Test 4 Flashcards
Describe a closed circulatory system.
Requires vessels to contain fluids that circulate around organism.
Describe an open circulatory system.
Does not require vessels to contain fluids that circulate around organism.
What are the 7 functions of a vertebrate’s circulatory system?
- Transport O2 from lungs to tissues; CO2 from tissues to lungs
- Distribute nutrients from digestive system to body’s cells
- Transport waste and toxic substances to liver, where many are detoxified, and to kidneys for excretion
- Distribute hormones from organs to tissues on which they act
- Regulate body temperature, achieved partly by adjustments in blood flow
- Prevent blood loss with clotting mechanism
- Protect body from bacteria and viruses by circulating antibodies and white blood cells
What is blood made of?
Hematocrit (37 to 47% for dudes, 42 to 52% for women), Buffy Coat (small %), and Plasma (remaining percent)
Which of the following organisms typically possess an open circulatory system?
-Birds
-mammals
-fish
-insects
Insects
What is plasma made of?
Water, proteins, nutrients, hormones, etc.
What is Buffy Coat made of?
White blood cells and platelets
What is hematocrit made of?
Red blood cells
Which component of blood makes up the largest portion of its volume and carries nutrients, hormones, and waste products?
Plasma
What are the 5 key differences between arteries and veins?
- Viens are oblong while arteries are circular.
- Arteries are under much more pressure than veins.
- The arteries have many layers of smooth muscle and connective tissue and the veins have very few layers
- Arteries have several elastic layers and veins have few elastic layers
- Arteries have a much smaller lumen (open space) than veins.
Explain how veins in the venous system work.
Calf muscles act as a pump for deep leg veins, contraction of calf muscles causes blood flow and valves prevent backflow
Which of the following is a main component of the circulatory system responsible for exchanging nutrients, gasses, and waste products between the blood and body tissues?
capillaries
Which of the following is a main component of the circulatory system responsible for carrying oxygen-poor blood from the body back to the heart?
Veins
Describe the structure and function of arteries.
Arteries have thick walls and carry oxygen-poor blood from the heart to the lungs.
Describe the structure and function of capillaries.
Capillaries have thin walls and allow for the exchange of oxygen, nutrients, and waste products between the blood and surrounding tissues.
Describe the sequence of events during a complete cardiac cycle of blood circulation.
Atria contract, ventricles relax, blood enters atria, atria relax, ventricles contract, blood is pumped out of the heart
Which of the following chambers of the heart pumps oxygenated blood to the rest of the body during the cardiac cycle?
Left ventricle
Which of the following sequences correctly represents the flow of blood through the circulatory system?
- Arteries → Capillaries → Veins
- Veins → Capillaries → Arteries
- Veins → Arteries → Capillaries
- Capillaries → Veins → Arteries
Arteries → Capillaries → Veins
Which blood vessel carries oxygen-rich blood from the lungs back to the heart?
Pulmonary Veins
Describe the circulation of blood through the heart.
Superior and inferior Vena Cava → the Right Atrium →(through tricuspid valve) to right ventricle→(through pulmonary valve) to pulmonary artery→ to lungs→ to left atrium → (through mitral valve) to left ventricle→ (through aortic valve) to aorta → to rest of body
What are the two types of valves?
Atrioventricular & semilunar valves
What do atrioventricular valves do?
Maintain unidirectional blood flow between atria & ventricles (Tricuspid = on right, Bicuspid/ mitral = left)
What do semilunar valves do?
Ensure one-way flow out of ventricles to arterial systems (Pulmonary valve at the exit of the right ventricle, aortic at the exit of the left ventricle)
What is the average heart rate?
120/80
How long does a cardiac cycle take
0.8 seconds
Where does the conduction system start in the heart?
The Sinoatrial node
Describe how electricity travels through the heart
Starts at the Sinoatrial node (above the right atrium wall) to the Atrioventricular node down to the Purkinje fibers
What is a PQRST wave?
the record of electrical activity from an electrocardiogram
What part of the cardiac cycle does the P wave show?
Depolarization/ contraction of atrium
What part of the cardiac cycle does the QRS wave show?
Depolarization/contraction of the ventricle
What part of the cardiac cycle does the T wave show?
Repolarization/relaxation of ventricles
What is the location and function of the mitral valve in the heart?
It is located between the left atrium and left ventricle, preventing the backflow of blood from the left ventricle to the left atrium.
What is the function and location of the pulmonary valve in the heart?
It is located between the right ventricle and the pulmonary artery, preventing the backflow of blood from the pulmonary artery to the right ventricle.
What is systole in the context of the cardiac cycle?
It is the contraction phase of the heart chambers.
What is diastole in the context of the cardiac cycle?
It is the relaxation phase of the heart chambers.
What are the 2 types of digestion and give an example for each.
