answers to 3220 lab objectives

Answers, BIO 3220, Laboratory Objectives


1. Notochord, Pharyngeal slits, endostyle or thyroid tissue, dorsal hollow nerve cord, postanal tail.

2. See pp. 3-4.


1. Phylum Chordata, Subphylum Cephalochordata – as in the lancelets.

2. It is the closest non-vertebrate relative. It has many similar characteristics to vertebrates.

3. Myomere is an adult muscle segment. Myotome is a more embryonic term.

4. Larva swim and adults are sedentary filter feeders.


1. Phylum Chordata, Subphylum Vertebrata

2. A living Agnathan which includes lampreys and hagfish. Both jawless, no bone, single median nostril.

3. Ammocoetes

4. Adult is parasitic and drinks blood or body fluids from host. The adult spawns and dies, Ammocoetes larva develops in fresh water and lies in sediment with its mouth protruding from the ground and transforms up to 7 years later into a parasitic adult.

5. Jawless, without jaw.

6. Myomere – muscle segment in adult form

Myotome – muscle segment in an immature form.

CHAPTER 5 & 23

1. Fish scales are dermal.

2. Epidermis, dermis

3. Protein in epidermis to decrease water loss, protect against mechanical damage…

4. Claw, hoof, hair, nail, horn, gland, antlers…


1. Support, allows movement, muscle attachment, protection, mineral storage, blood formation.

2. Axial – skull, vertebrae, sternum, ribs

Appendicular – Girdles & appendages

3. Bones supporting the pectoral & pelvic appendages (limbs or fins).

4. Endochondral bone is cartilage model that is replaced by bone. Dermal bone comes from mesenchyme and is dermal in origin without cartilage precursor.

5. Dermatocranium – Dermal

Chondrocranium/Neurocranium and Splanchnocranium – Endochondral

6. Slit-like opening, hole/holes in bone for blood vessels or nerves to pass through.

7. Polyphyodont is continuous tooth replacement, diphyodont is two sets of teeth.

8. 3: 1: 3: 1: x 2 = 30

3: 1: 2: 1

9. A primary palate is the roof of the oropharyngeal cavity. A secondary palate separates the oral and nasal cavity by the hard/soft palate.

10. Turbinates = conchae are scroll-like surfaces in the nasal cavity that increase the surface available for air in order to warm and moisturize air and provide olfaction.

11. Immovable skull joint.

12. Caudal vertebrae have hemal arches/spines.

13. Notochord becomes reduced; regional differentiation

14. Head and neck movement.

15. Pelvic girdle support.

16. 2 points of attachment to vertebrae; capitulum with centrum and tuberculum with transverse process

17. Urostyle – fused postsacral vertebrae in the Frog (Anuran)

Pygostyle – last few fused caudal vertebrae in Aves

18. Separate cervical vertebrae allows mobility; synsacrum is fused fro rigidity for firm axis for flight.

19. Synsacrum – last few thoracic, all lumbar, all sacral, first few caudal vertebrae in birds.

20. Girdles – Appendicular skeleton that supports limbs or fins. Pterygiophores are skeletal rods in support of fins.

21. Claspers on males for copulation.

22. Phalanx

23. 3 fused pelvic girdle bones; ilium – dorsal; ischium – ventral & caudal; pubis – ventral & cranial

24. Pectoral girdle has dermal elements decreasing

Evolution of jaws for more active feeding & lifestyle

Gill bars evolve into jaws

Middle ear bones evolve

Structural changes result from changes in species environment and lifestyle.

CHAPTER 7, 16, 25

1. Cardiac muscle is in the heart and is striated and involuntary.

Smooth muscle is in the wall of tubular structures such as intestine, and is not striated and is involuntary.

Skeletal muscle is attached to the skeleton and is striated and voluntary.

2. Belly is fleshy middle of muscle, origin is the point of attachment to the skeleton at the less-moveable end (usually proximal) and insertion is the point of attachment to the skeleton and the more-moveable end (usually distal).

