Body Plan Lecture Notes

Kingdom: Animal → A living organism capable of independent movement

Cell membrane, organelles, energy from organic/O2

Subphylum: Vertebrate → Four limbs with five digits for terrestrial transition (Pentadactyl limbs) → Protection, support, locomotion

Warm Blooded: Due to presence of metabolic rate

Four Chambered Heart: Allows pulmonary and systemic vascular systems to be arranged in parallel.

Binocular Vision: Determine distance (jumping), predators → Stereoscopic

• Info is taken from both eyes to the visual cortex for brain interpretation.

ORGAN SYSTEMS

• Somatic: Skeletal, articular, muscular, integumental
• Visceral: Respiratory, digestive, urogenital, endocrine
• Supply: Nervous, arterial, venous, lymphatic

Reproductive Success & Skin: Highly melanised skin protected against UV-induced photolysis of FOLATE which is essential for normal development of the embryonic neural tube.

Speech: Lengthened Pharynx

• Can breathe and swallow simultaneously as air and food pathways don’t cross.
• Development: pharynx lengths as larynx descends into the neck.
• Swallow & Cough reflexes, gag & vomit reflexes to protect the airway.

[pic 1]

[pic 2]

• Segmented body wall = greater movement
• Development from Germ Layers
• Segmentation is important for diagnosing disease. There is a clear pattern in trunk.
• HEAD: Brachial arches, Brainstem, cranial nerves
• Spinal Nerve: 12 cranial nerve in Cranial to Caudal sequence.

• Paraxial Mesoderm: Somites arrange in pairs along the trunk
• Sclerotome (vertebral skeleton) & derma-myotome (skin/skeletal muscle)

“Head & Tail” → Gill Slits are transient at the Head.

[pic 3]

Cranial: HEAD, Caudal: TAIL

Head end = buccopharyngeal membrane (Endoderm)

Tail =Cloacal membrane (Ectoderm)

Dermatome & Myotome arrangement

Basic Tissues: Epithelia, Connective, Muscle, Nervous

[pic 4]

Notochord = flexible rod of support (Phylum: Chordate)

Neural tube = dorsal hollow nerve cord

Skin appendages: hair, sweat glands

Mammary Glands: Breast Feeding

Opposable Thumbs, Binocular Vision, Large Brain, Hand/eye coordination.

Upright Stance, Skull, S-shaped spine, Arched foot

Body Cavities:

• Ventral Cavity: Thoracic cavity above & Abomino-pelvic cavity below the diaphragm.
• Dorsal Cavity: Cranial and vertebral cavities.

Bilateral symmetry: facilitates movement via skeleton and associated muscles

Asymmetrical regions & structures

• Exception to bilateral symmetry = serous sacs within thoracic/abdomini-pelvic cavities, with the unpaired organs (heart, digestive, spleen) and unpaired vessels.
• Left and Right lungs are slightly different sizes and shaped differently.

Flexor/Extensor Regions

• Flexor muscles (richer nerve supply) are ventral
• Extensor muscles (covered by hairier skin/tough dermis) are dorsal.

MESODERM: connective tissues & vessels.