Unit 4: Animals Flashcards
1
Q
Definition: Diffusion
A
Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration.
2
Q
Definition: Single-Celled Organisms
A
In single-celled organisms, diffusion allows direct exchange with the environment, facilitating nutrient uptake and waste removal.
3
Q
Definition: Cell Membrane
A
All substances must pass through the cell membrane to enter or exit the cell, maintaining a controlled internal environment.
4
Q
Definition: Interstitial Fluid
A
This fluid surrounds all cells, facilitating the exchange of nutrients and wastes.
5
Q
Why is diffusion inadequate for transporting chemicals through thick bodies like humans?
A
The time it takes for diffusion increases exponentially with distance.
6
Q
Which organs are primarily involved in the diffusion of gases, nutrients, and wastes in multicellular organisms?
A
Lungs, intestines, kidneys
7
Q
Nutrient and Waste Exchange: Definition: Capillary Transport
A
Oxygen-rich blood is transported to body tissues via small capillaries.
8
Q
Nutrient and Waste Exchange: Definition: Exchange Process
A
Oxygen diffuses from blood to interstitial fluid, while waste products and carbon dioxide move from interstitial fluid to blood.
9
Q
Nutrient and Waste Exchange: Definition: Efficient Exchange
A
By ensuring short diffusion distances, the body maintains efficient nutrient delivery and waste removal.
10
Q
Nutrient and Waste Exchange: Definition: Circulatory Function
A
Frequent circulation of blood through exchange organs helps maintain homeostasis.
11
Q
What must surround every living cell to allow substances to permeate the membrane?
A
Water
12
Q
In the context of diffusion, what is meant by the term “internal pond”?
A
The water that surrounds the external environment of the cell.
13
Q
Definition: The Circulatory System
A
System that transports nutrients, blood, and waste around the body.
14
Q
Definition: Plasma
A
The liquid part of the blood, making up about 55% of its volume. It contains water, proteins, glucose, hormones, and waste products.
15
Q
Definition: Red Blood Cells (RBCs)
A
Cells that carry oxygen from the lungs to the body and bring carbon dioxide back to the lungs to be expelled.
16
Q
Definition: White Blood Cells (WBCs)
A
Cells involved in immune response, defending the body against infection and disease.
17
Q
Definition: Platelets
A
Small cell fragments that play a key role in blood clotting and wound healing.
18
Q
Functions of Blood: Transportation
A
Carries oxygen, nutrients, hormones, and waste products to and from cells.
19
Q
Functions of Blood: Regulation
A
Helps regulate body temperature, pH levels, and fluid balance.
20
Q
Functions of Blood: Protection
A
Contains immune cells that protect against pathogens and has clotting factors to prevent excessive bleeding.
21
Q
Definition: Arteries
A
Thick-walled vessels that carry blood away from the heart under high pressure. They branch into smaller arterioles and eventually capillaries.
22
Q
Definition: Veins
A
Thinner-walled vessels that carry blood toward the heart under lower pressure. They have valves to prevent backflow.
23
Q
Definition: Capillaries
A
The smallest blood vessels where the exchange of gases, nutrients, and waste occurs between blood and tissues.
24
Q
Which vessels carry blood away from the heart?
A
Arteries
25
What prevents blood from slipping backward on the compression stroke of the heart?
Valves
26
Heart: Definition
The human heart is a cone-shaped organ, roughly the size of a fist.
27
Heart: Location
Positioned beneath the sternum, slightly to the left.
28
Heart: Pericardium
Double-layered sac enclosing the heart, with fluid between layers, allowing smooth movement during heartbeats.
29
What is the primary function of the pericardium sac surrounding the heart?
To enable the layers to slide over each other during heartbeats.
30
Anatomy of the Heart: Structure
The heart is a muscular organ divided into four chambers: two atria and two ventricles.
31
Anatomy of the Heart: Right Atrium and Ventricle
Receive deoxygenated blood and pump it to the lungs.
32
Anatomy of the Heart: Left Atrium and Ventricle
Receive oxygenated blood from the lungs and pump it to the body.
33
Anatomy of the Heart: Valves
Ensure one-way blood flow through the heart, preventing backflow.
34
Blood Flow Through the Heart: Right Side
Blood enters the right atrium via the superior and inferior vena cava.
35
Blood Flow Through the Heart: Left Side
Returns from the lungs via the pulmonary veins to the left atrium.
36
What is the main function of the atria in the heart?
Receive blood returning to the heart.
37
Definition:Pulmonary Arteries
Carry deoxygenated blood to the lungs.
38
Definition: Pulmonary Veins
Return oxygenated blood from the lungs.
39
Definition: Aorta
Distributes oxygenated blood to the body.
40
Definition: Tricuspid Valve
Between right atrium and right ventricle.
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Definition: Pulmonary Valve
Between right ventricle and pulmonary artery.
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Definition: Mitral Valve
Between left atrium and left ventricle.
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Definition: Aortic Valve
Between left ventricle and aorta.
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Definition: Systemic Circulation
Blood flow from the heart to the body and back.
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Definition: Pulmonary Circulation
Blood flow from the heart to the lungs and back.
45
Definition: Cycle
Describes how blood is oxygenated in the lungs and distributed to the body.
46
Definition: Oxygenation
Blood picks up oxygen and releases carbon dioxide in the lungs.
47
Definition: Distribution
Oxygenated blood is sent throughout the body to deliver oxygen to tissues.
48
What is the primary function of the SA node in the heart?
To regulate the heart rate.
49
Which blood vessels bring blood to the heart from the general body circulation?
Superior and inferior vena cavas.
50
Definition: Heart Cycle
The heart cycle consists of systole (contraction) and diastole (relaxation).
51
Definition: Systole
Contraction phase
52
Definition: Diastole
53
Heart Sounds: Mechanism
Sounds from valve closures.
54
Heart Sounds: Types
'Lub' (atrioventricular) and 'Dupp' (semilunar)
55
Definition: Valve Dysfunction
Abnormal sounds from defective valves.
56
Definition: SA Node
Acts as the heart's natural pacemaker.
57
Definition: AV Node
Delays impulse to ensure full atrial emptying.
58
Factors Affecting Heart Rate
Nervous System Control: Two nerve pathways regulate rate.
Hormonal Influence: Epinephrine increases heart rate.
Temperature: Increase in temperature raises heart rate.
Exercise: Raises heart rate due to increased carbon dioxide.
59
Definition: Electrocardiograms (ECG)
A graphical representation of the electrical activity of the heart over time.
60
Blood Vessels: Connective Tissue
Outer layer with elastic fibers allowing flexibility.
61
Blood Vessels: Smooth Muscle
Middle layer, thicker in arteries, with elastic properties.
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Blood Vessels: Endothelium
Inner lining, thin and smooth, facilitating blood flow.
63
Velocity of Blood Flow: Capillary Bed
Blood flow slows as it enters capillaries despite narrower size.
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Velocity of Blood Flow: Total Cross-Sectional Area
Capillaries have larger total area, facilitating exchange of materials with interstitial fluid.
65
Velocity of Blood Flow: Leisurely Flow
Slower blood flow in capillaries aids in efficient nutrient and waste exchange.
66
Pressure in Blood Vessels: Blood Pressure
Force exerted by blood against vessel walls, measured as blood pressure.
67
Pressure in Blood Vessels: Arterial Pressure
Greater due to forceful contraction of ventricles during systole.
68
Pressure in Blood Vessels: Capillary Role
Capillaries act as bottlenecks, contributing to pressure surge during heart contraction.
69
Pressure in Blood Vessels: Arterial Thickness
Arteries are thicker to withstand high pressure during systole.
70
Pressure in Blood Vessels: Venous Pressure
Drops to zero due to resistance in small arteries and capillaries.
71
Pressure in Blood Vessels: Effects of Stress
Physical and emotional stress can elevate blood pressure by constricting blood vessels.
72
Blood Return Mechanism: Muscular Contraction
Veins are surrounded by muscles that contract during body movement, aiding blood flow.
73
Blood Return Mechanism: One-Way Valves
Veins contain valves allowing blood flow only towards the heart, preventing backflow.
74
Definition: Capillary Gas Exchange
The circulatory system's most vital role is facilitating the exchange of materials between blood and interstitial fluid, which nourishes and supports cellular functions.
75
Fluid Dynamics: Arteriole End
Higher hydrostatic pressure facilitates the outward flow of fluids.
76
Fluid Dynamics: Venous End
Reduced hydrostatic pressure and increased osmotic pressure favor fluid re-entry.
77
Fluid Dynamics: Fluid Recovery
Approximately 99% of the fluid expelled at the arterial end re-enters at the venous end; the remaining 1% is returned to the blood via the lymphatic system.
78
Lymphatic Dysfunction: Edema
Cause: Accumulation of interstitial fluid due to inadequate lymphatic drainage.
Result: Tissues become swollen and bloated.
