MMED1007 Revision

What is the purpose of fixing tissue?

To prevent tissue breakdown by microorganisms and endogenous enzymes

Resolution is defined as:

The minimum distance over which two objects can be distinguished from a single object

Going from smallest to largest, which of the following has the items in the correct order?

Molecules, organelles, cells, tissues, organs

Which of the following organelles are bounded by one or more phospholipid membranes?

Endosomes, lysosomes and Golgi apparatus

Smooth muscle cells have lengths that range from (and to):

From 0.1mm to 1mm

Which of the following is incorrect about smooth muscle cells?

Smooth muscle cells usually contract faster than striated muscle cells

Which of the following is true about all nerve cells in the human body

All nerve cells can release one or more neurotransmitters

Which of the following is FALSE about the bladder epithelium?

The cells on the luminal surface of the bladder epithelium are columnar in shape

Which is true about the lamina propria?

It contains numerous lymphocytes

Starting at the end nearest the mouth (proximal) and progressing distally, which is the correct order of organs of the gastrointestinal tract:

Oesophagus, stomach, small intestine, colon

Which of the following is NOT a role for hepatocytes:

Production of digestive amylase

The crypts of Lieberkuhn are NOT burial places for suspected vampires in an obscure part of Eastern Europe. They are best described as:

Glandular structures at the base of the villi, located within the mucosa

Which is the correct order of filtrate flow in the kidney corpuscles and tubules?

Bowman's capsule, proximal convoluted tubules, distal convoluted tubules, collecting ducts

Which cells in the kidney produce renin?

Juxtaglomerular cells

External urethral sphincter is exclusively innervated by:

Somatic pudendal nerves

The ureters have several basic layers of tissue. Which is the correct order of these layers starting at the luminal surface?

Urothelium, lamina propria, muscularis, adventitia

What is the approximate surface area of the respiratory exchange airways in a healthy adult human?

60-75 square metres

The lungs are highly distensible and can be readily stretched by forces applied to their surface. When these forces are removed, the lung "recoils". What is the major component of the lung tissue that causes this distensibility and recoil?

Elastin fibres

The walls of the larger airways are stiffened by which material?

Hyaline cartilage

Which structures are always located at the bottom of cilia?

Basal bodies

Parathyroid hormone is synthesised in:

Principal cells

Which of the thyroid hormones (T) listed has the greatest biological activity?

T3

Aldosterone is mainly synthesised and secreted by:

Zona glomerulosa

A tumour causing the corticotrophs of the anterior pituitary to be more active would cause high blood levels mainly of:

Corticosteroids

In erythrocytes, the protein spectrin provides the cell with the ability to:

Change shape

Which one of the following statements is CORRECT?

Neutrophils are also known as polymorphonuclear leukocytes

Choose the path that a red blood cell takes through the listed blood vessels, if it started from the left ventricle and ended in the right atrium?

Elastic artery, muscular artery, arteriole, capillary, venule, medium-sized vein, large vein

Which type of blood vessel often has both circularly and longitudinally oriented smooth muscle?

Large veins

Which heart structure receives blood from the pulmonary veins?

Left atrium

Purkinje fibres are distinct from contractile cardiac muscle cells in that they:

Are larger in size.

What is a lymph node follicle?

A site for germinal centre formation

The outer cortex of lymph nodes contains predominantly:

B lymphocytes

With respect to the statements below, indicate the INCORRECT statement. Skeletal muscle fibres:

Are separated from each other by epimysium.

With respect to skeletal muscle function, which one of the following is CORRECT?

Skeletal muscle is responsible for voluntary movement.

In regard to elastic fibres, which of the following statements is INCORRECT?

They are present in abundance in ligaments and tendons.

Which cells ARE NOT normally found in loose connective tissue?

Monocytes, platelets

With respect to "cartilage", which one of the following statements is CORRECT?

Cartilage is avascular

Osteoclasts:

Are multinucleated, giant cells that resorb bone matrix

Which of the following is not composed mostly of keratin and keratin-related molecules?

