Ecology is the scientific study of the relationships that living organisms have with each other and with their natural environment. Ecosystems are composed of dynamically interacting parts including organisms, the communities they make up, and the non-living components of their environment. Ecosystem processes, such as primary production, pedogenesis, nutrient cycling, and various niche construction activities, regulate the flux of energy and matter through an environment.

Correct Option: C

Ecology is the scientific study of the relationships that living organisms have with each other and with their natural environment. Ecosystems are composed of dynamically interacting parts including organisms, the communities they make up, and the non-living components of their environment. Ecosystem processes, such as primary production, pedogenesis, nutrient cycling, and various niche construction activities, regulate the flux of energy and matter through an environment.

An exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton (endoskeleton) of, for example, a human. Chondrichthyes or cartilaginous fishes are jawed fish with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone.

Correct Option: D

An exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton (endoskeleton) of, for example, a human. Chondrichthyes or cartilaginous fishes are jawed fish with paired fins, paired nares, scales, a heart with its chambers in series, and skeletons made of cartilage rather than bone.

Archaeopteryx, sometimes referred to by its German name Urvogel, is a genus of early bird that is transitional between feathered dinosaurs and modern birds. It shares the following features with the deinonychosaurs:: jaws with sharp teeth, three fingers with claws, a long bony tail, hyperextensible second toes ("killing claw"), feathers (which also suggest homeothermy), and various skeletal features.

Correct Option: B

Archaeopteryx, sometimes referred to by its German name Urvogel, is a genus of early bird that is transitional between feathered dinosaurs and modern birds. It shares the following features with the deinonychosaurs:: jaws with sharp teeth, three fingers with claws, a long bony tail, hyperextensible second toes ("killing claw"), feathers (which also suggest homeothermy), and various skeletal features.

Infants under four months of age that drink water or eat food contaminated with high levels of nitrates or nitrites are particularly at risk for methemoglobinemia, or blue baby syndrome. This can occur if water containing high levels of nitrates is used to prepare infant formula, and very rarely if infants eat nitrate-rich spinach which has broken down into nitrite during storage.

Correct Option: C

Infants under four months of age that drink water or eat food contaminated with high levels of nitrates or nitrites are particularly at risk for methemoglobinemia, or blue baby syndrome. This can occur if water containing high levels of nitrates is used to prepare infant formula, and very rarely if infants eat nitrate-rich spinach which has broken down into nitrite during storage.

The kidneys are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and regulation of blood pressure (via maintaining salt and water balance). They serve the body as a natural filter of the blood, and remove wastes which are diverted to the urinary bladder.

Correct Option: A

The kidneys are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and regulation of blood pressure (via maintaining salt and water balance). They serve the body as a natural filter of the blood, and remove wastes which are diverted to the urinary bladder.