Nutrition, The Human Body Lecture #3
40 Questions
0 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

Which class of nutrients is considered energy-yielding and contains nitrogen?

  • Fats
  • Vitamins
  • Proteins (correct)
  • Carbohydrates

    • What role do vitamins play in the body?

  • Energy-yielding
  • Non-energy-yielding (correct)
  • Structural support
  • Storage of excess nutrients

    • Which nutrient class does not yield energy, yet is crucial for chemical reactions in the body?

  • Fats
  • Carbohydrates
  • Water (correct)
  • Proteins

    • What is the main source of calories in the human diet?

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

    How do excess nutrients primarily get stored in the body?

    <p>As glycogen and fat</p> Signup and view all the answers

    Which of the following nutrients is not considered essential?

    <p>Saturated fats</p> Signup and view all the answers

    What is the primary function of the nervous system in relation to nutrition?

    <p>Hormonal regulation</p> Signup and view all the answers

    How is energy from nutrients ultimately used by the body?

    <p>For functions, growth, and maintenance</p> Signup and view all the answers

    Which nutrient has a caloric value of 9 Cal/g?

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

    What is the circulatory exchange process responsible for?

    <p>Transport of body fluids and nutrients</p> Signup and view all the answers

    Which class of nutrient is primarily responsible for the breakdown of food into energy through chemical processes?

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

    What is the primary role of bile in the digestive system?

    <p>Emulsify fats</p> Signup and view all the answers

    What are villi and microvilli primarily responsible for in the small intestine?

    <p>Nutrient absorption</p> Signup and view all the answers

    How does the body primarily store excess carbohydrates?

    <p>In the liver as glycogen</p> Signup and view all the answers

    What is the role of the microbiota in the digestive system?

    <p>Facilitating digestion and absorption</p> Signup and view all the answers

    Which statement best describes the mechanism of peristalsis in the digestive system?

    <p>It involves coordinated muscle contractions to move food.</p> Signup and view all the answers

    The interaction between which two systems is crucial for regulating metabolism and digestion?

    <p>Nervous and endocrine systems</p> Signup and view all the answers

    Which of the following best describes phytochemicals?

    <p>Active compounds in plant-based foods with health benefits.</p> Signup and view all the answers

    What is chyme and where is it formed?

    <p>Fluid resulting from stomach digestion</p> Signup and view all the answers

    What is the primary role of enzymes in the human body?

    <p>To speed up specific chemical reactions.</p> Signup and view all the answers

    Which of the following substances primarily neutralizes stomach acid in the small intestine?

    <p>Pancreatic bicarbonate</p> Signup and view all the answers

    Which system is primarily responsible for the transportation of blood and its constituents?

    <p>Cardiovascular System</p> Signup and view all the answers

    What is the approximate transit time for food to pass through the digestive system?

    <p>24 hours</p> Signup and view all the answers

    How do genes influence the way the body handles nutrients?

    <p>They affect the enzymes produced and nutrient utilization.</p> Signup and view all the answers

    Which class of nutrients is primarily responsible for providing energy to the body?

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

    What is the concept of nutritional genomics primarily concerned with?

    <p>How nutrients affect gene activity and vice versa.</p> Signup and view all the answers

    Which body fluid is crucial for supplying energy, oxygen, and nutrients to the cells?

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

    What effect does the environment have on genetic expression according to epigenetics?

    <p>It modifies how genes are expressed without changing the DNA sequence.</p> Signup and view all the answers

    Which of the following statements is true regarding how excess nutrients are stored in the body?

    <p>Excess carbohydrates are stored as glycogen, fats as fat tissue.</p> Signup and view all the answers

    What is the relationship between the nervous system and the endocrine system in terms of nutrition?

    <p>They cooperate to regulate bodily functions, including metabolism.</p> Signup and view all the answers

    Which nutrient class is primarily responsible for energy storage in the body?

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

    Which role does the endocrine system predominantly play in digestion?

    <p>Regulating digestion through hormonal signals</p> Signup and view all the answers

    What effect does severe undernutrition have on the small intestine?

    <p>Causes the absorptive surface to shrink</p> Signup and view all the answers

    Which of the following is a key function of beneficial bacteria in the large intestine?

    <p>Fermenting indigestible fibers into SCFAs</p> Signup and view all the answers

    How does the nervous system influence appetite and digestion?

    <p>By coordinating muscle contractions during digestion</p> Signup and view all the answers

    Where does the human body primarily store excess carbohydrates?

    <p>Liver and muscles</p> Signup and view all the answers

    Which of the following statements about bile recycling is correct?

    <p>Bile is recycled and chemically altered to aid digestion.</p> Signup and view all the answers

    Which nutrients are produced through the fermentation process facilitated by gut microbiota?

    <p>Vitamin K2</p> Signup and view all the answers

    What mechanism allows the body tissues to exchange materials as body fluids circulate?

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

    What happens to specific enzymes during malnutrition?

