Circulatory Systems and Fluid Systems in the Body
38 Questions
1 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of the Blood Vascular System in the body?

  • To maintain blood pressure
  • To facilitate the movement of cerebrospinal fluid
  • To regulate body temperature
  • To transport oxygen and nutrients to cells and remove waste products (correct)

    • Which of the following fluid systems is responsible for the transportation of materials to cells and the removal of waste products?

  • Lymphatic System
  • Cerebrospinal Fluid
  • Blood Vascular System (correct)
  • Interstitial Fluid

    • What is the characteristic of closed circulatory systems?

  • Blood is circulated through a system of capillaries
  • Blood flows through a network of open arteries
  • Blood is pumped to the tissues in closed arteries without a venous return
  • Blood never leaves the vessels (correct)

    • Which of the following is an example of an open circulatory system?

    <p>Arthropods</p> Signup and view all the answers

    What is the main function of capillaries in the circulatory system?

    <p>To facilitate the exchange of fluids and nutrients</p> Signup and view all the answers

    How do the blood vessels in mammals grade into each other?

    <p>Smoothly and gradually</p> Signup and view all the answers

    What is the main function of the vasa vasorum?

    <p>To supply the connective tissue of the large vessel</p> Signup and view all the answers

    What is the characteristic of the Intima layer in veins?

    <p>Layer of endothelium and few layers of smooth muscle</p> Signup and view all the answers

    What is the number of fluid systems in the body?

    <p>5</p> Signup and view all the answers

    Which of the following is NOT a function of the blood system?

    <p>Regulation of body temperature</p> Signup and view all the answers

    What is the approximate thickness of capillaries?

    <p>8-10μm</p> Signup and view all the answers

    What is the estimated number of capillaries in the human body?

    <p>10 billion</p> Signup and view all the answers

    What is the purpose of precapillary sphincters?

    <p>To close off the circulation to the capillary bed</p> Signup and view all the answers

    What is the percentage of blood volume that is in the capillaries at any time?

    <p>5%</p> Signup and view all the answers

    What is the term for direct connections between the arterial and venous sides?

    <p>Arterio-venous anastomoses</p> Signup and view all the answers

    What is the characteristic of blood flow through the capillary beds?

    <p>Intermittent flow</p> Signup and view all the answers

    What is the primary function of vasomotion in the capillary beds?

    <p>To autoregulate oxygen levels in local tissues</p> Signup and view all the answers

    What is the approximate percentage of solids in plasma?

    <p>8%</p> Signup and view all the answers

    What is the main difference between the blood volume of males and females?

    <p>The difference in blood volume is related to body weight</p> Signup and view all the answers

    What is the function of the precapillary sphincters in the capillary beds?

    <p>To control the flow of blood into the capillaries</p> Signup and view all the answers

    What is the percentage of protein in plasma?

    <p>7%</p> Signup and view all the answers

    What is the term for the fluid that surrounds the cells of a given tissue?

    <p>Interstitial fluid</p> Signup and view all the answers

    What is the result of decreased oxygen levels in local tissues on the smooth muscle?

    <p>Relaxation</p> Signup and view all the answers

    What is the term for the rhythmic contraction and relaxation of the precapillary sphincters?

    <p>Vasomotion</p> Signup and view all the answers

    What is the net filtration pressure at the arterial end of a capillary?

    <p>8.3 mmHg</p> Signup and view all the answers

    What percentage of plasma passing through the capillaries is lost as a result of net filtration?

    <p>2%</p> Signup and view all the answers

    What is the direction of fluid movement when the pressure sign is positive?

    <p>Fluid leaves the location</p> Signup and view all the answers

    What is the estimated diffusion rate for the entire body capillary network?

    <p>240 litres/minute</p> Signup and view all the answers

    What is the net loss of fluid as a percentage of total volume that passes into the Lymphatic system?

    <p>10%</p> Signup and view all the answers

    What is the purpose of the negative interstitial fluid pressure?

    <p>To create a force for fluid to enter the tissue</p> Signup and view all the answers

    What is the primary process for trans-capillary exchange of solutes and solvents?

    <p>Diffusion</p> Signup and view all the answers

    What is the direction of fluid movement in the lymphatic system?

    <p>From tissue to lymphatic system</p> Signup and view all the answers

    What is the primary reason why most proteins cannot escape the capillary?

    <p>Because of the size of the pores in the capillary wall</p> Signup and view all the answers

    What is the net effect of the interstitial fluid pressure and interstitial fluid colloid osmotic pressure on fluid exchange?

