Exam 3 Flashcards
Photomorphogensis
The effects of light on plant morphology
The Action Spectrum
It depicts relative resonses of a process to different wavelengths
Blue-Light Photoreceptors
They control hypocotyl elongation, stomata opening and phototropism
Phototropism
a plant’s response that allows plants to grow towards, or in some cases away from, a source of light
Phytochromes
pigments that regulte many of a plant’s responses to light throughought life
EX: seed germination and shade avoidence
Photoperiodism
a physiologicsl response to photoperiod (when light is availibal during the day)
Short-Day Plants
flower when the light period is shorter than a critical threshold
Long-day Plants
Flower when light period is longer than a certain number of hours
Day-neutral Plants
Flowering is controlled by a plant’s maturity not photoperiod
Florigen
The floweing signal
Gravitropism
A plants response to gravity
- Can be negative or positive
Statoliths
specilized plastids containing dense starch grains that may contribute to gravity detection
Thigmomorphogenesis
the change in form that results from mechanical disturbance (touching the plant)
Thigmotropism
The bending of a plant in response to touch
Methyljasmonic Acid
Something that can activate the expression of genes involved in plant defense
Bilateral Symmetry
Two-sided symmetry
Sagittal Plane
The dividing plane
Dorsal
The top side
- The back on humans
Ventral
The bottom side
- Stomach on humans
Posterior
The tail end
- butt on humans
Anterior
The head
- head on human
Diploblastic
Having only two germ layers
Cephalization
The development of a head
Triploblastic
Having three germ layers
- common to all bilaterally symmetric animals
Protosome
Mouth develops before the anus
Blastopore
What becomes the mouth in the protostomes
Deuterostome
Anus develops before the mouth
Zygote
single cell from fertilization
- step one
Blastula
hollow ball of cells formed by cleavage
- step two
Gastrula
embryo has one end folded inward and layers of tissue form
- step three
Ectoderm
it convers the surface and becomes the outer covering
- in some phyla it becomes the central nervous system
Endoderm
the innermost germ layer that lines the digestive tract and organs
- Lines organs such as lungs and the liver
Mesoderm
the third layer (between the other two) forming musclues and most other organs
- Not all animals have mesoderm
Coelom
fluid or air filled space separating digestive tract from the outer body wall
- Most tripoblasts have a coelom
- True coelom is formed from mesoderm
Pseudocoelomate
when the coelom is formed from both endo- and mesoderm tissue
- Roundworm
Coelomates
Animals with a true coelom
- Earthworm
Acoelomate
When a tripoblast lacks a body cavity
- EX: flatworms
Eumetazoans
A clade of animals with true tissues
- Includes the bilaterians and deuterostomia
Bilaterians
Most animal phyla that belong to the clade bilateria
Choanocyte
cells that line the interior of sponges that contain a central flagellum
* cyte- cells
Hermaphroditism
an orginism that is one sex at one time and another at a different time
Poison
something that is ingested, inhaled or absprbed into the bloodstream through contact
- dart frogs
Venom
Produced in a gland that is injected into the body, via a flesh-piercing fang, stinger, barb or spine
- scorpions
Hydrozoans
One class of the phylum cnidaria. The polyp stage is more conspicuous and they can reproduce by budding.
- Man O’ War
Budding
an asexual reproduction method in which a new organism develops from a bud of an existing organism
Scyphozoans
One class of the phylum cnidaria. The medusa is the obvious stage and they lack a polyp stage.
- most are jellies
Anthozoans
A class of the phylum cnidaria. The medusa stage is absent.
- Most are sessile (imobile)
- EX: Sea anemones and corals
Cubozoans
One class of the phylum cnidaria. They have box-shapped medusas, complex eyes, and they are highly toxic.
- box jellyfish
Tuberllarians
In the phylum platyheminthes. They are generally free living and found in marine habitats. Some can reproduce asexually by fission. They can also be hermaphrodites (a sexually reproducing organism that produces both male and female gametes)
Alimentary Canal
Seperates the mouth and anus in the phylum rotifera
Parthenogenesis
sexual reproduction in which a female can produce an embryo without fertilizing an egg with sperm
- organisms in the rotifera phylum do this
Bdelloidea
A class of rotifers that are asexual (no males)
Anhydrobiosis
the ability of organisms to lose almost all water and it becomes encysted when harsh conditions are sensed.
