Anatomy and Physiology

Anatomy and Physiology

Form and Function

Vocab

  • Physiology
    • The study of biological systems (body-organ function)
  • Anatomy is divided into several branches
    • Gross anatomy- study of structures that can be viewed by the naked eye
    • Histology- the study of tissues with the use of a microscope
    • Comparative anatomy- compares body structure of different species
    • Embryology- the study of in-utero development

Anatomical Locations

  • Dorsal
    • Top of the animal
  • Ventral
    • Belly or underside
  • Cranial (Anterior)
    • Towards the front or head of the animal
  • Caudal (Posterior)
    • Towards the rear
  • Medial
    • To the inside; extending toward the middle
  • Lateral
    • To the outside; away from the inside
  • Anatomy
    • Focus on external parts of livestock species
  • Physiology- how systems work together
    • Integumentary
    • Skeleton
    • Muscular
    • Circulatory
    • Respiratory
    • Digestive
    • Nervous
    • Reproduction

Integumentary System

  • Exterior covering of the body
    • Skin
  • Modified appendages of skin
    • Hair
    • Woll
    • Horns
    • Feathers
    • Hooves
  • Function
    • Physical protection
    • Protection against infection
    • Temp regulation - sweat
    • Environment response – sensory nerves
    • Glands for secretion
  • Two primary layers
    • Epidermis- outer layer
    • Dermis- inner layer
  • Hair
    • Coat covering of cattle, horse, pig, goat
  • Wool
    • Coat covering of sheep- finer texture, soft
  • Feathers
    • Covering of poultry
    • Chickens molt in late summer- shed old feathers- and grow new in time for winter

Skeletal System

  • In farm animals, the skeleton is internal (endoskeleton)
    • Skeletons of farm animals are very similar
    • Qhave mostly the same bones - the size of bones may vary
  • 5 major functions
    • Support: the body is kept in position by the muscles that attach to the skeleton
    • Protection: the flat bones that protect internal organs
    • Movement: provided by the joints
    • Blood Production: blood cells are produced in the bone marrow
    • Storage: Minerals are stored in the bone, mostly calcium and phosphorus
  • Outside of the bones are hard
    • Minerals are stores- mainly calcium
  • Inside of bones are soft tissue
    • Bone marrow
      • Red marrow- blood cell formation
  • Skeleton grows as an animal grows
    • Bone growth ceases as an animal matures
    • Bone calcifies = physical maturity
  • Bone growth can be affected by
    • Nutrition- vitamins and minerals
    • Hormones
    • Exercise
  • Bones may break
    • The animal body can mend or repair a break
  • Bones are joined - at the joint
    • Held together by ligaments
    • Joins are lubricated with synovial fluid
  • Movement - made possible by joints powered by muscles
    • Ball and socket
      • Rotation all directions
        • Hips
    • Hinge joints
      • Two directions
        • Pasturn, knee, shoulder
    • Pivot joints
      • Neck- work together for directional movement
    • Gliding joints
      • Vertebrae - flex

Bone Classification

  • Long Bones- Limbs, support the weight
  • Short Bones- Knee and Hock, dissipate concussion
  • Flat Bones- ex. Ribs, Scapula, and Some bones of the skull and enclose cavities containing vital organs
  • Irregular Bones- unpaired bones, ex. Vertebrae and some skull bones

Muscular System

  • Muscle fibers made up primarily of protein
    • Actin
    • Myosin
    • Tropomyosin
    • Troponin
  • Groups-
    • Involuntary
    • Voluntary
      • Three types:
        • Skeletal
        • Cardiac
        • Smooth

Involuntary Muscles

  • It can be smooth or striated
    • Most are smooth (the 🫀heart is an exception)
  • Involuntary smooth muscles
    • Found in the walls of many body organs
      • Digestive
        • Move ingesta (🥨🥖🥩food) along the tract
      • Reproductive 🍑🍆
        • Parturition, ova (🥚egg), movement
      • Respiratory🫁
    • These muscles are controlled by the autonomic nervous system - hormones - contract or relax 🧘🏼‍♀️
  • Autonomic nervous system muscular control
    • Sympathetic is when an animal needs to get the hell out of town- speeds up muscles, heart rate, and eyes, and slows down digestion
      • Fight or flight
    • Parasympathetic slows muscles but speeds up digestion
      • Rest and digest- After a big Thanksgiving meal you need a nap

Voluntary Muscles

  • Striated muscles
  • Function when the animal calls on them
  • Skeletal muscles
    • Movement
  • The heart is a working muscle that is involuntary