79
Lymphatic Dysfunction: Elephantiasis
Cause: Parasitic worms block lymph vessels, preventing fluid return.
Result: Severe swelling due to trapped fluids.
80
Lymphatic Dysfunction: Protein Deficiency
Cause: During prolonged hunger, the body depletes blood proteins, lowering osmotic pressure.
Result: Fluids accumulate in tissues, leading to conditions like a bloated belly.
81
Skeletal Muscles: Movement of Lymph
Like veins, lymphatic vessels rely on skeletal muscle movement to propel lymph through the system.
82
Skeletal Muscles: Muscle Contraction
Regular body movements help lymph flow against gravity.
83
Atherosclerosis: Understanding, Treatment, and Prevention
Atherosclerosis is a cardiovascular disease. Begins with injury to the endothelial lining of arteries. Leads to plaque formation that narrows the artery.
84
Mechanism of Atherosclerosis
Injury often occurs at artery branch points.
Endothelial cells are lost, exposing smooth muscle.
Plaque forms as fat infiltrates the endothelial lining.
85
Atherosclerosis: Factors Contributing to Endothelial Injury
Interaction of arterial wall cells with various factors. Debate on the role of shear forces and blood flow. High cholesterol levels as a contributing factor.
86
Atherosclerosis: Response to Endothelial Loss
Small wounds are repaired by elongation of adjacent cells. Larger wounds require cell migration. Communication between cells is still under study.
87
Atherosclerosis: Plaque Formation and Artery Narrowing
Plaque growth narrows the artery lumen (inside space of a tubular structure, such as an artery or intestine). Reduced blood flow leads to more endothelial denudation (erosion). Vicious cycle of artery narrowing.
88
Treatments for Coronary Heart Disease
Bypass Surgery
Balloon Angioplasty
Laser Irradiation
89
Definition: Bypass Surgery
Developed in the 1960s, involves chest cavity opening. Grafting arteries from the legs to bypass blocked arteries. Alleviates angina (chest pain) by restoring blood flow.
90
Definition: Balloon Angioplasty
Less invasive than bypass surgery. Uses a catheter with a balloon to compact plaque. Mixed results; can significantly improve blood flow.
91
Definition: Laser Irradiation
Uses lasers to destroy plaque. Converts plaque to a blood-soluble gas. Risks include accidental artery perforation.
92
What is the direct physiological event that leads to the development of atherosclerosis?
Injury to the endothelial lining of arteries.
93
Which of the following is NOT a common treatment for coronary heart disease?
Appendectomy
94
How does balloon angioplasty work to treat atherosclerosis?
Balloon angioplasty involves inserting a catheter with a small balloon into the affected artery. Once the plaque is reached, the balloon is inflated, compressing the plaque and widening the artery to improve blood flow.
95
Definition: Cellular Respiration
ATP generation in cells, requiring oxygen, occurs in mitochondria.
96
Definition: Organismal Respiration
Breathing, taking in oxygen and expelling carbon dioxide.
97
What is the function of respiration?
Makes oxygen gas available to the cells where it is needed and to remove carbon dioxide gas from the cells to the outside of the body.
98
What animal uses air sacs for respiration?
Birds
99
Functions: Nasal cavity and Sinuses
Warms incoming air via blood vessels. Filters dust using nasal hairs and mucus. Humidifies air through mucus lining.
100
Functions: Upper Pharynx
Extends from the nasal cavity to the uvula. Contains Eustachian tube openings. Houses two sets of tonsils.
101
Functions: Middle Pharynx
Extends from uvula to epiglottis. Shared passageway for food, water, and air.
102
Functions: Lower Pharynx
Extends from the epiglottis to the larynx and esophagus. Connects to both respiratory and digestive systems.
103
Functions: Larynx
Controls pitch through vocal cord tension. Located at the top of the trachea. Vocal cords vibrate to produce sound. Tension changes pitch during exhalation. Inflammation is known as laryngitis.
104
Function: Trachea
Supported by cartilage rings to stay open. Lined with cilia to brush debris out. Cilia damaged by smoking can regenerate if smoking stops.
105
Function: Lungs
bring oxygen into the lungs (inhalation). Provides continuous gas exchange between air breathed in and the blood in the pulmonary circulation, supplying oxygen and removing carbon dioxide. Clear carbon dioxide from the lungs (exhalation).
106
What is the main function of the lungs?
Bringing oxygen into the lungs (inhalation), providing continuous gas exchange between air breathed in and the blood in the pulmonary circulation, supplying oxygen and removing carbon dioxide.