    <p>They suck fluid out of the capillary</p> Signup and view all the answers

    What is the primary mechanism by which some proteins leave the capillary?

    <p>Through the process of pinocytosis</p> Signup and view all the answers

    What is the direction of fluid movement due to the capillary hydrostatic pressure?

    <p>Out of the capillary</p> Signup and view all the answers

    What is the primary force that pulls fluid back into the capillary?

    <p>Plasma colloid osmotic pressure</p> Signup and view all the answers

    What is the term for the filtration and absorption of fluid across the capillary wall?

    <p>Fluid exchange</p> Signup and view all the answers

    Study Notes

    Circulatory Systems

    • There are two types of circulatory systems: open and closed systems
    • Open systems: the heart pumps blood to the tissues in closed arteries, without a venous return (e.g., in Arthropods)
    • Closed systems: blood never leaves the vessels (e.g., in humans)

    Fluid Systems in the Body

    • There are five fluid systems in the body:
      • Blood Vascular System
      • Lymphatic System
      • Cerebrospinal Fluid
      • Coelomic/Peritoneal Fluid
      • Interstitial Fluid

    Blood Vascular System

    • The main functions of the blood system are:
      • Transportation of materials necessary for cell metabolism and synthesis
      • Transportation of waste products of cell activity
    • Oxygen and nutrients must be supplied to the cells, and carbon dioxide and nitrogenous wastes removed

    Blood Vessels

    • Blood vessels are divided into arteries, capillaries, and veins
    • Arteries, veins, and capillaries grade smoothly into each other
    • Vasa vasorum: small blood vessels in the wall of a large vessel that supply the connective tissue and then drain back into the main vessel

    Veins

    • Histology:
      • Intima: endothelium and a few layers of smooth muscle
      • Media: a few layers of smooth muscle
      • Adventitia: the largest layer with longitudinally arranged thick collagen fibers
    • Both large arteries and veins have their own blood supply called the vasa vasorum

    Capillary Networks

    • Capillaries are the smallest vessels, formed of a single layer of endothelial cells, 8-10μm thick, without smooth muscle
    • Estimated 10 billion capillaries in the body, rare for any cell to be more than 20-30μm from a capillary
    • Capillaries tend to be arranged in capillary beds, with only about 5% of blood volume in the capillaries at any time
    • Blood leaves the metarteriole and enters the capillary bed via precapillary sphincters, which can close off the circulation to the capillary bed

    Capillary Dynamics

    • Blood does not flow continuously through the capillary beds; in most organs, only a small number of capillaries are filled
    • Direct connections called preferential channels or arterio-venous anastomoses shunt blood rapidly from the arterial to venous side
    • Vasomotion: rhythmic myogenic activity of contraction and relaxation of the precapillary sphincters, affecting the entrance to the capillaries

    Physiology - Capillary Dynamics

    • Few cells are in direct contact with the capillaries; most cells obtain their nutrient and oxygen requirements via the interstitial fluid
    • The blood volume is about 8% body weight, with a difference in blood volume between males and females related to body weight
    • Red blood cells in a capillary

    Physiology - Fluid Exchange

    • Fluid exchange in the capillary bed involves four pressures:
      • Capillary hydrostatic pressure (25 mmHg)
      • Plasma colloid osmotic pressure (28 mmHg)
      • Interstitial fluid pressure (-6.3 mmHg)
      • Interstitial fluid colloid osmotic pressure (5 mmHg)
    • Net filtration pressure (tendency for plasma to leave the blood at the arterial end of a capillary) = 8.3 mmHg
    • Net body filtration rate = 1.7-3.5 ml/min or 2.5-5.0 liters/day
    • Diffusion occurs in both directions and is estimated for the entire body capillary network at 240 liters/minute

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Learn about the types of circulatory systems, including open and closed systems, and explore the five fluid systems in the human body.

    More Like This

    Exploring Human Anatomy and Physiology
    12 questions

    Exploring Human Anatomy and Physiology

    SaintlyPascal avatar
    SaintlyPascal
    Human Circulatory System
    12 questions

    Human Circulatory System

    LongLastingWilliamsite4241 avatar
    LongLastingWilliamsite4241
    Circulatory System Basics
    10 questions

    Circulatory System Basics

    CommendableSpruce avatar
    CommendableSpruce
    Circulatory System Basics
    16 questions

    Circulatory System Basics

    DeadOnCottonPlant avatar
    DeadOnCottonPlant
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser