayed for marker molecules (i.e., molecules that are limited to specific organelles). the results of these assays are shown in the figure. the marker molecules have the following functions: cytochrome oxidase is an enzyme involved in the process by which atp is formed in the complete aerobic degradation of glucose or fatty acids; ribosomal rna forms part of the protein-synthesizing ribosomes; catalase catalyzes decomposition of hydrogen peroxide; acid phosphatase hydrolysis monophosphoric esters at acid ph; cytidylyltransferase is involved in phospholipid biosynthesis; and amino acid permease aids in transport of amino acids across membranes. a) name the marker molecule and give the number of the fraction that is most enriched for each of the following cell components: lysosomes; peroxisomes; mitochondria; plasma membrane; rough endoplasmic reticulum; smooth endoplasmic reticulum.

Which of these best describes what occurs during cytokinesis? a) the chromosomes are separated b) the cell begins to divide by replicating the chromosomes c) the cytoplasm is divided between the two new daughter cells d) the nucleus opens to allow the chromosomes to enter the cytoplasm

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone