Key term : Animal physiology

Porifera

are sponges that filter-feed and do not have true tissues or organs.

Cnidaria

include jellyfish, corals, and anemones and have stinging cells called cnidocytes.

Nematoda

are unsegmented roundworms with a complete digestive tract.

Platyhelminthes

are flatworms with bilateral symmetry and usually an incomplete digestive system.

Annelida

are segmented worms such as earthworms.

Echinodermata

include sea stars and sea urchins and have a water vascular system.

Arthropoda

include insects, crabs, and shrimp and have jointed appendages and an exoskeleton.

Rotifera

are tiny aquatic animals with a ciliated corona used for feeding and swimming.

Vertebrata

s are animals with a skull and vertebral column.

Bilateral symmetry

means the body can be divided into matching left and right halves.

Radial symmetry

means the body is arranged around a central axis

Triploblastic

animals have three germ layers: ectoderm, mesoderm, and endoderm

Diploblastic

Animals have two germ layers: ectoderm and endoderm.

Ectoderm

is the outer germ layer that develops into skin and the nervous system.

Mesoderm

is the middle germ layer that develops into muscles, skeleton, blood, and many organs

Endoderm

is the inner germ layer that develops into the digestive tract and related organs.

Protostome

the first embryonic opening becomes the mouth.

Deuterostome

the first embryonic opening becomes the anus.

Synapomorphy

Synapomorphy A synapomorphy is a shared derived trait that identifies a group of organisms.

Phylogeny

shows the evolutionary history and relationships between organisms.

Metabolism

is the sum of all chemical reactions in an organism.

Metabolic rate

is the amount of energy an organism uses per unit of time.

Direct calorimetry

measures the heat produced by an organism.

Indirect calorimetry

estimates metabolism by measuring oxygen use or carbon dioxide production.

Basal metabolic rate

rate is the minimum energy use of a resting endotherm.

Standard metabolic rate

is the minimum energy use of a resting ectotherm at a specific temperature.

Field metabolic rate

is the average energy use of an animal living normally in nature.

Active metabolic rate

is the energy an animal uses during maximum sustained activity.

Whole-body metabolic rate

is the total energy use of the entire animal.

Mass-specific metabolic rate

is energy use measured per unit of body mass.

Endotherm

produces most of its body heat internally.

Ectotherm

gets most of its body heat from the environment.

Thermal neutral zone

is the temperature range where an endotherm uses minimum energy.

Regulator

keeps its internal conditions relatively stable despite environmental changes.

Conformer

internal conditions change with the environment.

Aerobic respiration

uses oxygen and produces a large amount of ATP.

Anaerobic respiration

occurs without oxygen and produces less ATP.

Glycolysis

breaks glucose into pyruvate and produces a small amount of ATP

Pyruvate

is the end product of glycolysis and can enter aerobic respiration.

Citric Acid Cycle

produces electron carriers, carbon dioxide, and a small amount of ATP.

Oxidative phosphorylation

uses energy from electrons to produce ATP

Electron Transport Chain

passes electrons and creates a proton gradient used to make ATP.

Lactic acid

can be produced during anaerobic glycolysis when oxygen is limited.

Brown adipose tissue

produces heat through non-shivering thermogenesis.

P/O ratio

compares ATP production with oxygen use.

Digestion

Digestion breaks food into smaller molecules that can be absorbed.

Absorption

moves digested nutrients from the gut into the body.

Head gut

is the most anterior part of the digestive tract and includes the mouth.

Foregut

includes the esophagus and stomach and helps with storage and digestion (Stomach)

Midgut

is mainly responsible for enzymatic digestion and nutrient absorption. ( Small intestine)

Hindgut

absorbs water and can be involved in fermentation. ( Large intestine )

Mechanical digestion

physically breaks food into smaller pieces.

Chemical digestion

uses enzymes to break food molecules into smaller molecules.

Intracellular

digestion occurs inside cells.

Extracellular digestion

occurs outside cells, usually inside a digestive tract.

Complete digestive system ( Complete gut )

has two openings: a mouth and an anus.

Incomplete digestive system

An incomplete digestive system has one opening used for both food and waste.

Amylase ( Carbs)

breaks starch into smaller sugars.

Pepsinogen

is the inactive form of pepsin.

Gastrin

increases stomach acid secretion and stomach movement.

Bicarbonate

neutralizes acidic chyme entering the small intestine.

Secretin

tells the pancreas to release bicarbonate.

Cholecystokinin

(CCK) CCK tells the gallbladder to release bile and helps with fat digestion.

Gastric Inhibitory Peptide

stimulates insulin release and slows stomach activity.

Duodenum

is the first part of the small intestine where much digestion occurs

Jejunum

is the middle part of the small intestine and absorbs many nutrients.

Ileum

is the last part of the small intestine and absorbs remaining nutrients.

Small Intestine

The section of the digestive track where most enzymatic digestion and nutrient absorption occur

Large intestines

Digestive track that absorbs water and electrolytes and houses fermentative bacteria

Cecum

is a pouch near the small and large intestine important for fermentation

Hindgut fermenter

uses microbes in the cecum or colon to digest plant material.

Foregut fermenter

uses microbes in the stomach to digest plant material.

Bile salt

Helps break up fats so they can be digested and absorbed.

Micelle

is a small structure made of bile salts and lipids that helps transport fats.

Lipase

Lipase breaks triglycerides into fatty acids and monoglycerides.

Chylomicron

Formed in intestinal cells; triglyceride repacked with a protein coat allowing it to move easily through the body.

Triglyceride

is a fat molecule made of glycerol and three fatty acids.

Triglyceride

A lipid made of glycerol bonded to three fatty acids; the main form of stored fat.