Frog Zoology: Integrated Anatomy and Physiology

Comprehensive practice flashcards covering the integumentary, skeletal, muscular, digestive, respiratory, circulatory, nervous, and urogenital systems of frogs, as well as embryonic development and taxonomy principles.

How many million years ago did amphibians evolve?

According to the transcript, amphibians evolved approximately $280$ million years ago.

What are the four groups included in the class Amphibia?

Amphibians include frogs, toads, salamanders, and caecilians (snakelike animals).

What does the name 'Amphibian' literally mean?

It means "two lives".

Compare the body shape and skin of a Frog versus a Toad.

Frogs have a slender body with smooth and moist skin, while toads have a more bulky body with dry skin covered with wart-like glands.

What type of teeth are found in frogs but absent in toads?

Maxillary and Vomerine teeth.

Define the anatomical position term 'Dorsal'.

Dorsal refers to the back region.

Define the anatomical position term 'Ventral'.

Ventral refers to the belly region.

What are nuptial pads and which gender possesses them?

Nuptial pads (or larger thumb pads) are found in males and are used for gripping females during mating.

Name four biological functions of a frog's moist skin in the integumentary system.

Absorbing oxygen and releasing carbon dioxide, regulating salt content and absorbing water, changing color for camouflage, and secreting mucus to prevent drying out.

What bones constitute the Axial skeleton of a frog?

The Axial skeleton contains the skull, upper and lower jaw, hyoid apparatus, sternum, and vertebral column.

What bones constitute the Appendicular skeleton of a frog?

It includes the pectoral (shoulder) girdle, forelimb skeleton, pelvic (hip) girdle, and hindlimb skeleton.

What is the function of the Premaxillae bones in the skull?

The premaxillae are small bones at the front of the upper jaw that hold teeth to help with gripping prey.

What is the Foramen Magnum?

The large opening at the base of the skull through which the spinal cord passes, connecting the brain to the spinal cord.

Which bone forms the floor of the braincase in the ventral view of the skull?

The Parasphenoid bone.

What are the two primary bones that compose the frog's mandible (lower jaw)?

The dentary and the angular (angulosplenial) bones.

What is the role of the Hyoid Apparatus in frogs?

It provides attachment for muscles controlling the tongue's rapid movement and supports the larynx, facilitating respiration and vocalization.

What is the role of the Urostyle in frog locomotion?

The Urostyle helps transfer the force of a jump to the pelvic girdle.

What are the two major components of a frog's forearm skeleton?

The Radius and the Ulna.

Define the musical system terms 'Origin' and 'Insertion'.

Origin is the fixed and less movable point of attachment, while Insertion is the point of attachment that allows movement.

Explain the difference between Flexors and Extensors.

Flexors bend a part, while Extensors straighten a part.

Explain the difference between Abductors and Adductors.

Abductors draw a part away from the middle, while Adductors draw a part toward the middle.

Why is a frog's tongue described as 'prehensile'?

Because it is sticky and can be extended quickly to capture and pull insects back into the mouth.

Describe the characteristics of frog teeth using the terms Homodont, Acrodont, and Polyphyodont.

Frogs are Homodont (all teeth similar shape), Acrodont (attached to bones, not in sockets), and Polyphyodont (continuously replaced throughout life).

What are the three modes of respiration in adult frogs?

Cutaneous (skin), Buccopharyngeal (mouth lining), and Pulmonary (lungs).

Which respiration method is the sole organ of gas exchange during hibernation and aestivation?

Cutaneous Respiration (through the skin).

Name the two types of cartilage that support the frog's larynx.

The arytenoid cartilage and cricoid cartilage.

Describe the layers of the frog's heart sac.

The heart is enclosed in a double membrane sac consisting of the outer Pericardium and the inner Epicardium, with serous (pericardial) fluid in between.

What are the three chambers of the frog heart?

Two atria (auricles) and one ventricle.

What is the function of the Carotid Labyrinth (Carotid Body)?

It detects pressure changes in oxygen levels in the blood.

List the three concentric layers of an artery.

Tunica Intima (innermost), Tunica Media (middle), and Tunica Externa or Adventitia (outermost).

Which aortic arch divides into the pulmonary and cutaneous arteries?

The Pulmocutaneous Arch.

What percentage of frog blood is plasma vs. corpuscles?

Plasma makes up about $60\%$ and blood corpuscles make up $40\%$.

What are the measurements and average lifespan of a frog erythrocyte?

The size is $23 \times 14\,\mu m$ and the lifespan is approximately $100$ days.

Which substance in the blood prevents clotting during normal circulation?

Antithrombin (heparin).

Identify the two types of frog kidneys based on life stage.

In tadpoles, they are Pronephros; in adults, they are Mesonephros.

What is a Malpighian body?

The combination of the Bowman’s capsule and the glomerulus within the kidney.

Identify the location and function of Interstitial cells in the testes.

They are located between seminiferous tubules and secrete testosterone to develop secondary sexual characteristics.

Differentiate between the Animal hemisphere and the Vegetal hemisphere of a frog egg.

The Animal hemisphere is the dark, pigmented upper half containing the nucleus, while the Vegetal hemisphere is the light lower half containing the white yolk.

What are the divisions of the frog brain?

Forebrain (Prosencephalon), Midbrain (Mesencephalon), and Hindbrain (Rhombencephalon).

List the first ten cranial nerves by name.

I Olfactory, II Optic, III Oculomotor, IV Trochlear, V Trigeminal, VI Abducens, VII Facial, VIII Auditory, IX Glossopharyngeal, and X Vagus.

What is the 'Cauda Equina' in the frog nervous system?

A bundle of roots from the last four pairs of spinal nerves that look like a horse's tail inside the vertebral column.

What chemical is released by Parasympathetic fibers when stimulated?

Acetylcholine, which has an inhibitory effect on organs.

What is the significance of the Gray Crescent during fertilization?

It appears opposite the sperm entry point and foretells the future pattern of the animal (dorsal/ventral, anterior/posterior, left/right).

Define the term 'Blastocoel'.

A fluid-filled cavity that develops within the hollow ball of cells called the blastula.

What is Gastrulation marked by in frog development?

The invagination of cells to produce the blastopore (future anus) and the formation of three germ layers: ectoderm, mesoderm, and endoderm.

Differentiate between Homologous and Analogous structures.

Homologous structures share a common ancestor but have different functions, whereas Analogous structures have similar functions but evolved independently.