Muscular Contraction

    • The actual contraction
    • Muscles made up of fibers and bundles of these fibers
      • Contraction shortens these fibers and bundles
        • Sliding or ratcheting along each other
      • Relaxation allows them to lengthen back out
  • Muscle contraction is a very complex biochemical process that uses energy
  • ATP (ADENOSINE TRIPHOSPHATE)
    • The main source of energy
    • When muscle is stimulated - ATP is broken down to form energy
  • ATP is formed by:
    • Using blood glucose to make ATP
    • Breaking down glycogen (fat) to glucose to make ATP
      • Dieting
    • Breaking down fat and protein molecules (muscles💪🏻) to make ATP
      • Starving- Last Options
      • Good dairy cattle- can’t consume enough energy because lactation takes so much energy
  • Muscle contraction can happen with or without oxygen
    • With oxygen = much more efficient and by-products are being eliminated
      • Aerobic process
    • Without oxygen = a build-up of lactic acid (can be only for a short time)
      • Anaerobic process
  • Fatigue = can’t make this reaction happen fast enough
    • Might be low on glycogen
    • Most likely low on oxygen
      • Go to no oxygen path
      • This cannot be sustained for a long period of time

Circulatory system

  • Composed of:
    • Cardiovascular system- blood distribution
    • Lymph system- Lymph distribution
  • Made up of:
    • Heart
    • Arteries
    • Capillaries
    • Veins
    • Lymph vessels
    • Lymph Nodes
  • Functions
    • Gas transport
      • Oxygen to the tissues/muscles
      • CO2 (waste gas) out via lungs - respired
    • Nutrient transport to cells
      • Glucose- for ATP production
      • Vitamins and Minerals for cell function
    • Waste transport out of the cells-body
      • Ammonia from protein digestion
        • Transported to the liver and converted to euro
        • Urea transported to the kidney
        • Excretion in urine
      • Acids from anaerobic contractions
    • Transportation hormones
      • Regulate daily functions
    • Contain cells that fight infection
    • Stabilize the pH of body fluids
    • It helps regulate body temp
  • Key contributors to the circulatory system:
    • Bone marrow
      • Production of blood cells
    • Spleen
      • Storage of blood cells
      • Removes damaged/old blood cells
  • Blood Flow
    • Heart>
    • Lungs>
    • Heart>
    • Arteries>
    • Arterioles>
    • Capillaries>
    • Venules>
    • Veins>
    • Heart

Vessels

  • Heart
    • Located in the chest (thoracic) cavity, between lung lobes
    • Pump that circulates blood throughout the body
      • Actually a double-pump
        • The right atrium and right ventricle
        • The left atrium and left ventricle
      • Valves in the heart prevent backflow
    • Failure=Death
  • Arteries
    • Blood vessels that carry oxygenated blood from the heart tissues and organs
    • One exception- is the pulmonary artery because it has not been to the lungs yet
    • Thick-walled to take pressure, and pump blood everywhere
  • Arteries branch into Arterioles
  • Capillaries
    • Smallest diameter blood vessels
      • Red blood cells travel single-file
    • Run through muscle, fat, and organ tissues
    • This is where:
      • Nutrients given to tissue cells
      • Oxygen given to tissue cells
      • CO2 waste taken from tissue cells
    • **SITE OF EXCHANGE**
  • Veins
    • Blood vessels that return blood back from tissues to the lungs and to the heart
      • Blood in veins going to the heart is low oxygen- high CO2
      • Gets oxygenated in the lungs
      • One exception to low oxygen blood in veins in the Pulmonary Vein
    • Veins are larger in diameter than arteries to make it as easy as possible for blood to return to the heart
    • Blood pressure in veins is low
      • Veins have valves to prevent backflow

Blood

  • Two parts:
    • Liquid = Plasma
    • Cells
  • Plasma
    • Water 90%
    • Dissolved gases
    • Enzymes
    • Glucose
    • Wastes
    • Salts
    • Proteins
    • Hormones
    • Antibodies
  • Erythrocytes
    • Aka- red blood cells
    • Produced in bone marrow
    • Life span in people is about 90-120 days(3-4months)
    • Filled with hemoglobin
      • This is needed for oxygen transport
      • Oxygen attaches to hemoglobin
    • Dead red blood cells are removed by the spleen
  • Leukocytes
    • Aka- white blood cells
    • Short-lived- days to weeks
    • 1 Fight disease by attacking and engulfing bacteria (Neutrophils)
    • 2 Or fight disease by producing and releasing antibodies
      • (Lymphocytes)
      • Antibodies are specific to disease organisms
      • Become immune to a disease
  • Platelets
    • Irregularly shaped and colorless
    • Coagulate-
      • Form blood clots