107
Where is the site of the gas exchange?
Alveoli
108
Gas Exchange Process
Oxygen diffuses from alveoli into blood. Carbon dioxide diffuses from the blood into the alveoli. Alveolar walls and capillary walls are extremely thin for efficient gas exchange.
109
Mechanism of Breathing
The diaphragm contracts increases thoracic volume, and air is drawn into the lungs. The diaphragm relaxes, decreases thoracic volume, air is expelled from the lungs. Ribs and intercostal muscles assist in breathing during exertion.
110
Respiratory Disorders: Cystic Fibrosis
The genetic disease causes thick mucus in the lungs. High risk of infection due to mucus buildup. No cure, but treatment focuses on managing symptoms and slowing progression.
111
Respiratory Disorders: Pneumonia
Inflammation of the lungs caused by infection. Symptoms: chest pain, fever, coughing. Treatment may include antibiotics.
112
Respiratory Disorders: Tuberculosis
Chronic bacterial infection primarily affects the lungs. Stages: exposure, infection, active disease. Treatment is long-term but effective.
113
Respiratory Disorders: Lung Cancer
Starts in the bronchi, and varies by type (e.g., non-small cell, small cell). Symptoms: cough, chest pain, shortness of breath. Smoking is the leading cause.
114
Common Respiratory Illnesses: Cold and Flu
Cold: caused by over 200 viruses, mild symptoms. Flu: severe respiratory illness, caused by influenza viruses. Preventive measures: vaccines, hygiene.
115
Definition: Digestive System
Allows nutrients to access the circulatory system and body cells. Humans require nutrients to be broken down into simple molecules before absorption.
116
Which of the following statements accurately describes the digestive system of an amoeba?
A) Amoebas have a complex digestive system with specialized organs.
B) Amoebas engulf food particles through a process called phagocytosis and digest them in food vacuoles.
C) Amoebas use external enzymes to break down food particles before ingestion.
D) Amoebas have a gastrointestinal tract similar to that of higher organisms.
B) Amoebas engulf food particles through a process called phagocytosis and digest them in food vacuoles.
117
Definition: The Alimentary Canal
The alimentary canal, also known as the digestive system or food tube, is a complex pathway for the digestion and absorption of food.
118
Definition: Mouth
The mouth is the starting point of digestion, where mechanical breakdown begins.
119
Function: Upper Esophageal Sphincter
Opens during swallowing to direct food into the esophagus, avoiding the larynx.
120
Function: Lower Esophageal Sphincter
Prevents air entry from the oral cavity and stomach content reflux when closed.
121
Function: Stomach
The stomach churns food and mixes it with gastric juices to form chyme.
122
Definition: Gastric Pits
Pockets or indentations in the stomach mucosal lining that contain specialized secretory cells that secrete mucus, gastric juice components, and digestive hormones.
123
What is the primary function of a gastric pit in the stomach?
To secrete digestive enzymes and gastric juice.
124
Function: Small Intestine
Site for enzymatic digestion to form absorbable molecules. Absorption of virtually all nutrients from the diet, including amino acids, monosaccharides, lipids as well as water and electrolytes. Most absorption occurs through epithelium covering villi.
125
Function: Large Intestine
Water and electrolyte absorption (recovery of remaining 10% water). Formation and storage of feces (75% water, 25% solids, bacteria, undigested matter). Fermentation by microbes (breakdown of indigestible molecules, production of vitamins K and B-12, gases like hydrogen and methane).
126
Which of the following is NOT a function of the small intestine?
A) Absorption of nutrients and minerals from food.
B) Production of bile for fat digestion.
C) Mixing and propulsion of food using peristalsis.
D) Secretion of digestive enzymes to aid in food breakdown.
B) Production of bile for fat digestion.
127
What is chyme and where is it primarily found?
A semi-liquid mixture of partially digested food and digestive juices, found in the stomach and small intestine.
128
What organ has the role of 1. producing enzymes to break down proteins, fats, and carbohydrates and 2. neutralizing stomach acid in the duodenum?
Pancreas
129
Definition: Macronutrients
Carbohydrates, fats, and proteins are essential for energy, growth, repair, and reproduction.
130
Definition: Micronutrients
Vitamins and minerals are needed in smaller amounts but are vital for various bodily functions.
131
Function: Nutrients
Nutrients provide the body with energy, support growth, repair tissues, and aid in various metabolic processes. They are essential for maintaining bodily functions and overall well-being.