Cartilage

The finger-like projections of the dermis into the epidermis, that increase the surface area of contact between the layers, are most commonly called:

Dermal papillae

Neurons can be classified on the basis of their structure; the major types of neurons distinguished in this way include:

Unipolar, bipolar, multipolar, pseudounipolar and anaxonic

Which of the following best describes the meaning of the word "ganglia"?:

They are cluster of nerve cells in the periphery

The central nervous system (CNS) consists of the following regions:

The Cerebrum, Cerebellum, Brain Stem and Spinal Cord

Which of the following statements is correct. The gray matter of the spinal cord:

Contains abundant astrocytes and large neuronal cell bodies, especially those of motor neurons in the ventral horns

The layers of the retina, visible with H&E, are:

Choroid, rods and cones, outer nuclear, outer plexiform, inner nuclear, inner plexiform, ganglionic, nerve fibre

Crystallins are:

Proteins filling the cytoplasm of differentiating lens fibres

The stapedius muscle is the smallest muscle in the body and plays an important role in protecting the ear against loud noise. It does this by pulling on a structure and dampening its movement. Which structure:

It connects to the stapes ossicle

The tympanic membrane separates

Separates the external auditory meatus (ear canal) from the middle ear

Stains are used primarily for what purpose in microscopy?

To help distinguish some parts of the specimen from surrounding regions

What is the device called that is used to cut thin sections for light microscopy from tissue embedded in a paraffin wax block?

A microtome

Which is generally true of high power objectives on a microscope compared to lower power objectives

A high power objective is usually physically longer

In haematoxylin and eosin (H&E) staining, which of the following is true?

Haematoxylin stains nucleic acids well

Which of the following has this combination of features: they are a component of the cytoskeleton, they are formed from smaller molecules jointed together to make long structure which are about 25nm in diameter and are associated with dynein and kinesin?

Microtubules

Which of the following is INCORRECT about actin microfilaments?

They are about 6.5 um (microns) in diameter

Haematoxylin is widely used as a histological stain. What structures does it tend to bind to and stain most intensely?

Nuclei and rough endoplasmic reticulum

Misfolded or damaged proteins represent a considerable hazard to the long term health of cells. These are usually disposed of by:

Being broken down in proteasomes

Within a single striated muscle cell, there are numerous rod-like structures that contain the thick and thin filaments. These are called "myofibrils". Which of the following is closest to the diameter of a myofibril? (um= micrometres, nm=nanometres)

1-2um

The three major types of fibres in connective tissue are:

Collagen, elastin and reticulin

Cardiac myocytes (heart muscle cells) have nuclei that distinguish them from those of smooth and striated muscle. Which of the following best describes the nuclei of cardiac myocytes

They are round nuclei, usually in the middle of fibres, often surrounded by other sub-cellular structures such as mitochondria, glycogen granules

The cells that "insulate" nerve cell axons outside the central nervous system, and which cause their action potentials to propagate more rapidly than would otherwise be the case are called:

Schwann cells

Which of the following is true about chemical synapses?

There is always a gap between pre- and post-synaptic membranes

Which of the following is FALSE about simple squamous epithelia?

They consist of several layers of squamous cells

Starting near the luminal surface (ie; from the mucosa) and going outwards towards the serosa, which describes the order of the layers of smooth muscle and enteric nervous plexuses correctly?

(i) submucous plexus, (ii) circular muscle of muscularis externa, (iii) myenteric plexus, (iv) longitudinal muscle of muscularis externa

The entire gut wall is comprised of 4 basic layers of tissue (within which there are sub-layers). Starting at the luminal surface (ie: the centre of the gut) and progressing outwards, which is the correct order and identity of these 4 basic layers?

Mucosa, submucosa, muscularis externa, serosa

The muscularis externa has to propel swallowed material, which may be quite viscous and difficult to push. Which best describes the arrangement of the muscularis externa of the human oesophagus?

