Chapter-1 Pg:- 14,15,16. (*The majority of the content was from the Internet not from textbooks*)
Frogs are amphibians known for their unique anatomical adaptations that allow them to live both in water and on land.
External Anatomy:
Skin:
Moist and Permeable: Frog skin is smooth, moist, and permeable, allowing for cutaneous respiration (gas exchange through the skin).
Camouflage: The skin often has coloration and patterns that help frogs blend into their environment, protecting them from predators.
Glands: Frogs have mucous glands that keep the skin moist and poison glands that secrete toxins as a defense mechanism.
Head:
Eyes: Large, bulging eyes with a nictitating membrane (a transparent third eyelid) that protects the eyes underwater and keeps them moist on land.
Ears: Tympanic membranes (eardrums) located just behind the eyes, used for hearing both in water and on land.
Nostrils: Located on the top of the snout, allowing frogs to breathe while mostly submerged.
Mouth:
Tongue: Long and sticky, attached at the front of the mouth, used to catch prey.
Teeth: Maxillary teeth on the upper jaw and vomerine teeth on the roof of the mouth, used to grip prey rather than chew.
Limbs:
Front Legs: Short with four toes, used for support and to absorb shock when landing after a jump.
Hind Legs: Long and muscular with five toes and webbing, adapted for jumping and swimming.
Internal Anatomy:
Skeletal System:
Vertebral Column: Provides structural support and flexibility.
Skull: Lightweight and fused to protect the brain and support sensory organs.
Limbs: Bones in the hind limbs are elongated and adapted for jumping, with a strong pelvic girdle for muscle attachment.
Muscular System:
Leg Muscles: Strong and powerful, especially in the hind legs, for jumping and swimming.
Jaw Muscles: Adapted for catching and swallowing prey.
Digestive System:
Mouth: Contains the tongue, teeth, and salivary glands.
Esophagus: A tube that carries food from the mouth to the stomach.
Stomach: Stores and begins digestion of food.
Intestines: Further digest and absorb nutrients; the small intestine is where most digestion occurs, and the large intestine absorbs water.
Cloaca: A common cavity for the release of digestive wastes, urine, and reproductive cells.
Respiratory System:
Lungs: Frogs have simple lungs for breathing air.
Skin: Frogs can also absorb oxygen directly through their skin, especially when underwater.
Buccal Cavity: Frogs use buccal pumping to move air into their lungs.
Circulatory System:
Heart: Three-chambered heart (two atria and one ventricle) that pumps blood throughout the body.
Blood Vessels: Arteries, veins, and capillaries that transport blood.
Excretory System:
Kidneys: Filter waste from the blood and excrete it as urine.
Bladder: Stores urine before it is expelled through the cloaca.
Reproductive System:
Male Frogs: Have testes that produce sperm, which is released through the cloaca.
Female Frogs: Have ovaries that produce eggs, which are also released through the cloaca.
Fertilization: Usually external, with males releasing sperm over the eggs as females lay them in water.
Nervous System:
Brain: Controls the frog's activities, including movement, behavior, and sensory processing.
Spinal Cord: Transmits signals between the brain and the rest of the body.
Nerves: Carry signals to and from the brain and spinal cord to muscles and sensory organs.
Sensory Organs:
Eyes: Adapted for vision both in water and on land, with a keen ability to detect movement.
Ears: Tympanic membranes for detecting sound.
Skin Receptors: Sensitive to touch, temperature, and chemicals in the environment.