Animal Classification, Nutrition, Respiration, and Reproduction

Linnean Binomial Nomenclature

Linne-binomial nomenclature (genus-species) in the animal kingdom: chordate phylum, class, mammals, primate order, family Hominidae, genus Homo, Homo sapiens species.

Arthropods

3 main groups of animals: arthropods: exoskeleton made of chitin, articulated appendages. Insects are an example.

Mollusks

Mollusks: shell, visceral mass, and mantle body (head and foot), e.g., snails.

Chordates

Chordates: Notochord and cephalization. Includes vertebrates: fish and tetrapods (amphibians, birds, mammals).

Animal Nutrition Strategies

• Filter feeders: Consume organic particles or organisms in suspension (e.g., zebra mussels).
• Substrate feeders: Live permanently in their food source (e.g., earthworms).
• Fluid feeders: Feed exclusively on fluids (e.g., Aedes albopictus mosquitoes).
• Predators: Eat relatively large prey or parts thereof (e.g., crabs with claws).
• Symbiotic relationships: Obtain food through association with another species (e.g., coral polyps).

Nutrition Process

Nutrition: Ingestion, digestion (intracellular, partially intracellular, extracellular, or symbiotic), absorption, and elimination.

Respiratory Surfaces and Breathing

Respiratory surface: The part of the animal where gas exchange occurs through diffusion.

Breathing Methods

• Skin: Through the skin (e.g., worms and amphibians).
• Simple diffusion: In simple animals.
• Branchial respiration: Aquatic invertebrates (e.g., crayfish) and amphibian larvae.
• Tracheal respiration: Insects.
• Pulmonary respiration: Land snails, adult amphibians, reptiles (e.g., turtles), birds, and mammals.

Sensory and Nervous Systems

Sensory organs: (sensory cells) send information to the nervous system.

• Central nervous system: Integrates and coordinates information.
• Peripheral nervous system: Nerves that carry information.

Osmotic and Thermal Regulation

Osmotic regulation: Osmosis balances the salt concentration in the animal's body with its aquatic environment. Water intake through gills.

Thermal Regulation

• Homeotherms: (warm-blooded) use mechanisms like sweating (sweat glands in mammals).
• Poikilotherms: (cold-blooded) have body temperature influenced by the environment.

Possibility of hibernation.

Animal Migration

Migrations: Some animals migrate, including birds, mammals, and insects.

Animal Reproduction

Animal life cycle: (e.g., Muskat tiger): Adults (sexually mature) → egg → larva (several stages) → nymph or pupa → adult.

Types of Reproduction

• Protozoa:
  • Ciliates: Asexual reproduction by binary fission and sexual reproduction by conjugation.
  • Plasmodium (malaria parasite): Asexual reproduction by sporulation.
• Asexual reproduction: (one parent, mitosis generates genetically identical offspring).
  • Budding: In sessile or slow-moving species (e.g., sponges and polyps).
  • Fragmentation: In echinoderms, flatworms, and worms.
• Sexual reproduction: Male and female → meiosis → gametes (sperm and egg) → fertilization → zygote → mitosis → embryo → new animal similar to parents.
• Parthenogenesis: Development of a new individual from an unfertilized egg (in insects and crustaceans).
• Hermaphroditism: An individual produces both eggs and sperm. Cross-fertilization (e.g., earthworms).
• Sexual dimorphism: Males and females of a species have different morphological characteristics.