Mollusca
This is a phylum that is mostly marine but also fresh water and terrestrial. Some have a hard shell or no shell.
- clams
Muscular Foot
One of the three main body parts of mollusca phylum used for digging and grasping
Mantle
One of the three main body parts of mollusca phylum that is a fold of tissue over visceral mass. It creates a visceral cavity and it secretes the shell.
Radula
One of the three main body parts of mollusca phylum that is a tounge like structure used for feeding.
Gastropoda
The biggest class of molluscs. They are marine, freshwater, and terrestrial. Many of them are hermaphroditic.
- typical snails and slugs
Torsion
the ability to rotate the visceral mass around so the anus is near the head
Bivalvia
One class of molluscs where the shell is divided in two and there is no distinc head. They are filter feaders and some have eye spots and gills for gas exchange.
- EX: scallops
Chromatophores
organs that allow the orgamisms to change colors by distorting the cytoelastic sacculus (a sac containing the pigments) changing the translucency or reflectivity of the cell.
Photophores
organs that allow bioluminescent light to shine from the orgamism
Cephalopoda
One class of molluscs that are predators with complex brains and well developed sense organs. They have beak-like jaws to tear prey and a closed circulatory system. Most do not have a shell.
- EX: Octopi and squid
Annelida
A phylum that includes segmented worms that can be fresh water, marine, and terrestrial (damp environments).
- EX: earthworms
Hemolymph
a fluid that is moved by the heart into spaces around tissues and organs called sinuses
Polychaeta
A class of annelids that are free living and mostly marine.
Nematoda
A phylum in which organisms habitats include water, soil, plant, and animal tissue. They are quite small and they have no circulatory system.
- EX: Roundworms
Hirudinea
A class of annelids that are mostly freshwater parasites, predators, and detritivores
- Leeches
Arthropoda
A phylum that is big and old. There are about 1018 arthropods alive. They are the most successful animal phylum.
Cuticle
The exoskeleton covering made of chitin and proteins. This requires molting for growth, it prevents desiccation, and provides structural strength for animals on land.
- exoskeletons are a limiting factor because they don’t allow the organism to get very big
Sensory Organs
Eyes, smell receptors, and antennae for touch and smell
Arthropod body plan
consists of a segmented body, a hard exoskeleton, and jointed appendages
Chelicerae
Fangs which are a characteristic of the subphylum cheliceriformes (spiders, mites, and scorpions)
Homeotic Genes
Sequences in the genome that provied location information
- In plants: MADS-box genes
- In animals: HOX or HOM genes
Cephalothorax
One of the two parts of the subphylum cheliceriformes body
Arachnids
The largest group of the subphylum cheliceriformes
- EX: scorpions, spiders, ticks, and mites
Abdomen
One of the two parts of the subphylum cheliceriformes body
Pedipalps
Modified limb that arachnids have that is used for sensing, feeding and reproducing.
Complete Metamorphosis
Specialized larval stage that looks different from adult
- EX: caterpillar into butterfly
Insects
are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals
Imcomplete Metamorphosis
When the young (nymphs) resemble the adults and they molt making the nymphs look more adult. When they undergo the final molt it produces sexual maturity and wings.
- The young stage looks like little adults
- EX: Grasshopers
Coleoptera
One order of insect. They are beetles
- 350,000 species
- Complete Metamorphosis
Diptera
One class of inscects that include flies and mosquitoes
- 151,000 species
- Complete Metamorphosis
Hymenoptera
One class of inscects that include ants, bees, and wasps
- 125,000 species
- Social insects
- Complete Metamorphosis
Orthoptera
One class of inscects that include grasshoppers, crickets, and katydids
- 20,000+ species
- Incomplete metamorphosis
Isopods
In the subphylum crustacea.
- they include wood lice and many other species
- They are terrestrial, marine, and fresh water
Decapods
In the subphylum crustacea that have a carapace that is a hardened cutical on the dorsal cephalothorax (thick shell like structure)
- Include lobsters, crabs and shrimp
Copepods
In the subphylum crustacea.
- Include krill and other species
- Planktonic crustaceans
Chordates
bilaterian animals that belong to the clade of animals known as deuterostomia
Vertebrates
animals that have a backbone
What are the four main characteristics of chordates?
- Notochord
- Dorsal, hollow nerve cord
- Pharyngeal slits or clefts
- Muscular, post-anal tail
Notochord
a longitudinal, flexible rod between the digestive tube and nerve cord that provides skeletal support.
- In most vertebrates, a more complex, jointed skeloton develops
Nerve Cord
develops from a plate of ectoderm that rolls into a tube dorsal to the notochord
- develops into the central nervous system
Pharyngeal clefts
develop into slits that open to the outside of the body. They are used for suspension-feeding (filter feeding) and gas exhcange.
- They develop into head, ear and neck in tetrapods
Post-anal tail
In many species the tail is greatly reduced (frogs and toads loose their tails) during development. It provides propelling force in many aquatic species and in terrestrial organisms it provides balance.
Lancelets
they are marine suspension feeders named for their bladelike shape
- they are chordates but not vertebrates
- they retain the chordate body plan as adults
Tunicates
A specices of marine suspension feeders more closly related to the chordates than the lancelets
- they are blob like and lack structure
Craniates
Organisms that share characteristics like a skull (at least a partial skull), brain, eyes, and other sensory organisms.
- not all have ears
Neural Crest
a collection of cells near the dorsal margins of the closing neural tube in an embryo. They give rise to a variety of structures including some of the bones and cartilage of the skull
- This is a derived characeristic of craniates
- Craniates have a heart with at least two chambers, red blood cells, and kidneys
Gnathostomes
vertebrates with jaws
Gnath= Jaw
Stome= Opening
Lateral Line System
Used to sense vibrations in aquatic gnathostomes
Chondrichthyans
organisms that have skeleton composed primarily of cartilage
- Chondri= cartilage
- Thyes= fish
- EX: sharks and rays
Oviparous
eggs that hatch outside the mothers body
Ovoviviparous
the embryo develops withing the uterus and is nourished by the egg yolk
- the egg yolk nourishes the embryo not the mother
- hatches inside the mother
Viviparous
the embryo develops within the uterus and is nourished through a yolk sac placenta from the mother’s blood
- the most similar to mammals but a bit different
Osteichthyes
includes the bony fish and tetrapods. nearly all living have a bony endoskeleton
- Ostei= bone
- Thyes= fish
Operculum
a covering over fishes gills that protect them when drawing water over their gills to breath
Swim Bladder
how fish control their buoyancy
- its an air sac they can use to rise or lower their buoyancy
Lobe-fins
A type of clade of sarcopterygii that have muscular pelvic and pectoral fins
Tetrapods
a group of vertebrates that have four limbs that can be fully aquatic, fully terrestrial, or both.
- Tetra= four
Derived Characters of tetrapods
- four limbs and feet with digits (toes and fingers)
- Ears for detecting airborne sounds
Amphibians
They have an aquatic larva that develops into a terrestrial adult. Most have moist skin that complements the lungs in gas exchange. In most species fertilization happens external to the body.
- 6150 species
- Three orders
Caudata
One of the orders of amphibian that includes salamanders
- they have tails
Anura
One order of amphibian that includes frogs and toads
- they lack a tail
Apoda
One order of amphibian that includes caecilians
- they are legless and resemble worms but they have a skeleton
- A= no
- Poda= limbs
Amniotes
A group of tetrapods whoes living members are the reptiles, including birds and mammals
Amniotic Egg
contains membranes that protect the embryo. It has relativly impermeable skin and the ability to use the rib cage to ventilate the lungs.
Reptilia
a clade of amniotes that includes lizards, snakes, turtles, crocodilians, birds and dinosaurs.
Derives Characters…
* scales that creates a waterproof barrier
* they lay shelled eggs on land
Ectothermic
absorb external heat as the main source of bady heat
- most reptiles
Endothermic
Capable of keeping the body warm through metabolism
- birds and mammals
Squamata
includes lizards and snakes
Archosaur
a lineage that produces the crocodilians, pterosaurs, and dinosaurs
Mammalia
a class including mammals represented by more than 5300 species.
Derived Characters:
* mammary glands (produce milk)
* Hair
* A larger brain than other vertebrates of the same size
* Differentiated teeth
Monotremes
small group of egg-laying mammals consisting of echidnas and the platypus
Marsupials
Organisms where the enbryo develops within the placenta in the mother’s uterus and are born early and finish development while nursing in a maternal pouch called marsupium
- EX: Opossums, kangaroos, and koalas
Eutherians
compared to marsupials they have a longer period of pregnancy. Young complete their development within the uterus, joined to the mother by the placenta.
