Animal Biology Flashcards
what is an osmoconformer
an organism that keep their internal fluids isotonic to their environments. Their internal salinity is the same as the water they are in often marine creatures
Define osmoregulators
organisms that actively regulate their osmotic pressure independent of their surrounding environment often freshwater
define homeostasis
the maintenance of relatively stable physical and chemical conditions of internal body fluids
why do organisms osmoregulate
organisms are open systems that exchange matter to maintain homeostasis
what are the osmoregulatory organs
gills - ionic fluxes, passive water movement
kidney - ultrafiltration, urine production
intestine - water absorption
what is the hydromineral regulation
the active regulation of osmotic pressure of body fluids so that homeostasis is maintained by the excretory systems
what are the principal waste products of animal metabolism
water, carbon dioxide, nitrogenous wastes (ammonia, urea, uric acid)
what are the excretory organs of invertebrates
Protonephridia, metanephridia, Malpighian tubes
what are Malpighian tubes
extensions of the gut wall
They are blind ends that lie in the hemocoel that are actively transport uric acid (etc) into the tubule which then passes into the gut and water
why must terrestrial vertebrates conserve water
high metabolic rate leads to large volumes if nitrogenous waste. Kidneys and other adaption conserve water
how does the vertebrate kidney work
functions in excretion and osmoregulation. Its vital to maintaining homeostasis. Its a key organ in the urinary system
how is urine formation accomplished
filtration of plasma which reabsorbs needed materials and secretes other substances
what hormone regulates urine volume
Antidiuretic hormone (ADH)
What is a circulatory system and what is it for
It is a system of blood vessals or spaces through which the blood can flow. Includes the heart, arteries etc. Delivers oxygen to cells and removes waste
describe open circulatory systems
blood is not confined to closed vessels and blood tissue exchange happens in tissue spaces called lacunae
many are organized channels through certain organ e.g. gills
what is the pericard
the vessel from each gill to heart atria. The blood from the gills collect hear and enter through the dorsal ostia
what are the problems with the open circulatory system
difficult to accurately regulate
sluggish
describe the closed circulatory system
in organisms with higher metabolic rate and contractile vessels and accessory hearts. Its always contained with in the vessals
Describe a single loop blood circulation system
in fish its a single loop system which limits rate of oxygen delivery and has low blood pressure but allows blood to be fully oxygenated leaving the gills. The heart is a tube pump
describe amphibian and reptile hearts
three chambered. Pulmonary and systemic circulation
It allows for higher blood pressure but no complete separation of vertices
describe the circulatory system in mammals and birds
four chambered. pulmonary and systemic
Advantages include complete seperation continuous perfusion of lungs and increased efficiency
what is the endocrine system
hormone and chemical signals that regulated almost every biological process including growth and development, mental development, mood, memory, sexual maturation, immune functions
what are the classes of hormones
steroids derived from cholesterol, amine derivatives and, peptides and proteins
how does the endocrine system work
hormones travel through blood until they reach their particular receptor cell. They then turn on or off functions which triggers a reaction
what are endocrine disrupting chemicals
man made compounds which fit into hormone receptors blocking normal hormones or acting instead of the hormone. AKA drugs
what are circulating hormones
hormones translated by the blood and bind to receptors on distant cells
what are local hormones
paracrine hormones which bind to receptors on nearby cells
Autocrine hormones that bind to receptors on the same cell that secretes them
what is ecdysis
Molting - necessary for crustacean to increase in size as their exoskeleton does not grow. The physiology of molting affects reproduction, behavior and many metabolic processes
what causes ecdysis
molting animals grow in the intermolt phases until their is no space within the cuticle. This is the pre-molt phase.
how does hormones control ecdysis
ecdysis is started by CNS which is triggered by temperature, day length r other stimuli trigger. CNS decreased production of molt inhibiting hormones which promote release of molting hormone
how do eyestalks affect molting
accelerates it and prevent colour change to match background as eyestalk hormones control dispersal of cell pigments
what is an Endocrine Disrupting Chemical (EDCs)
a chemical that interferes with the synthesis, secretion, transport, binding, action or elimination of any hormone in the body
what are some known sources of EDCs
Pesticides, plastic leaching, drugs (e.g. birth control), industrial chemicals, household products such as detergents soaps and cleaners and, heavy metals (lead, mercury etc.)
What can EDCs link to
Reproductive disorders, immune system dysfunction, certain cancers, low iq
What is nonylphenol (NP)
added to pesticides and detergents to make chemicals work better in water. It is suspected if feminizing male fish in rivers
describe muscle physiology
macroscopic structure made of cellular and subcellular units.
