ZOO202 Final Term Subjective 2022 by Sulman Ali

ZOO202 Animal Diversity Chordates · FINAL TERM PAPER PREPARATION BEST FILE BY · SULMAN ALI · BS-ZOOLOGY 4TH SEMESTER · SPRING 2022 · Reproduction in tunicates :

Tunicates are generally hermaphrodites that sexually reproduce by cross-fertilization. That means that an individual does not use its own sperm to fertilize its eggs. Instead, they obtain sperm released into the open ocean by other individuals. Fertilization is usually internal.

Nitrogenous excretion in fishes:

Fishes in water excrete ammonia as the major nitrogenous waste through gills, but gills of airbreathing fishes are modified for air-breathing or largely replaced by air-breathing organs.

spectacles definition:

Lenses set in a frame that holds them in front of the eyes, used to correct errors of refraction or to protect the eyes.

Examples of annilids:

1= Earthworm. 2=Leeches. 3= Lugworms. 4= Polychaetes.

What is preening?

Preening is a maintenance behaviour found in birds that involves the use of the beak to position feathers, interlock feather barbules that have become separated, clean plumage, and keep ectoparasites in check.

Define pheromones:

A pheromone is a chemical that an animal produces which changes the behavior of another animal of the same species. Some describe pheromones as behavior-altering agents.

define cirri:

a cirri is a long, thin structure in an animal similar to a tentacle but generally lacking the tentacle's strength, flexibility, thickness, and sensitivity.

Arrector pili muscle:

A band of smooth muscle, called the arrector pili muscle. Arrector pili muscles are under the control of the autonomic nervous system, which also controls a mammal’s “fight-or-flight” response. This is a tiny muscle that attaches to the base of a hair follicle at one end and to dermal tissue on the other end. In order to generate heat when the body is cold, the arrector pili muscles contract all at once, causing the hair to "stand up straight" on the skin.

Convergent evolution:

Convergent evolution is when different organisms independently evolve similar traits. For example, sharks and dolphins look relatively similar despite being entirely unrelated.

Define amphibians:

Amphibians are small vertebrates that need water, or a moist environment, to survive. The species in this group include frogs, toads, salamanders, and newts.

Difference between monoestrus, diestrus, and polyestrus:

Monoestrous animals are those which have only one oestrous cycle in a year and hence breed only once a year. Diestrus is a period of sexual quiescence that intervenes between two periods of estrus. polyestrus having several estrus cycles annually or during a breeding season.

Altricial and precocial:

Altricial are being hatched or born or having young that are hatched or born in a very immature and helpless condition so as to require care for some time. Precocial: (young bird or other animal) hatched or born in an advanced state and able to feed itself almost immediately.

4 unique charateristics of chordates:

At developmental stages: 1= Presence of notochord 2= Presence of nervechord 3= Presence of post-annel tail 4= Presence of phyrengial slites

Role of salivary glands in lamprey:

When lampreys attack host fishes to suck blood and flesh, their buccal glands could secrete enough proteins to suppress blood coagulation, nociception, oxidative stress, immune response, as well as other adverse effects encountered during their parasitic lives.

Give an example of urochordates?

Tunicates or sea squirts.

What is Asetivation?

Aestivation (Latin: aestas (summer); also spelled estivation in American English) is a state of animal dormancy, similar to hibernation, although taking place in the summer rather than the winter.

What is hibernacula?

Individuals that are usually solitary may migrate to a common site to spend the winter. Heat loss from these groups, called hibernacula.

What is hibernation?

Hibernation is a period of winter inactivity in which the hypothalamus of the brain slows the metabolic, heart, and respiratory rates. In preparation for hibernation,mammals usually accumulate large quantities of body fat.

What is PLUMAGE?

The covering of feathers on a bird is called the plumage.

what is annuli?

Earthworms' bodies are made up of ring-like segments called annuli. These segments are covered in setae.

What is ecdysis?

The process of shedding the old skin (in reptiles) or casting off the outer cuticle (in insects and other arthropods).

Homodont and heterodont: · Homodont · Heterodont:

In reptiles, the teeth are uniformly conical, a condition referred to as homodont In mammals, the teeth are often specialized for different functions, a condition called heterodont.