    <p>They are downregulated, leading to impaired digestion.</p> Signup and view all the answers

    Study Notes

    Course Information

    • Course title: Introduction to Nutrition: Concepts & Controversies
    • Course code: EPHE 155
    • Institution: University of Victoria, School of Exercise Science, Physical and Health Education
    • Instructor: Dr. Kimberly McQueen, BSc ND
    • Email: [email protected]

    The Human Body

    • The human body is composed of trillions of cells
    • Cells are self-contained living entities
    • Cells need oxygen, energy sources (nutrients), and water to survive
    • Cells die at varying rates
    • The level of organization in the human body includes: cells → tissues → organs → body systems

    Cells

    • Cells have a membrane enclosing their contents
    • Nucleus contains hereditary material (genes)
    • Genes control characteristics and daily workings of the cell
    • Genes are copied when the cell duplicates
    • Instructions from genes translate into proteins performing functions
    • Mitochondria take in nutrients and release energy

    Genes

    • Genes provide the blueprint for body functions
    • Genes are short sections of DNA
    • An estimated 30,000 genes are in the Human Genome
    • Genes direct protein production, often enzymes
    • Genes provide instruction for the structural components of cells
    • Different genes are active in different cells
    • Genes are also impacted by nutrient status

    Enzymes

    • Enzymes are working proteins speeding up chemical reactions
    • Enzymes do not change during reactions

    Genetics

    • Individuals genetically differ
    • We inherit genes from parents, but subtle/non-subtle mutations can occur
    • Nutritional genomics studies how nutrients affect genes and vice versa
    • Epigenetics is the study of how behavior and environment impact gene expression

    Body Systems Supporting Digestion

    • Cardiovascular: delivers oxygen, nutrients to tissues, removes waste, and works with the digestive system
    • Endocrine: regulates digestion via hormones, such as insulin and glucagon
    • Nervous: controls hunger and appetite, coordinates muscle movement in the digestive tract
    • Excretory: removes waste materials via kidneys, lungs, liver, skin

    Body Fluids

    • Body fluids supply energy, oxygen, nutrients, and water
    • Body fluids deliver fresh supplies and remove wastes
    • Blood travels in arteries, veins, capillaries, and heart chambers
    • Lymph travels in its own vessels, eventually draining back into the bloodstream

    The Digestive System

    • Digest: Breaks down food molecules into smaller components
    • Absorb: Extracts nutrients and delivers them to the body
    • Excrete: Removes waste material after digestion is complete
    • The digestive tract is 8 meters long, flexible, and muscular
    • The digestive tract has accessory organs (salivary glands, liver, gallbladder, pancreas) aiding digestion

    Digestion

    • Mechanical digestion: begins in the mouth (chewing), involves peristalsis (wave-like muscle movements) in the esophagus, stomach, and intestines, and sphincters regulating food flow
    • Chemical digestion: enzymes break down carbohydrates, proteins, and lipids
    • Chyme: fluid resulting from stomach's action
    • Feces: waste material remaining after digestion and absorption

    Transit Time

    • Approximately 24 hours for food to travel through the digestive system
    • Transit time varies depending on the type and amount of food consumed

    Small Intestine

    • Beginning section called duodenum
    • Comprised of villi and microvilli
    • Site for nutrient absorption
    • Contains microbiota
    • Some digestive enzymes on surface for last-minute nutrient breakdown

    Large Intestine, Appendix, and Diverticula

    • Diverticula are abnormal pockets in colon wall, potentially entrapping feces, causing infection, and requiring medical intervention.
    • Appendix is a small sac protruding from large intestine, hosting beneficial microorganisms.

    The Microbiota

    • Diverse community of 100 trillion microbes in the digestive tract (mostly in large intestine)
    • Includes beneficial bacteria, yeast, and other microorganisms
    • Supports digestion by fermenting fibers into short-chain fatty acids (SCFAs)
    • Produces essential vitamins like K2
    • Strengthens immunity
    • Influences hormone production

    Absorption

    • Stomach: absorbs alcohol (20% of total) and a minor amount of water
    • Small intestine: absorbs calcium, magnesium, iron, other minerals, glucose, amino acids, fats, vitamins, water (70-90% of total), alcohol (80% of total), and bile acids
    • Large intestine: absorbs sodium, potassium, some fatty acids, vitamin K and biotin, gases, water (10-30% of total)

    Storage

    • Body designed to eat at intervals
    • Cells need a constant nutrient supply
    • Major storage sites include liver (carbohydrates), muscles (carbohydrates), and fat cells (fats and related substances)

    Undernutrition

    • Digestive system sensitive to malnutrition
    • Severe undernutrition shrinks absorptive surface of small intestine, causing impaired digestion, worsening malnutrition
    • Undernutrition can lead to downregulation of specific enzymes, but these mechanisms can recover given adequate nutrition

    Studying That Suits You

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

    Quiz Team

    Related Documents

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser