study group bn ap1 l1 pptx(1)

BN Study Group 2012-2013 Anatomy / Physiology Lesson 1

Teaching AssistantsKeith Li Isabella Wong

3943-1236 3943-1253keithkyli@cuhk.edu.hk isabella@cuhk.edu.hk

Statement

• The Study Group aims to help you understand basic concepts.

• Sample questions will be provided and discussed, but they do NOT in any way imply that our explanation are orthodox.

• We do NOT know any future exam questions.• We do NOT know any answer keys of the subjects,

past or future. • It depends on YOUR understanding and revision to

get good grades.

Anatomy

Anatomy

• Cells and tissues• Arteries and Veins• Lymphatics

On Exam Question Design

• Previous exams: – “Write a paragraph on…”– “Describe the arterial supply / venous drainage of…”– Each 25 marks

• Exam in 2010:– Short Q with a/b parts, 6+4, 5+5 etc.– Each 10 marks– ↓ Rote memory– ↑ Understanding & articulation

• What you need to do– Identify what is important, know where to pay attention

Sample Questions – Cells and Tissues

• Name the precursor cell that give rise to connective tissues. Also give four cell types and corresponding classes of connective tissues that the precursor cell is capable of forming. (25)

Precursor

Sample Questions – Cells and Tissues

• Compare and contrast stratified cuboidal epithelium and transitional epithelium in terms of their structure, function and location in the body.

• Describe the characteristic features of transitional epithelium and where they are found in the human body.

Function

Location

Structure

Function

Location

Structure

MCQ – Cells and tissues (1/10)

• Which of the following epithelial tissue has a single layer of square-shaped cells?A. Pseudostratified columnar epithelium.B. Ciliated simple columnar epithelium.C. Simple cuboidal epithelium.D. Stratified cuboidal epithelium.

MCQ – Cells and tissues (2/10)

• Which of the following is not a function of simple epithelium?A. Protection.B. Secretion.C. Absorption.D. Filtration.

MCQ – Cells and tissues (3/10)

• What is the primary function of transitional epithelium?A. Absorption.B. Stretch.C. Secretion.D. Protection.

MCQ – Cells and tissues (4/10)

• Which fibres ensure that connective tissue is strong and tough?A. Collagen fibres.B. Reticular fibres.C. Elastic fibres.D. Plasma fibres.

MCQ – Cells and tissues (5/10)

• Which of the following connective tissues is found in heart valves?A. Areolar tissue.B. Dense irregular connective tissue.C. Dense regular connective tissue.D. Reticular tissue.

MCQ – Cells and tissues (6/10)

• Which of the following statements on cartilage is true?A. Fibrocartilage contains the most elastic fibres.B. Hyaline cartilage is found within the ears.C. Elastic cartilage is the most abundant in the

human body.D. The weakest cartilage tissue is hyaline cartilage.

MCQ – Cells and tissues (7/10)

• Blood is an example of _____ connective tissue.A. Liquid.B. Loose.C. Avascular.D. Dense.

MCQ – Cells and tissues (8/10)

• Which of the following areas does not contain mucous membrane?A. The urinary tract.B. The respiratory system.C. The pericardium.D. The digestive tract.

MCQ – Cells and tissues (9/10)

• Smooth muscle is both:A. Involuntary and striated.B. Involuntary and non-striated.C. Voluntary and striated.D. Voluntary and non-striated.

MCQ – Cells and tissues (10/10)

• Scar tissue is generated by:A. Fibroblasts.B. Osteoclasts.C. Stem cells.D. Parenchymal cells.

• Describe the arterial supply of the cardiac muscles. (12.5)

• Describe the venous drainage of the cardiac muscles. (25)

• a) Describe the arterial supply and venous drainage of the heart muscle. (6)

Sample Questions – Blood supply

Note the difference in style!

Sample Questions – Blood supply

• b) Describe TWO structural defects in the heart that may lead to oxygen-rich blood mixed with oxygen-poor blood in the chambers. (4)

Sample Questions – Blood supply

• Write short notes on the following: – b) Auscultatory areas of the tricuspid, mitral,

aortic and pulmonary valves. (4)

tricuspid mitrial

pulmonaryaortic

Sample Questions – Blood supply

• Write a short paragraph describing the arterial supply of the upper extremities. (25)

Sample Questions – Blood supply

• Briefly describe the origin of the celiac trunk and name the organs that it supplies. (25)

Sample Questions – Blood supply

• Describe the possible cause and symptoms of portal hypertension. (6)

• Write a short paragraph describing the hepatic portal circulation. (25)

Sample Questions – Blood supply

• Write a short paragraph describing the arterial supply of the lower limb, commencing from the heart. (25)

• Describe the veins supplying the lower limbs.

Sample Questions – Blood supply

• Describe the venous drainage of the brain. (25)

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Sample Questions – Lymphatics

• Write short notes on TWO major lymphatic ducts. (4)

Break?

Physiology

Topics

• Homeostasis, Thermoregulation• Action potential• Skeletal muscle contraction• Conduction of the heart, Cardiac muscle• Heart rate & BP, Microcirculation

Homeostasis

Homeostasis

• Mostly MCQ• E.g.

– What is the most effective mechanism for reducing/increasing heat loss?

– Where are the receptors for body temperature regulation?

Pre-optic area of hypothalamus

Action potential and Neurotransmission

Neurotransmission

• Most relevant questions are MC.• Have a clear concept of

– How an action potential is triggered– The use of myelin sheath– Chemical transmission at synapses and NMJs

Na+ channel opened Na+ channel inactivatedK+ channel opened

Locally, there are influx of Na+ and efflux of K+.Na+/K+ pump is used to restore the resting potential.

This slide is animated.

Myelin sheath

Neuromuscular junction (NMJ) and Muscle contraction

AP at NMJCa2+ enters, activate kinaseKinase activate other downstream proteinsAch vesicles on presynaptic membrane Docking on membrane Release Ach

Kinase = enzyme that releases phosphate in function

Sample Final Exam Questions – Muscle contraction

• Give 2 reasons why ATP is important in the relaxation phase of skeletal muscle contraction. Name the pathway where ATP can be built up and stored when a muscle is at rest.

• Describe the 3 uses of ATP in the contraction-relaxation mechanism of skeletal muscle.

• A. Define a motor unit. (1 mark)B. Give 2 functions of ATP in skeletal muscle contraction and relaxation. (4 marks)

Motor unit

• A motor neuron and all muscles fibers it innervates

接

拉放

ATP kinase on myosin head

Conformational change

Ca2+ returns to SR

Ca2+ released from SR, binds to troponin and expose active

sitesby

Sample Final Exam Questions – Muscle contraction

• Describe why calcium ion is an important regulator in skeletal muscle contraction. What is the major source of calcium ion in skeletal muscle?

• Answers can be found in the following video

Video viewing

• Action potential at NMJ – http://www.youtube.com/watch?v=70DyJwwFnkU (02:18)– http

://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter10/animation__action_potentials_and_muscle_contraction.html

• Muscle contraction – http://www.youtube.com/watch?v=gJ309LfHQ3M (00:58)

• Synaptic transmission (watch yourselves) – http://www.sumanasinc.com/webcontent/animations/content/synaptictrans

mission.html

• Breakdown of ATP and Cross-Bridge Movement During Muscle Contraction– http

://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter10/animation__breakdown_of_atp_and_cross-bridge_movement_during_muscle_contraction.html

MCQ – Nerves & NMJ (1/5)

• Which neurotransmitter is associated with the neuromuscular junction?A. Dopamine.B. Norepinephrine.C. Acetylcholine.D. CSF.

MCQ – Nerves & NMJ (2/5)

• Nerves that carry impulses away from the central nervous system are:A. Afferent nerves.B. Efferent nerves.C. Motor nerves.D. Mixed nerves.

MCQ – Nerves & NMJ (3/5)

• Which of the following statement is NOT true of skeletal muscle?A. Is under voluntary control.B. Is not striated.C. Can have long muscle fibres.D. Is usually attached to the skeleton.

MCQ – Nerves & NMJ (4/5)

• The energy for muscle contraction is most directly obtained from:A. Aerobic respiration.B. Phosphocreatinine.C. Anaerobic respiration.D. ATP.

MCQ – Nerves & NMJ (5/5)

• If additional ATP is required, which of the following can be used as an alternative energy source?A. Myosin.B. Troponin.C. Creatine phosphate.D. Myoglobin.

Cardiac physiology

Sample Final Exam Questions – Cardiac muscle

• Draw a ventricular muscle cell action potential. Describe the changes in membrane permeability that underlies the potential changes.

Ventricular muscle cell action potential

Sample Final Exam Questions – Cardiac conduction

• Write short notes on the conducting system of the heart.

• Hints: – Signal initiation? – Direction of travel?– Nodes?– Bundles?– Compartments?

ECG

P

Q

R

S

S

T: Repolarization

Note this is NOT depiction of action potential of individual cell.+ve/-ve is related to direction of travel.