In charge of body movement, respiration, heart beat, production of body heat and more
what is excitability in terms of muscle physiology
capacity of muscles to respond to a stimulus
what is contractility in terms of muscle physiology
ability of a muscle to shorten and generate pulling force
what is extensibility in terms of muscle physiology
muscle can be stretched back to its original length
what is elasticity in terms of muscle physiology
ability of muscle to recoil to original resting length after stretched
What are the 3 types of muscle
Skeletal, smooth and cardiac
describe skeletal muscles
muscles that are attached to bones. responsible for locomotion, facial expressions, respiratory movements. Controlled by somatic motor neurons
what is perimysium
collagen and elastic fibres surrounding a group of muscle fibres called a fascicle
contains blood vessels and nerves
what is endomysium
loose connective tissue that surrounds individual muscle fibres
what are sarcomere
the basic unit of contraction of skeletal muscles
what are z discs
the boundaries of each sarcomere
what are actin filaments
think filaments that extend from Z disc toward the centre of the sarcomere
what are myosin filaments
thick filaments located in the centre of the sarcomere
what are A bands
full length of the thick filaments includes inner end of thin filaments
what is the H zone
centre part of A band where no think filament occurs
What is the I band
region with only thin filaments
What is the relaxed and stimulated state of muscles
when thin and thick filaments only slightly the muscle is relaxed. Upon stimulation myosin head bin to actin and thin filaments slide past thick one so that the filament overlap to a greater degree
describe smooth muscles
grouped into sheets in walls of hollow organs. Participate in peristalsis.
what is the longitudinal layer
muscle fibres that run parallel to the organs long axis
what is the circular layer
muscle fibres that run around circumference of the organ
what are the 4 fs
Fighting, fleeing, feeding and FUCKING
Describe cardiac muscles
only found in the heart where it forms a thick layer called the myocardium.
Made of striated fibres that branch and each cell usually has one or two centrally located nuclei
What is bioelectricity
like all cellular organisms humans run on electricity. Slight imbalances of electric charge charges across membranes result in sensation, movement, awareness and thinking
What is the nervous system
translate sensory information into action potentials and process APs into adaptive response
what are the major components of the immune system
physical barriers, cells and tissues, soluble factors
What is a reflex arc
The most basic pathway
Sensory neuron controls effector cell directly
Define phagocytosis
Basic immune response evolved from feeding by protists - and underpins many immune developments and is in all animal groups
What are the three main stages of cell response
Recognition, communication, and response
define acoelomates
includes sponges, cnidarians, flatworms. They are filter feeders, carnivores or absorbers. They blood or immune system or specialized immune cells. Their threats are microbes in water
What are Fibrinogen Related Proteins (FREPs)
Highly variable proteins that are up-regulated in gastropods following parasitic infection.
The protein binds agglutinates and kills sporocysts in hemolymph
What are allogeneic interactions
Allogeneic = different genotypic individuals
their interactions can be to tolerate, to attack each other and fuse
what is a phylum
a major group of animals thought to share a common evolutionary ancestor.
Usually based on similarities in morphology, body and or similarities in development and embryology. Increasingly based on molecular evidence.
how many phyla are there
approximately 35
where are the porifera (sponges) phylum found
virtually all are found in ocean. Most are subtidal. Tend to be abundant in areas with fast currents as they are filter feeders
What do porifera look like
Usually irregular and vary variable in shape
They can be thin crusts, thick encrusting lobes, vase shaped, spherical, irregular, basket shaped.
Glass sponges have been found in deep sea
what are the characteristics of porifera
No true tissues organs, gut or nervous system.
Cells loosely aggregated and have high regenerative potential
Asymmetrical or radially symmetrical
Current flows though pores, canals and chambers throughout body
chamber lined with flagellated cells
possess an internal skeleton of spicules and or organic fibres
where are the Cnidaria (jellyfish, sea anemones, coral etc.) phylum found
virtually all found in sea
most are subtidal some found at shore
Tend to be abundant in areas with fast currents because they are filter feeders
What does Cnidaria look like
Usually radially symmetrical, Have a diverse range of body forms. Tends to be better defined than sponges
Have 2 main body forms - polyps and medusae (some species have both)
Describe polyps
A fixed cylindrical structure that symbolizes an asexual phase
many species are formed from a colony of many connected polyps (most corals)
Describe medusa
a free-swimming umbrella like structure that represents the sexual stage
What are nematocysts
Stinging cells that are one of the main features of the phylum. Venom can be highly toxic and cause fatalities
What are the Cnidaria characteristics
Mostly marine
Cell wall differentiated
Body wall is three layered
Mouth is generally surrounded by tentacles
They have two main structures (polyp and medusa)
Alteration of generations
Posses nematocysts
Describe the super-phylum Arthropoda
Chitin exoskeleton which is periodically moulted, segmented body, jointed with paired appendages
Sexes usually separated
Millions of species
Made up Chelicerata (scorpions, spiders), Uniramia (insects, millipedes and centipedes), and Crustacea (crabs, lobsters, shrimp)
Describe the Chelicerata (scorpions, spiders etc.) phylum
Made up of 3 main classes: merostomata - horseshoe crabs (4 species), arachnida - scorpions, spiders, ticks etc. (over 70,000 species) and pycnogonida - sea spiders (over 1000) species
Describe Scorpionidae order
Terrestrial present in all continents. Abudant in tropical and subtropical regions. Nocturnal, carnivorous. Uses sting which injects neurotoxins to kill prey. Over 3000 species
Describe the Araneae order
Approx. 50000 species made up of around 20 species. Mainly terrestrial. Usually predators of arthropods. Have poison glands associated with chelicera, digest prey externally and ingest fluids.
Describe Chelicera
a pair of appendages in front of the mouth in arachnids and some other arthropods, usually modified as pincer-like claws