SNC 2DI – Biology Unit Test Review #2

Tissues, Medical Imaging Technology, and Organ Systems

(ANSWER KEY)

Tissues:

  1. Define the terms Cell Specialization and Cell Differentiation and explain the difference between the two.

Cell Specialization is the process in which cells take on specific functions within a multicellular organism. Cell differentiation is a stage of development which a living organism experiences during which specialized cells form.

  1. Define the term Stem Cell and explain the difference between totipotent, pluripotent, and adult stem cells.

Stem Cell: an unspecialized cell that can produce various specialized cells.

Totipotent stem cells occur early in the development of a human embryo and can become any kind of cell.

Pluripotent stem cells arise as the embryo continues to develop and are less versatile than totipotent stem cells.

Adult stems cells arise late in embryonic development and are only capable of producing specific types of cells.

  1. What are embryonic stem cells?

Embryonic stem cells are those found in young embryos and include totipotent and pluripotent stem cells.

  1. What are the four types of tissues in the human body? List and describe the function of each type.

Epithelial Tissue / Muscle Tissue / Nervous Tissue / Connective Tissue
Lines the surfaces of the body and between organs. Made of cells with strong connections between adjoining cell membranes. Form a barrier / Designed to change shape to allow for movement. Works by shortening and lengthening. / Made up of neurons which send and receive signals. Coordinate actions of the body. / Strengthens, supports, protects, binds, or connects cells and tissues.
  1. What are the two types of epithelial tissue? Describe their appearance and explain their function.

Skin Epithelia / Columnar Epithelia
Thin, flat cells that form sheets.
Functions as a semi-permeable barrier between external and internal environment. / Columns of cells forming a barrier.
Found in small intestine, stomach, glands
May secrete mucus, have cilia, and or absorb materials
  1. What are the three types of muscle tissue? Describe their appearance and explain their function.

Skeletal Muscle / Smooth Muscle / Cardiac Muscle
Cells lined up in the same direction appearing striped or striated.
Found throughout the body providing support and attaching to bone allowing movement. / Cells that taper at both ends and appear striated.
Found in blood vessels, walls of internal organs. Contracts slower than skeletal muscle but can sustain action longer. / Cells branched and appear striated with nuclei that appear to be between cells. Contract as a single unit. Found only in the heart.
  1. Describe the appearance and explain the function of nervous tissue.

The nervous tissue appear to have finger-like projections and function to relay signals from the brain or spinal cord to the muscles and glands or to detect information about their environment and trigger a response.

  1. What are the three types of connective tissue? Describe their appearance and explain their function.

Bone / Fat (adipose tissue) / Blood
Cells surrounded by calcium hardened tissue containing blood vessels. Needed for movement, provide support, provide protection. / Large, tightly packed cells. Found under skin and around organs acting as insulation and padding. Also a storage molecule for energy. / Red blood cells, white blood cells, platelets, and plasma. Transports nutrients and oxygen to cells. Removes wastes and carbon dioxide from cells. Clots to seal cuts and attacks invading bacteria and viruses.
  1. Identify each of the following types of tissue.


______Nervous______/ ______Bone______

______Smooth Muscle______/
_____Fat (Adipose Tissue)____

______Skin Epithelia______

Medical Imaging Technologies:

  1. Create a table to organize the four medical imaging technologies we discussed (x-rays, CT/CAT scan, Ultrasound, and MRI) and their functions. Describe the image formed by each technology.

X-Ray / Transmits electromagnetic (x-ray) radiation through the body exposing the x-ray film on the other side.
Best used for imaging hard tissue such as bone.
CT/CAT (Computerized Axial Tomography) / Produces very thin “slices” of a body part using x-rays. These images are then reconstructed into a three-dimensional image using a computer.
Can be used to produce 3D images of all types of tissue.
Ultrasound (Medical Sonography) / Uses high-frequency sound waves which are recorded using a microphone attached to a computer. The computer uses this information to generate and image of the area. Used to show real-time movement of body parts. Useful for watching organ function.
MRI (Magnetic Resonance Imaging) / Uses radio signals projected into a magnetic field to create images of body parts.
Can be used to produce images of all types of tissue.

Organ Systems:

  1. Make a list of the 11 organ systems found in the human body.

Circulatory, Digestive, Respiratory, Excretory, Immune, Muscular, Endocrine, Reproductive, Integumentary, Nervous, Skeletal.

  1. Create a table summarizing the main functions of each organ system.

Organ System / Function
Circulatory / Transports blood, nutrients, gases, and wastes
Digestive / Takes in food and breaks it down. Absorbs nutrients. Removes solid wastes from the body.
Respiratory / Controls breathing. Exchanges gases in lungs.
Excretory / Removes liquid wastes from the body.
Immune / Defends the body against infections.
Muscular / Works with the bones to allow for movement
Endocrine / Produces and releases hormones which act as signalling molecules to keep the body systems in balance.
Reproductive / Includes the reproductive organs for producing offspring
Integumentary / Skin, hair, and nails which create a waterproof barrier around the body.
Nervous / Detects changes in the environment, signalling the brain and spinal cord, which then trigger a response.
Skeletal / Supports, protects, and works with muscles to move parts of the body
  1. Explain how the circulatory and digestive systems are interconnected.