Test your understanding: Where on the ECG does atrial and ventricular contractions occur?

ECG animations

• http://www.rnceus.com/ekg/lead.gif

• http://upload.wikimedia.org/wikipedia/commons/e/e5/ECG_principle_slow.gif

Spontaneous depolarization

• All heart cells can do this• Na+ channels open as

soon as MP<threshold• K+ channels close• Easy to get more +ve easy to reach threshold another AP fired spontaneous depolarization

• SA node is the fastest and suppresses other tissues

Sample Final Exam Questions – Cardiac output

• Describe the preload of the Frank-Starling Law of the heart.

Preload

• Preload – Stretch of the heart before contraction. If the muscle walls of the heart are stretched prior to a stroke then they will squeeze harder on the stroke. To get a greater stretch more blood must be in the heart. This observation is called the ‘Frank-Starling law of the heart’.

• Preload ↑, Cardiac output ↑• 橡筋拉得越緊 , 回彈力越大

Contractility

• Contractility - The contractility of the heart is influenced by inotropic agents that make it pump either stronger or weaker. Positive inotropic agents such as Calcium ions and adrenaline make it pump stronger, negative inotropic agents such as potassium ions make the stroke weaker.

• Contractility ↑, Cardiac output ↑

Afterload

• Afterload – Pressure needed to get blood out. In order to get blood out the heart the back-pressure in the blood vessels must be overcome. The harder it is to get blood out, the less blood will actually leave the heart. You can imagine if the blood vessels are clogged or narrow that this will make things harder.

• Afterload is a measure of required pressure,an indirect indicator of vessel resistance.Afterload ↑, Cardiac output ↓

• 橡筋彈穿一張廁紙 vs 彈穿一張 A4 紙彈穿 A4 紙的 afterload 較大

Sample Final Exam Questions – Cardiac output

• Explain why stroke volume is related to venous return. Give a few ways where venous return can be improved in a normal healthy adult.

• Venous return ↑ Preload ↑ Stoke volume ↑

• To improve venous return: Contraction of limb muscles, inhalation, lying down, etc.

For your interest only

• http://www.ann.com.au/MedSci/blood.htm

• Norton, J. M. (2001). Toward consistent definitions for preload and afterload. Advances in Physiology Education, 25: 53-61.http://advan.physiology.org/cgi/content/full/25/1/53

Sample Final Exam Questions – Cardiac output

• Describe the importance of a baroreflex when a person suffers a drop in blood pressure.

• Describe how baroreceptor reflex works in the regulation of blood pressure.

• Define hypertension and write short notes on baroreceptor reflex in blood pressure control.

90

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Baroreceptor reflex

• Carotid sinus baroreceptor頸動脈 竇 壓力 感受器 Glossopharyngeal nerve / Vagus nerve 舌 咽 神經 / 迷走 神經 Cardioregulatory & vasomotor centres 心臟 調節 及 血管運動 中心 Sympathetic / Parasympathetic nerves 交 感 / 副 交 感 神經

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Sample Final Exam Questions – Circulation

• What are the major sites of resistance in the systemic vascular system? Give one function of this site? Give two examples of local or hormonal factors that can alter resistance of the systemic vascular system.

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Major sites of resistanceThe smaller the vessel radius,

the greater is the resistance血管半徑越小 , 阻力越大

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Local and hormonal control of BP

95

MCQ – Cardiac (1/5)

• Which heart chamber has the thickest muscle wall?A. Right ventricle.B. Right atrium.C. Left ventricle.D. Left atrium.

MCQ – Cardiac (2/5)

• The contraction of a heart chamber is known as:A. Automaticity.B. Diastole.C. Isovulmetric.D. Systole.

MCQ – Cardiac (3/5)

• Normal electrical excitation of the heart begins in:A. The bundle of His.B. The purkinje fibres.C. The atrioventricular node.D. The sinoatrial node.

MCQ – Cardiac (4/5)

• The effect of increased parasympathetic nervous system activity is to:A. Increase heart rate.B. Decrease heart rate.C. Increase force of contraction.D. Decrease force of contraction.

MCQ – Cardiac (5/5)

• Preload is mostly a factor of:A. End systolic volume.B. End diastolic volume.C. The Frank-Starling law.D. Adrenaline release.

MCQ sources

• Peate, I., & Nair, M. (Eds.). (2011). Fundamentals of anatomy and physiology for student nurses. Chichester, UK: Wiley-Blackwell.

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The End.