- Mechanical (Mastication (mouth), Peristalsis (Esophagus), Maceration (Stomach), Segmentation (small intestine))
- Chemical (Swallowing (saliva), The stomach (HCl acid), and Enzymes)
What does saliva do when swallowing?
- Helps prevent desiccation in the mouth
- Helps prevent cavities
- Coat food
- With tongue, help form a bolus
What digestive processes occur in the stomach?
-Longitudinal, oblique, circular muscles that churn predigested food ( takes 1-2 hours and mixes food with gastric juices to make chyme)
- HCl acid
What is pepsinogen?
the inactive form of pepsin
What is Pepsin?
The active form of the enzyme that breaks protein down into polypeptides
What is the role of hydrochloric acid in gastric juice?
It activates the enzyme pepsinogen into pepsin.
what % of food digestion occurs in the small intestine
90%
What are the roles of the duodenum?
-Protein Digestion
-Emulsification / Breakdown of fat globules into tiny droplets, which provides a larger surface area on which the enzyme pancreatic lipase can act to digest the fats into fatty acids and glycerol. Emulsification assisted by the action of the bile salts
What are microvilli?
Brush border on the wall of small intestine to increase surface area for absorption
What accounts for 90% of water absorption?
Large intestine
What does the Cecum do?
a “dead-end pouch” that contains bacteria
What does the appendix do?
vestigial organ, possibly a bacteria garden
what is feces made of?
undigested material: 60% bacteria, mucus, cellulose (bulk flow)
Where does the digestion of carbohydrates start?
Starts in the mouth with salivary amylase
Where does the digestion of proteins start?
Starts in stomach with pepsin (enzyme)
Where does the digestion of lipids occur?
Fat in the small intestine produces hormones that
release pancreatic lipase (from the pancreas) and bile (produced in the liver, stored in the gallbladder), bile salts help emulsify/break down fat globules into fatty acids that can be absorbed in the small intestine (duodenum).
What does fiber help?
bulk flow
What is the primary function of the small intestine?
Absorption of nutrients from digested food
What is the main function of the large intestine?
Absorption of water and electrolytes
Describe cirrhosis of the liver.
Cirrhosis is a disorder characterized by the gradual replacement of healthy liver tissue with scar tissue, leading to impaired liver function.
What is the primary cause of type 2 diabetes?
Insulin resistance resulting from lifestyle factors and obesity
What are some adaptations that fungi have for feeding?
- Substrate feeding
- absorptive feeding
- Extracellular digestion
- secrete enzymes and store surplus nutrients like animals
What is a suspension/filter feeder?
capture and ingestion of food particles that are suspended in water.
What are some examples of suspension feeders?
whale and clams
What are substrate feeders?
Live in food sources and eat as they burrow (leaf miners, maggots).
What are deposit feeders?
Eat their way through dirt, picking up decayed organic material (earthworms).
What are fluid feeders?
Suck nutrient-rich fluids. Can be from a host (parasites: mosquitoes, aphids) or flowers (pollinators: (bees, wasps, hummingbirds)
What are bulk feeders?
Eat large pieces of food using adaptations such as claws, teeth, pinchers, fangs, etc.
What are Phagotrophs?
feeds by ingesting organisms or organic particles, which are digested within its body
What are Osmotrophs?
obtains its nutrients by absorbing organic matter in solution from its surroundings.
What are mixotrophs?
not only use energy from the sun to take up nutrients and grow but they can also kill and eat other plankton
What is phagocytosis?
The process by which a cell (often a phagocyte or a protist) engulfs a solid particle to form an internal compartment known as a phagosome
What is Pinocytosis?
mode of endocytosis in which small particles are bought into the cell, forming an invagination, and then suspended within small vesicles
What is the function of the xylem?
Water and nutrients from roots to different parts of the plant. “WXYZ” (thin-walled)
What is the function of the Phloem?
Organic compounds from photosynthesis sites to other parts of the plant. “Food flows”
What is the difference between a dicot and monocot plant vascular tissue?
In a dicot system vascular tissue is in bundles and arranged around the periphery. In a monocot system, vascular bundles are scattered throughout the ground tissue.
Describe Translocation.
Sucrose from source cells into companion cells
Then into sieve-tube elements.
This reduces water, which causes water to enter the phloem from the xylem.
The resulting positive pressure forces the sucrose-water mixture down toward the roots
What is Transpiration?
causes water to return to the leaves through the xylem.
What are stomata?
Openings on the bottom of the leaf allow plants to take up CO2 and release water vapor and oxygen
What is cohesion-tension theory?
The sun’s energy indirectly powers transpiration, water is cohesive due to hydrogen bonding, tension exerted on water by evaporation at plant’s surface pulls a continuous stream of water from the soil
What is guttation?
Exudation of drops of xylem sap on tips/edges of leaves of some vascular plants (grasses, some fungi).