The circulatory system is responsible for transporting the nutrients absorbed by the digestive system throughout the body where they will be used to generate energy for movement, grow, repair, etc.

  1. Explain how the circulatory and respiratory systems are interconnected.

The circulatory system is responsible for transporting oxygen to cells while bringing waste carbon dioxide to the lungs while the respiratory system is responsible for breathing and gas exchange bringing fresh oxygen to the body and removing carbon dioxide.

  1. Digestive System:
  2. What are the four functions of the digestive system?

Ingestion, Digestion, Absorption, Elimination

  1. Which organs are considered accessory organs of the digestive system? Why are the called accessory organs?

The Liver, Gall Bladder, Pancreas, and Salivary Glands. They are considered accessory as the produce enzymes and chemicals critical to digestion but are not part of the digestive tract.

  1. All of the organs through which food travels are collectively referred to as what?

The Digestive Tract

  1. List in order, starting from the oral cavity and ending at the anus, the organs of the digestive tract.

Oral Cavity  Pharynx  Esophagus  Stomach  Small Intestine  Large Intestine  Rectum  Anus.

  1. What are the two types of digestion? In which areas of the digestive tract do each occur?

Physical (Mechanical) / Chemical
Mouth (teeth/tongue) , esophagus (peristalsis), stomach (churning), intestines (peristalsis) / Mouth (saliva), Stomach (Acid + Enzymes), Small Intestine (Bile + Enzymes)
  1. Provide one example of an enzyme responsible for the breakdown of carbohydrates. Where is this enzyme found? (Hint: there is only one you needed to know)

Salivary Amylase is found in the mouth and breaks down carbohydrates.

  1. Provide one example of an enzyme responsible for the breakdown of proteins. Where is this enzyme found? (Hint: there is only one you needed to know)

Pepsin is found in the stomach and begins the digestions of fats.

  1. The ball of food formed in the mouth by the tongue is known as the what?

The Bolus

  1. What macronutrient is broken down into small droplets by bile? Where does this process occur?

Fats (lipids) are broken down into small droplets by bile in the duodenum of the small intestine.

  1. Where is bile produced? Where is it stored? How does it get to the duodenum?

Bile is produced in the liver, stored in the gall bladder, and delivered to the duodenum via the bile duct.

  1. What is bicarbonate? Where is it produced? What is its role in digestion?

Bicarbonate is a chemical produced in the pancreas which neutralizes the acidic chyme entering the small intestine from the stomach.

  1. The first 1 m of the small intestine is known as what?

The Duodenum

  1. What is the primary function of the small intestine?

The absorption of nutrients

  1. Draw a sketch of villi including the capillaries. How does this relationship between the circulatory system and digestive system improve nutrient absorption?

The capillaries of the circulatory system are brought very close to the surface of the intestinal lining where nutrients are absorbed into the blood stream. The villi act to increase surface area and allow for greater nutrient absorption

  1. What is the primary function of the large intestine?

Absorption of water

  1. What is peristalsis?

Peristalsis is the rhythmic muscle contractions which push food through the digestive tract.

  1. Create a list of the organs and structures indicated on the diagram.(DON’T LOOK AT YOUR NOTES FIRST!)

1. Teeth, 2. Epiglottis, 3. Liver, 4. Gall bladder, 5. Bile duct, 6. Large intestine, 7. Appendix, 8. Salivary gland, 9. Tongue, 10. Esophagus, 11. Stomach, 12. Duodenum, 13. Pancreas, 14. Small intestine, 15. Rectum/anus

  1. Respiratory System:
  2. What is the primary function of the respiratory system?

To control breathing allowing for gas exchange to occur in the lungs.

  1. During a process known as __Gas Exchange__, oxygen diffuses into the capillaries and __Carbon Dioxide__ diffuses out of the capillaries into the __Alveoli__.
  2. Diffusion occurs because substances want to move from an area of __High__ concentration to an area of __Low__ concentration.
  3. Describe how foreign material is trapped and removed from the respiratory system.

Mucous coating the nasal cavity and trachea trap foreign material and cilia work to sweep the material out of the respiratory system.

  1. Which of the lungs has 2 lobes? Why is this the case? How many lobes does the other lung have?

The left lungs has two lobes to allow room for the heart in the chest cavity. The right lung has 3 lobes.

  1. What are the functions of the nasal cavity? Does the oral cavity accomplish the same functions?

The nasal cavity functions to warm, moisten, and filter air. The oral cavity is also able to warm and moisten air although not as effectively. The oral cavity is not able to filter air.

