Fungi, Animal Phylogeny, and Homeostasis: Key Concepts for Biology

Chitin

A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.

Hyphae

The branching, threadlike tubes that make up the bodies of multicellular fungi

Septa

the cells that make up hyphae are divided by these cross sections

Mycorrhizae

Ecological relationship between the mycelium of a fungus and the roots of certain plants

fruting bodies

fungi produce spores in reproductive structures

yeast

unicellular fungi

Symbiosis

A close relationship between two species that benefits at least one of the species.

faculative

can live with or without oxygen

obligate anaerobes

organisms that cannot live where molecular oxygen is present

Mutualism

A relationship between two species in which both species benefit

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed

competition

the struggle between organisms to survive in a habitat with limited resources

Predation

An interaction in which one organism kills another for food.

Herbivory

interaction in which one animal (the herbivore) feeds on producers (such as plants)

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected

Choanoflagellates

protists that are the closest living relatives of animals

Cambrian

The first period of the oldest era on the geologic time scale.

Edicaran

First true community- things lived in different niches, no predators here yet- life is still simple

Porifera

sponges

cnidaria

jellyfish, corals, sea anemones

germ layers

Three main layers that form the various tissues and organs of an animal body.

Bilateria

animals with bilateral symmetry

protosomes

blastopore becomes mouth

Deuterostomes

blastopore becomes anus

homeobox

a DNA sequence within a homeotic gene that regulates development in animals

adaptive radiation

An evolutionary pattern in which many species evolve from a single ancestral species

Anatomy and Physiology

Structure or function of the body/ working system

surface area to volume ratio

a variable that decreases as cells grow, so that it sets a limit to the size of cells.

metabolic rate

Amount of energy an animal uses in a unit of time; the sum of all the energy-requiring biochemical reactions.

conformers vs regulators

- Twp evolutionary paths for organisms

- Regulate internal environment: maintain relatively constant internal conditions

- Conform to external environment: allow internal conditions to fluctuate along with external changes

Ectotherms vs. Endotherms

"cold-blooded" vs. "warm-blooded"

Homeotherm vs poikilotherm

Homeotherm- Same body temp

Poikilotherm- Varying body temps with environment

set point

the point at which one's body tries maintain

sensor

in homeostasis, a receptor that detects a stimulus

Integrator

compares signals from the sensor to set point

Effector

an organ or cell that acts in response to a stimulus.

negative feedback

A primary mechanism of homeostasis, whereby a change in a physiological variable that is being monitored triggers a response that counteracts the initial fluctuation.

positive feedback

Feedback that tends to magnify a process or increase its output.

Ecdysis

molting

chelicerae

pair of mouthparts in chelicerates that contain fangs and are used to stab and paralyze prey

myriapods

centipedes and millipedes

Crustaceans

Shells soft bodies, no vertebra &Hard shells.

Hexapods

insects - 3 body regions (head:antannae, mandibles - thorax: 3 pairs of walking legs - abdomen: no appendages), most abundant and diverse, herbivores, detrivores, fluid drinkers, predators, scavengers, parasites

Segmentation

the division of the body of an organism into a series of similar parts

exoskeleton

A body covering, typically made of chitin, that provides support and protection

open circulatory system

A circulatory system that allows the blood to flow out of the blood vessels and into various body cavities so that the cells are in direct contact with the blood

tracheal system

In insects, a system of branched, air-filled tubes that extends throughout the body and carries oxygen directly to cells.

Spermatophore

A gelatinous package of sperm cells that is produced by males of species that have internal fertilization without copulation.

metamorphosis

change of form

Chordates

an animal phylum that has a notochord, a dorsal hollow nerve cord, and gill slits at some time in its life cycle

dorsal hollow nerve cord

nerve cord found in all chordates that forms the spinal cord and brain

postanal tail

muscular structure at the end of a developing chordate

pharyngeal slit

an opening in the pharynx

countercurrent flow vs concurrent flow

Countercurrent: When water has a 100% oxygen concentration when it first enters the gills while the blood flow through the lamellae only has 90% oxygen during to flowing the opposite way. As water continues to flow over the lamellae it progressively loses 10% oxygen to blood due to being picked up by capillaries. But at the end water still has more oxygen than blood.

-Concurrent - when water and blood flow in the same direction. Water starts off with 100% oxygen and blood starts with 0%. Diffusion will occur but then stop due to equilibrium and there will be more no oxygen uptake

amniotic

Pertaining to sac holding the fetus and fluid

Tinbergen's 4 questions

1. causation

2. development

3. function

4. evolution

Proximate vs Ultimate

Proximate-how, biological

Ultimate-why, evolutionary

Ontogeny

development of individual

fixed action pattern

a sequence of unlearned acts directly linked to a simple stimulus

Communication

The imparting or exchanging of information or news

honest signal

trait that gives a truthful impression of an individual's fitness

intersexual selection vs intrasexual selection

1. Intersexual Selection - favors traits that make one sex (usually males) more attractive to the opp sex (usually females)

2. Intrasexual Selection - favors traits that make members of one sex (usually males) successful in competition w/ each other

Anisogamy

Refers to a difference in gamete size in males and females. Eggs large and costly, sperm small and cheap

secondary sex characteristics

nonreproductive sexual characteristics, such as female breasts and hips, male voice quality, and body hair

monogamy, polygamy, polygyny, polyandry

Monogamy-one spouse

Polygamy-multiple spouses

Polygyny-multiple wives

Polyandry-multiple husbands

Adducted big toe

A big toe, or great toe, that is close to the second toe; compare with abducted.

Australopithecus

the earliest humanlike creature that flourished in eastern and southern Africa 3 to 4 million years ago

Hominin

humans and humanlike ancestors

Homo sapiens

humans

background extinction

gradual process of a species becoming extinct

mass extinction

event in which many types of living things become extinct at the same time

Anthropocene

the modern geological era during which humans have dramatically affected the environment

ecosystem services

the processes by which life-supporting resources such as clean water, timber, fisheries, and agricultural crops are produced

Biodiversity

the variety of life in the world or in a particular habitat or ecosystem.