3. Abduct – away from body

Adduct – towards body

Depress – lower

Extend – increase angle between bones

Flex – decrease angle between bones

Levate – raise

Protract – move forwards

Retract – move backwards

Rotate – Turn around center axis

4. Prime mover, or agonist, is the main muscle whose contraction causes the desired movement. Syngergist helps the prime mover, fixator is a stabilizing muscle, like the Rotator cuff muscles stabilizing the scapula, and an antagonist opposes the desired movement.

5. “branch” = gill; “hypo” = below – as in hypobranchial muscles from pectoral girdle to mandible

6. “coraco” = coracoid

“cleido” = clavicle

“genio” = chin

7. Quadriceps femoris group includes Vastus lateralis, Vastus intermedius, Vastus medialis, Rectus femoris

Hamstrings include: Biceps femoris, Semitendinosus, Semimembranosus

Triceps surae are the two heads of Gastrocnemius and the soleus.

CHAPTER 8, 17, 26

1. Sheets that are folds of peritoneum; function to suspend viscera and support blood vessels and nerves.

2. Pertaining to internal organs

CHAPTER 9, 18, 27

1. Ingestion, physical & chemical breakdown, absorption, elimination of waste

2. Teeth, gizzard

3. Respiratory and digestive passageway, includes gills.

4. Increase surface area or slow food down for more time in the digestive tract.

5. Villi, spiral valves, ceca

6. Liver is the primary hub for all metabolism. It stores energy, detoxifies, and synthesizes bile.

7. Buoyancy

8. It contains no muscle, it is just an elevation of the floor of the oral cavity.

9. Circular muscle

10. Gas exchange between environment and bloodstream.

11. It is a modified gill slit that serves for water intake.

12. Yes, amphibians can have gills and exchange gasses through skin.

13. Duodenum, Jejunum, Ileum

14. Parotid, Mandibular, Sublingual

15. Salt excretion.

CHAPTER 11, 29

1. Blood, blood vessels, heart

2. Veins carry blood towards the heart & arteries carry blood away from the heart.

3. Exchange – diffusion

4. Veins

5. Gas exchange route & systemic route are not separate. Deoxygenated blood to heart to gills to whole body and back to heart.

6. Afferent – towards

Efferent – away from

7. Portal starts and ends in a capillary bed. The Hepatic Portal system starts as capillaries in the digestive viscera and ends in capillary beds in the liver.

8. “Lien” = Spleen

“Hepat” = Liver

“Pulm” = Lungs

“Lingu” = Tongue

“Gastr” = Stomach

“Costo” = Rib

“Inter” = Between

9. Left and right atrium, left and right ventricle

10. One way blood flow

CHAPTER 10, 19, 28

1. Maintain blood homeostasis and excretion of waste.

2. Produce gametes (egg & sperm) and produce sex hormones

3. External to the parietal peritoneum.

4. Clasper

5. Deliver live young, cat

6. Lay eggs, chicken

CHAPTER 12, 30

1. Sensory, Integration, motor

Receptor – receiver that converts stimulus such as light into electrical nerve impulse

Effector – responder, such as muscle or gland

2. Central Nervous System – Brain & Spinal cord

Peripheral Nervous System – Afferent & Efferent nerves

3. Afferent – sensory

Efferent – motor

4. Somatic – Skeletal muscle, skin, bones

Visceral – liver, intestine, lung, heart, stomach

5. Mixed is sensory and motor

6. Anamniotes have 10 cranial nerves – refer to book for names

7. Amniotes have 12 cranial nerves – same 10 as above plus Accessory and Hypoglossal.

8. Optic is a sensory tract that is an extension of the brain.

9. Forebrain- Prosencephalon

Midbrain – Mesencephalon

Hindbrain – Rhombencephalon

Telencephalon, Diencephalon, Mesencephalon, Metencephalon, Myelencephalon

10. See Table 16.2 in Kent.

11. Dura mater, Arachnoid, Pia mater

12. Photoreception in lower vertebrates, endocrine (hormones) in higher vertebrates