Indicate if the given direction of lymph flow is correct or incorrect. a) lymphatic capillaries to collecting vessels b) lymph nodes to lymph capillaries c) collecting vessels to lymphatic trunks d) collecting ducts to collecting vessels e) thoracic duct to cisterna chyli f) right subclavian trunk to thoracic duct g) intestinal trunk to right lymphatic duct h) left lumbar trunk to thoracic duct i) lower extremity lymph to thoracic duct j) right head lymph to thoracic duct

A) Lymphatic capillaries to collecting vessels -Correct

B) Lymph nodes to lymph capillaries - Incorrect

C) Collecting vessels to lymphatic trunks- Correct  

D) Collecting ducts to collecting vessels- Incorrect  

E) Thoracic duct to cisterna chyli - Incorrect

F) Right sub-clavian trunk to thoracic duct - Incorrect

G) Intestinal trunk to right lymphatic duct - Incorrect  

H) Left lumbar trunk to thoracic duct - Correct

I) Lower extremity lymph to thoracic duct - Correct  

J) Right head lymph to thoracic duct - Incorrect

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.