.    Copy and complete the sentences using these words ( some may be used twice) Oxygen,   body tissues.   ,   left lungs,     carbon dioxide,      veins.   Deoxygenated ,    right. Oxygen*

The right side of the mammalian heart pumps blood to the   .   Here it absorbs and is now called   blood.

The gas   is removed from the blood in the lungs.   The blood returns to the   side of the heart and from here it is pumped to the where it gives up its   and is now called blood.    It passes back to the   side of the heart in     

                                                                                                                                                                    [8marks]

2.   Explain what is meant by the term single Circulation and double circulation.                   [4marks]

3. Write at least 4 key points / statements about the mammalian heart.                                  [8marks]

Identify which gland in the endocrine system is involved in each dysfunction and explain the effect of hormonal imbalance that was observed. 1.dwarfism 2.gigantism 3.goiter

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.

How does the nervous system affect the excretory system?