Zoology exam 1

Animal Body plans

Exoskeleton

Found in invertebrates, Made of hard chitin or calcium. Muscles attatch to points inside the exoskeleton.

-Contraction creates movement

Endoskeleton

-Bones, ligaments, tendons, cartilage, muscle

Tendons attach muscle to bone

Ligament attach bone to bone

Bioenergetics

Thermoregulation

To maintain homeostatic thermoregulation animals must be able to conserve heat when it is cold outside and dissipate heat when it is hot outside

When it is cold outside—→ Vasorestriction, Shivering, Fat layers, Fur/Feathers

When it is hot outside——→ Vasidilation, panting, sweating

Set points

Deviation from set point causes physiological changes in the body to retrun back to set point.

Ex: If temp increases too much sweat will happen.

Postitive feedback

Pushes the body further out of homeostatis by maintaining the stimulation that deviates from the set point

*Not always a bad thing ex: blood coagulation

Negative feedback

Regulation that returns the body to homeostasis by changign the direction of the simulation that deviated the setpoint,

ex: again sweating

8 major animal systems

-Musculo-skeletal system

-Digestive system

-Circulatory system

-Respiratory system

-Excretory system (metabollic waste)

-Nervous system

-Sensory system

-Reproductive system

Homeostasis

Maintaning a stable environment inside an animal’s body. Dynamic equillibrium is maintained around a setpoint

Exs: Blood glucose,hydration, temp, calcium levels

Endothermic

Animals that use metabolism to maintain their body temp.

-Require 90% more calories than ectotherm

Ex: mammals and birds

Exothermic

Animals do not use metabolism to maintain their body temp

-Require only 10% of the calories than endotherm

Ex: Amphibians, reptiles

Poikilothermic

Animals allow their body temp to fluctuate depending on the environment

Ex: Typically ectotherms, but not always

Homeothermic

Animals, whether endotherms or ectotherms, maintain a constant body temp

examples: Most animals

What is physiology?

How form and function sustain life and shape responses to envionment conditions

Musculo-Skeletal system

-Provides syooirt if animals body, organs, and allows for movement.

-Vertebrates have an endoskeleton

-Invertibrate have an exoskeleton

Digestive system

mouth ———> stomach—→ intestine

-Hydrolyzes large macromolecules (portiens, carbs, fat) into smaller units (amino acidsm glucose, fatty acids)

-Those units are then abosrbed in the blood

-Not all animals have this system

Circulatory system

Transports nutrients and grases throughout the body

-The heart it the “motor” bc it circulates blood through blood vessels

-Arteries Oxygenated AWAY from heart

-Veins Deoxygenated towards heart

Respiratory system

-Abosrbs oxygen and removes CO2

-Oxygen is abosrbed and transported to cells thorughout body

-Co2 is waste product

Excretory system (metabollic waste)

-Eliminates nitrogenous waste from body, regulates blood volume and pressure, controls electrolye levels and metabolic waste, and regulates blood ph

-Kidneys, bladder, urethra

-Work closely w circulatory system

Nervous system

-Coordinate its actions and sensory inf o by transmitting signals from dif parts of body

-Brain nerves

Sensory system

-Part of nervous system that is responsible for processing sensory info.

-Neurons and neural pathways responsible for sight, sound, smell, taste, and touch

Reproductive system

Automical organs involved in sexual reproduction.

-Fluids, hormones, and pheromones are accessories

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Ctenophora

-Known as “Comb Jellies”

-Most species are marine

-No hox genes

-Vague and uncertain

-Are the basal taxon

-Most ancient

-Are acrive hunter

Ctenophora Morphology

-Biradial symmetry

-Tripoblastic prostomes (more complex tissue types: mesoderm, endoderm, ectoderm)

-No orgin for mesoderm

-Movement is from cilia

Ctenphora systems

-Unique complete digestive cell (anal pores0

-Optain oxygen and remove CO2 thru epidermal diffusion

-Are monoecious (both male and females produce eggs and sperm)

Porifera

-No hox genes

-Have specialized cells that perform “tissue like” functions

-Sponges

Poriferan Morphology

-Asymmetrical

-Sponges have a cylindrical shape

-Don’t have tissues so are neither triploblast or diploblast

-Water flows into the spongocoel (sides) and then they are expelled through the opening at the top called the osculum

-Choanocyte cells line the spongocoel to generate direction of water flow

-Amoebocyte cells, similar to stem cells, can differentiate into other cells

Poriferan Systems

Have no digestive, respiratory, or nervous system

Instead use specialized cells like choanocytes or amoebocytes

-Mainly reproduces asexually by fragmenting ( if a piece of sponge falls off new one can emerge) but can reproduce sexually

-Can reproduce sexually bc ameobocytes become eggs and choanocytes become sperm

Cnidaria

-Jellyfish, anemones, ect

-one of most ancient

-Has hox genes

Cnidaria Morphology

-Radial symmetry

-Tissues are DIploblastic

-Have a defining characteristic known as a cnidocyte, or stinging cells.

-Can either be polyp (cant move) or medusa (move)

Cnidaria Systems.

-The gastrovascular cavity somewhat acts as a digestive system

-Have specialized cells but no true organ system

-Can reproduce asexually thru budding or reproduce sexually.

-Medusa produces eggs and sperm

Nematocyst

-Organelle in a cnidocyte that contains a barb with threat wrapped around it. The thread often contains toxins that immobilize the prey.

-can only be used once

4 Cnidarian classes

-Anthozoa All Cecil (dont move). Coral

-Scyphozoa Most jellyfish

-Cubozoa Box jelly DEADLY

-Hydrozoa Man o’ war

Complexity least to most

Cnidaria<Prorifera< Ctenophora

Phylogenetically oldest to youngest

Ctenophora > Prorifera>Cnidaria