Lecture 6 Movement in Animals

• • a key characteristic in animals
  • an act of changing location or position
  • can be at the molecular, cellular, tissue or organismic level

  Movement
• What are the types of movements in animals?

  non-muscular and muscular movements
• What are the three non-muscular movements?

  amoeboid, ciliary, flagellar
• What are the types of muscles?

  skeletal, smooth, cardiac
• Amoeboid Movement in Protozoans

  • found in some types of protozoans (not animals)
  • uses pseudopodia or false feet
  • cytoplasmic projections formed from the streaming of cytoplasm
  • Purposes:
  • capture food
  • glide across surface
  • escape danger
• Amoeboid Movement in Protozoans

  • Portion of its ectoplasm is transformed into a gel and its endoplasm flows into this direction
  • Then, the cell membrane expands forming a pseudopodium that pushes forward
  • When the endoplasm reaches the tip of the pseudopodium it is converted into a sol (ectoplasm)

  
• Amoeboid Movement in Protozoans

  <i> Naegleria fowleri <i>

  • amoeboid protozoan
  • also known as “brain-eating” amoeba
  • can reach the brain through amoeboid movement when contaminated water enters the nasal cavity

  
• Leukocytes or white blood cells

  A) floating

  B) capture rolling

  C) adhesion

  D) crawling

  E) diapedesis

  
• Leukocytes like neutrophil, eosinophil and monocyte respond to chemicals released from site of infection or tissue injury


  This response is known as chemotaxis
• Diapedesis is the movement into and out of blood vessel wall

  Leukocyte moves by amoeboid motion
• • a monocyte transforms into a macrophage outside blood vessels

  • a macrophage can “move” about tissue spaces

  • when macrophage encounters a pathogen like bacteria, it extends portions of its cytoplasm around the bacterium to enclose it in a vacuole called phagosome for digestion

  • this process is called phagocytosis
• Ciliary Movement: Structure of Cilium (plural: cilia)

  • 1-10 μm long and less than 1 μm wide
  • hair-like structure
  • each cilium has a microtubule backbone characterized by ‘9+2’ architecture
  • has nine outer doublet microtubules
  • has a pair of central microtubules
  • Function: used to move an entire cell or substance along the outer surface of a cell
• Ciliary Movement in Protozoans

  • involves the use of cilia (singular: cilium) for movement in a fluid medium

  
• Ciliary Movement in Invertebrates

  • Gill filaments of molluscs have cilia
  • These cilia beat to drive water through the mantle cavity or to clean the gills

  
• Ciliary Movement in Invertebrates

  • cilia at the inner surface of the tube feet of echinoderms help circulate water

  
• CIliary Movement in Vertebrates

  A) mucociliary clearance

  
• What destroys cilia?

  A) smoking

  B) vaping

  C) air

  
• Ciliary Movement in Vertebrates

  • Lining of the inner wall of the female fallopian tube is ciliated
  • These cilia move the egg cell or ovum along its length

  
• Flagellar Movement: Structure of Flagellum

  A) whip-like

  B) central

  C) protein

  
• Structure of Flagellum

  A) dynein

  
• Free-Living Flagellated Protozoan

  A) Euglena

  
• Flagellated Pathogenic Protozoans

  A) motility

  
• Flagellar Movement in Animals

  A) flagellum

  
• Muscular Movement

  • Movement in animals is possible because of striated muscles or smooth muscles
  • Invertebrates have smooth muscles
  • Vertebrates possess both striated and smooth muscles
• Types of Muscles in Vertebrates

  A) yes

  B) tongue

  C) somatic nervous system

  D) yes

  E) no

  F) sinoatrial

  G) cardiac

  H) autonomic

  I) myocardium

  J) no

  K) no

  L) ANS

  M) blood vessels

  
• Structural Organization of a Skeletal Muscle

  A) bone

  B) tendon

  C) epimysium

  D) perimysium

  E) endomysium

  
• Structural Organization of a Skeletal Muscle Fiber

  A) actin

  B) myosin

  C) striation

  D) myofibrils

  E) myofilaments

  
• Structural Organization of a Skeletal Muscle Fiber

  A) Anisotropic

  B) Isotropic

  
• Structural Organization of a Skeletal Muscle Fiber

  A) Sarcomere

  B) Myosin

  
• Structural Organization of a Skeletal Muscle Fiber

  A) Actin

  B) H zone

  
• Structural Organization of Myofilaments

  A) H Zone

  B) A Band

  
• Troponin and Tropomyosin

  A) Regulatory proteins

  B) Tropomyosin

  C) Troponin

  
• Formed by the nerve fiber and the muscle it innervates

  A) Neuromuscular Junction

  
• Sliding Filament Theory of Muscle Contraction

  Resting Membrane Potential

  • Result of difference in the concentration of ions inside and outside the cell
  • Difference in the number of potassium ions (K+) across the cell membrane dominates the resting membrane potential
  • All voltage-gated sodium ion (Na+) channels and some voltage-gated potassium ion (K+) channels are closed
  • The Na+/K+ transporter pumps K+ into the cell and Na+ out of the cell
• Action Potential

  A) depolarization

  B) repolarization

  
• Action Potential: Depolarization

  • Some sodium channels open causing Na+ ions to enter the cell
  • Cytoplasm becomes less negative
  • Results to depolarization where electrical charge across the membrane is reduced (lessens)
  • All Na+ channels open when the threshold of excitation is reached
• Action Potential: Repolarization

  • Voltage-gated Na+ channels slowly close while voltage-gated K+ channels open
  • Results to movement of K+ from the cytoplasm to the extracellular medium
  • Potential across the plasma membrane becomes less negative resulting to repolarization
• Action Potential: Hyperpolarization

  • Results from K+ continually leaving the cell
  • Na+ channels are still closed
  • K+ continue to leave the cell
  • Membrane potential becomes more negative than its resting potential
  • Cell membrane in a refractory state and cannot fire
  • Stops when K+ channels close
• Muscle Fiber Activation

  A) Impulse

  B) synaptic vesicles

  C) ACh

  D) synaptic cleft

  E) receptors

  
• Muscle Fiber Activation

  A) T tubules

  B) calcium

  C) sarcoplasmic reticulum