  1. Why is it important to have an epiglottis?

It is important to have an epiglottis as the flap of elastic cartilage acts to prevent food entering the trachea by covering the opening to the larynx when food is swallowed.

  1. Make a list, in anatomical order, of the structures of the respiratory system which are supported by cartilage.

Larynx  Trachea  Bronchi

  1. What happens when the diaphragm contracts? Relaxes?

Contracts = Inhale

Relax = Exhale

  1. Explain what happens to the volume and pressure in the chest cavity during contraction and relaxation of the diaphragm.

When the diaphragm contracts it moves down causing the chest cavity volume to increase and the pressure to decrease. This draws air into the lungs.

When the diaphragm relaxes it pushes up into the chest cavity, reducing the volume of the chest cavity and increasing the pressure. This pushes air out of the lungs.

  1. What are the three types of bronchi? How are they different from one another?

Primary  Secondary  Tertiary. Primary air the largest in diameter and tertiary are the smallest (of the bronchi! Bronchioles are smaller of course).

  1. Create a list of the organs and structures indicated on the diagram. (DON’T LOOK AT YOUR NOTES FIRST!)

1. Nose/Nasal Cavity, 2. Oral Cavity (Mouth), 3. Pharynx, 4. Epiglottis, 5. Larynx, 6. Trachea, 7. Bronchi, 8. Bronchioles, 9. Diaphragm, 10. Alveoli, 11. Capillaries

  1. Circulatory System:
  2. What are the three main parts of the circulatory system?

The heart, the blood, and the blood vessels.

  1. What four functions does the circulatory system accomplish?

Regulates body temperature by dilation and constriction of blood vessels, fight against infections (white blood cells), transports hormones to target tissues (e.g. insulin), transports appropriate gases and substances to and from the body’s cells (O2, CO2, nutrients).

  1. What are the four main components of blood?

Red blood cells, white blood cells, platelets, and plasma.

  1. What do red blood cells contain that allow them to carry oxygen?

Hemoglobin

  1. What percentage of the bloods volume is comprised of red blood cells? Why is it so high?

Almost half of the blood volume is red blood cells. As these cells are responsible for transporting oxygen to all of the body tissues we require them in high numbers to keep all tissues oxygenated.

  1. Which component of blood is responsible for clotting? What percentage of the blood volume does this comprise?

Platelets are responsible for clotting. They comprise less than 1% of the blood volume.

  1. When we get invaded by bacteria and viruses we rely on the actions of which blood component to make us better?

White blood cells

  1. In order to keep blood volume up and blood flowing almost half of our blood is made up of what blood component?

Plasma

  1. What are the three types of blood vessels?

Arteries, Veins, and Capillaries

  1. Arteries carry blood Away from / Towards (circle one) the heart, whereas veins carry blood Away from / Towards the heart.
  2. Arteries branch into smaller __Arterioles__, whereas veins branch into smaller __Venules__.
  3. Why do arteries have the thickest walls? Why do capillaries have the thinnest walls?

Arteries have the thickest walls because the blood pressure is highest in the arteries. Capillaries have the thinnest walls to allow for absorption of nutrients and diffusion of gases.

  1. The heart is made up of which three types of tissue?

Cardiac Muscle, Nervous Tissue, and Connective Tissue

  1. What Four valves can be found in the heart? What is their function?

The left and right AV valves as well as the pulmonary valve and the aortic valve. These valves control the flow of blood through the chambers of the heart and prevent blood from flowing backwards.

  1. What two veins carry blood from the upper and lower body back to the heart?

The superior and inferior vena cava.

  1. Blood destined for the body tissues leaves the heart via which blood vessel?

The Aorta

  1. Blood destined for the lungs leaves the heart via which blood vessel? Which blood vessel returns blood from the lungs to the heart?

The Pulmonary Artery. The Pulmonary Vein

  1. Chart the flow of blood for one complete circuit through the circulatory system starting in the left ventricle. (Try charting the flow from different locations!)

Left Ventricle  Aorta  Body Tissues  Superior/Inferior Vena Cava  Right Atrium  Right Ventricle  Pulmonary Artery  Lungs  Pulmonary Vein  Left Atrium  Left Ventricle

  1. Create a list of the organs and structures indicated on the diagram. (DON’T LOOK AT YOUR NOTES FIRST!)

1. Aorta, 2. Superior Vena Cava, 3. Pulmonary Artery, 4. Pulmonary Veins, 5. Right Atrium, 6. Right AV Valve, 7. Right Ventricle, 8. Inferior Vena Cava, 9. Pulmonary Artery, 10. Pulmonary Veins, 11. Left Atrium, 12. Left AV Valve, 13. Aortic Valve, 14. Left Ventricle, 14. Aorta