It is mostly striated muscle for the upper third and mostly smooth muscle for the lower two thirds

Which of the following types of cell produces an exocrine secretion?

Goblet cells

Hepatocytes make up 80% of the cells in the liver. They are quite large cells with (on average) a diameter of:

20-30µm

A vessel in the portal triad has a lining of cuboidal epithelium. It is mostly likely:

A branch of a bile ductule

The surface epithelium of the colon is made up of:

Simple, columnar epithelium with some apical microvilli

Portal triads typically contain 3 vessels (although many also have a fourth lymph vessel which is not counted, for obscure reasons). Anyway, which of the following best describes the 3 vessels of the portal triad? Branches of:

The hepatic portal vein, hepatic artery and bile ductule

Which of the following is a major exocrine secretion of the liver?

Bile

Vasopressin released from the pituitary gland increases water reabsorption in the cells of the:

Collecting ducts

Blood in the renal interlobular arteries flows next into which vessels?

Afferent arterioles

The juxtaglomerular apparatus includes:

Juxtaglomerular cells, extraglomerular mesangial cells and macula densa

The capillary loop of the juxtamedullary nephrons is called the:

Vasa recta

The following cell types are not present in the bladder wall:

Skeletal muscle cells

Detrusor muscle of the bladder arranged in several sub-layers. Starting at the luminal surface they are as follows:

Muscularis mucosa, inner longitudinal, middle circular, outer longitudinal

The male urethra is composed of following segments starting at the internal urethral sphincter:

Prostatic urethra, membranous urethra, spongy urethra

The posterior pituitary is made up of:

Unmyelinated nerve fibres

A male patient presents with the following signs, large feet and hands, protruding jaw and above average height. What are the cells in the pituitary gland secreting excess hormone that may account for these symptoms?

Somatotrophs

Thyroid hormone is made and stored in:

Colloid

You notice on your holiday to a remote part of a country with poor nutrition that many people have a large bulge (goiter) in the area of the thyroid in their neck. What do you believe these people need to add to their diet to correct this abnormality?

Iodide

Cortisol is mainly synthesised and secreted by:

Zona fasciculata

The posterior pituitary:

Only secretes ADH and oxytocin, the hypothalamus is responsible for synthesising these hormones

Insulin is synthesised and secreted by:

Beta cells within the islet of Langerhans

Monocytes can be identified in a routine blood smear because they have a:

Kidney-shaped nucleus and no specific granules

Name the leukocytes that are also known as granulocytes.

Neutrophils, eosinophils and basophils

Name the leukocytes that are agranulocytes.

Lymphocytes and monocytes

Neutrophils can be identified in a routine blood smear because they have a:

Multi-lobed nucleus and light pink specific granules

What component of artery walls helps to drive blood through the arterial system?

Elastin

Moving through the arterial system from large arteries to small arteries, what do you expect to see in terms of the amount of smooth muscle cells?

An increase in the amount of smooth muscle cells

Which type of blood vessel is primarily involved in the control of the organ blood flow and mean arterial pressure?

Arterioles

Moving from arteries to veins, what changes would you likely see in the relative amounts of the three tunics?

Intima remains same; Media decreases in size; Adventitia increases in size

What cell type forms the lining of all blood vessels?

Endothelial cells

Where is the SA node located?

Right atrium

At an intercalated disc:

Two cardiac muscle cells are connected by gap junctions.

What structure provides the pathway for the movement of electrical current between the cells of the conduction pathway and the ventricular muscle fibers?

Gap junctions

Which statement regarding heart valves is CORRECT?

The middle layer is called the fibrosa.

Which one of the following best describes the movement of immune cells in the body?

Immune cells tend to circulate between the vasculature, lymphoid tissues and lymphatic vessels

What best describes the inflammatory response?

Is involved in tissue repair, is vital for clearance of pathogens, is involved in healing due to injury, can be acute or chronic