Types of flight?

1= Gliding flight: during gliding flight the wing is stationary, and a bird loses altitude. Waterfowl coming in for a landing use gliding flight 2= Flapping flight: generates the power for flight and is the most common type of flying. Many variations in wing shape and flapping patterns result in species-specific speed and maneuverability 3= Soaring flight allows some birds to remain airborne with little energy expenditure. During soaring, wings are essentially stationary, and the bird utilizes updrafts and air currents to gain altitude. Hawks, vultures, and other soaring birds are frequently observed circling along mountain valleys, soaring down-wind to pick up speed and then turning upwind to gain altitude. 4= Hovering flight. They hover in still air by fanning their wings back and forth (50 to 80 beats per second) to remain suspended in front of a flower or feeding station. Eg Hummingbirds.

Shivering and non shivering?

Shivering

Non-shivering

Shivering thermogenesis is muscular activity that generates large amounts of heat but little movement. Nonshivering thermogenesis involves heat production by general cellular metabolism and the metabolism of special fat deposits called brown fat.

Difference bw ventricles and proventriculus?

Ventricles

Proventriculus

The ventriculus, or muscular stomach (also known as the “gizzard”), contains two opposing sets of muscles used for grinding food. The proventriculus, or glandular stomach, is continuous with the esophagus at the level of the base of the heart and contains digestive (pepsinogen-secreting) and mucous glands.

Define hair?

Hair is a keratinized derivative of the epidermis of the skin and is uniquely mammalian. It is seated in an invagination of the epidermis, called a hair follicle. The hair is a slender threadlike outgrowth of the epidermis of an animal.

Example of anurans?

any of an order (Anura) of amphibians comprising the frogs, toads, and tree frogs all of which lack a tail in the adult stage and have long hind limbs often suited to leaping and swimming.

What is order of humans?

the order of humans is primates.

Binocular vision?

vision using two eyes with overlapping fields of view, allowing good perception of depth.

PINEAL body?

A pineal body on the roof of the forebrain appears to stimulate ovarian development and to regulate other functions influenced by light and dark periods.

Define Spectacle?

In snakes and some lizards, the upper and lower eyelids fuse in the embryo to form a protective window of clear skin, called the spectacle. (During ecdysis, the outer layers of the spectacle become clouded and impair the vision of snakes.

Arrector pili muscles

A band of smooth muscle, called the arrector pili muscle, runs between the hair follicle and the lower epidermis. Arrector pili muscles are under the control of the autonomic nervous system, which also controls a mammal’s “fight-or-flight” response.

Counter current

Countercurrent heat-exchange systems may help regulate heat loss from exposed areas. Arteries passing peripherally through the core of an appendage are surrounded by veins that carry blood back toward the body. When blood returns to the body through these veins, heat transfers from arterial blood to venous blood and returns to the body rather than being lost to the environment . When excess heat is produced, blood is shunted away from the countercurrent veins toward peripheral vessels, and excess heat is radiated to the environment.

Negative pressure mechanisms?

In most reptiles, a negative-pressure mechanism is responsible for lung ventilation. A posterior movement of the ribs and the body wall expands the body cavity, decreasing pressure in the lungs and drawing air into the lungs. Air is expelled by elastic recoil of the lungs and forward movements of the ribs and body wall, which compress the lungs. The ribs of turtles are a part of their shell; thus, movements of the body wall to which the ribs attach are impossible. Turtles exhale by contracting muscles that force the viscera upward, compressing the lungs. They inhale by contracting muscles that increase the volume of the visceral cavity, creating negative pressure to draw air into the lungs.

Types of mammalian teeth

1= Incisors are the most anterior teeth in the jaw. They are usually chisel-like and used for gnawing or nipping. 2= Canines are often long, stout, and conical, and are usually used for catching, killing, and tearing prey. Canines and incisors have single roots 3= Premolars are positioned next to canines, and have one or two roots and truncated surfaces for chewing. 4=Molars have broad chewing surfaces and two (upper molars) or three (lower molars) roots.