* EX: elephants
Primates
An order of mammalian that includes lemurs, monkeys, and apes.
- Humans are members of the ape group
Paleoanthropology
The study of human origins
Hominids
more closely related to humans than chimps. they originated in africa and they had a smaller brain but most likely walked upright
Anatomy
the study of the biological form of an organism
- form
Physiology
The study of the biological functions an organism performs
- function
Environmental Relationships and Body Forms
Size and shape affect the way an animals interacts with its environment
Intersitial Fluid
fills the space between the cells which allows for the movement of material into and out of cells
- vertebrates
Tissues
organization of specilized cells that have different functions
Organs
groups of tissue that make up organ systems
Epithelial Tissue
covers the outside of the body and lines the organs and cavaties within the body. There are different shapes (cuboidal [cube like], columnar [like bricks], and squamous [like floor tials]) that have different functions. They can also be arranged different ways like simple [single cell layer], stratified [multi tier], and pseudostratified [single layer of uneven thickness].
- Epi= outer
Fibroblasts
a type of proper connective tissue that produce and secrete extracellular matrix
- EX: collagen, elastin, and reticulin
Loose connective tissue
binds epithelia to underlying tissues and holds organs in place
*EX: Adipose tissue- stoes fat for insulation and fuel
Dense connective tissue
found in tendons which attach muscules to bones, and ligaments which connect bones at joints
Special Connective Tissue
- Cartilage- a strong and flexible support material
- Blood- composed of blood cells and cell fragments in blood plasma
- Bone- collagen and hydroxyapatite and forms the skeleton
Osteoblasts
cells that form the bone
- Osteo=bone
- Blast= cells
Joints
allow movement in animals. There are many different kinds like…
1. Ball and Socket (hips)
2. Hinge (elbow)
3. Gliding (vertebral projections)
4. Combination (human jaws)
Muscle Tissue
consists of long cells called muscle fibers, which contract in response to nerve signals. There are three types…
1. Skeletal muscule- responsible for voluntary movement
2. Smooth muscule- responsible for involuntary body activities
3. Cardiact muscules- responsible for contraction of the heart
Nervous Tissue
senses stimuli and transmits signals throughout the animal.
Neurons
part of the nervous tissue that transmits nerve impulses
Neuroglial cells
part of the nervous tissue that help nourish, insulatem and replenish neurons
Hormones
the chemical signals that the endocrine system transmits to receptive cells throughout the body via blood
Regulator
uses internal control mechanisms to moderate internal change in the face of external, environmental fluctuation
Conformer
allows its internal conditions to vary with certain external changes
Homeostasis
what organisms use to maintain a “steady state” or internal balance regardless of external environment
- EX: humans maintain a constant body temp
Negative Feedback
what homeostasis is maintained by which helps to return a variable to either a normal range or a set point
Positive Feedbck
loops that occur in animals but do not usally contribute to homeostasis
Acclimatization
a process where homeostasis can adjust to changes in external environment
Thermoregulation
the process by which animals maintain an internal temp within a tolerable range
Endothermic
animals generate heat by metabolism
- EX: birds and mammals
Ectothermic
animals gain heat from external sources
- EX: most invertebrates, fishes, amphibians, and non-avian reptiles
Conduction
the gaining or lossing of heat through direct contact with an object
Convection
gaining or losing heat by moving air or water of a different temperature over the animal
Radiation
the emission of electromagnetic “heat” waves
- EX: the sun
Evaperation
it removes heat and can act as a cooling mechanism
Integumentary system
skin, hair, and nails
Insulation
a major thermoregulatory adaptation in mammals and birds
- EX: skin, feathers, fur, and blubber
Vasodilation
this facilitates heat loss by increasing the blood flowing in the skin
- EX: alcohol- it dilates blood vessels on the surface and cools the body
Vasoconstriction
lowers heat loss by decreasing blood flow in the skin
Countercurrent Exchange
the arrangement of blood vessels in many marine mammals and birds that transfers heat between fluids flowing in opposite directions.
Hypothalamus
controls mammalian thermoregulation
