WBR0601

Author	[[PageAuthor::Ayokunle Olubaniyi, M.B,B.S [1]]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Physiology
Sub Category	SubCategory::Endocrine
Prompt	[[Prompt::A 58 year old woman with recently diagnosed type 2 diabetes mellitus comes to the clinic for a follow-up on her blood glucose. Her fasting blood sugar today is 4.5 mmol/l and she is doing well on diet and exercise. You decided to further educate her on the physiology of insulin. Which of the following requires insulin for glucose uptake?]]
Answer A	AnswerA::Brain cells
Answer A Explanation	AnswerAExp::Brain cells take up glucose through the activity of GLUT-1 (Glucose Transporter-1)
Answer B	AnswerB::Liver cells
Answer B Explanation	AnswerBExp::Liver cells make use of GLUT-2
Answer C	AnswerC::Skeletal muscle
Answer C Explanation	AnswerCExp::Skeletal muscle contains GLUT-4 but they require the action of insulin for glucose uptake
Answer D	AnswerD::Kidney
Answer D Explanation	AnswerDExp::Kidneys contain GLUT-4 for uptake of glucose
Answer E	AnswerE::Red blood cells
Answer E Explanation	AnswerEExp::Red blood cells contain GLUT-4 for glucose uptake
Right Answer	RightAnswer::C
Explanation	[[Explanation::Insulin is an anabolic hormone produced in the beta cells of the pancreas. It is involved in numerous processes in the body such as fatty acid synthesis, protein synthesis, and glucose metabolism. In glucose metabolism, insulin is needed in the transport of glucose into cells in skeletal muscle and adipose tissue. Some organs e.g., brain, RBCs, intestine, cornea, kidney, liver, and beta islet cells do not require insulin action for glucose uptake. Glucose transporters are required for uptake of glucose into many organs. There are 4 subtypes: GLUT-1 – RBCs, brain cells GLUT-2 - Renal tubular cells, small intestinal epithelial cells, liver cells and pancreatic beta cells GLUT-3 – Neurons, placenta GLUT-4 – Skeletal muscle, adipose tissue Educational Objective: Insulin aids in glucose uptake in skeletal muscles and adipose tissues. References: First Aid 2014 page 308]]
Approved	Approved::No
Keyword	WBRKeyword::Insulin, WBRKeyword::glucose transporters, WBRKeyword::glucose uptake
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::