Transcript Fungi Chapter 31 • Overview: Mighty Mushrooms • Fungi – Are diverse and widespread – Are essential for the well-being of most terrestrial ecosystems because.

Fungi Chapter 31
• Overview: Mighty Mushrooms
• Fungi
– Are diverse and widespread
– Are essential for the well-being of most terrestrial
ecosystems because they break down organic
material and recycle vital nutrients
Figure 31.1
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Decomposers
• Fungi are well adapted as decomposers of
organic material
– Performing essential recycling of chemical
elements between the living and nonliving
world
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Nutrition
Despite their diversity
– Fungi share some key traits
• Fungi are heterotrophs
– But do not ingest their food
• Fungi secrete into their surroundings
exoenzymes that break down complex
molecules
– And then absorb the remaining smaller
compounds
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• Fungi exhibit diverse lifestyles
– Decomposers
– Parasites
– Mutualistic symbionts
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• Fungi consist of
– Mycelia, networks of branched hyphae
adapted for absorption
• Most fungi
– Have cell walls made of chitin
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Body Structure
• The morphology of multicellular fungi
– Enhances their ability to absorb nutrients from
their surroundings
Reproductive structure.
The mushroom produces
tiny cells called spores.
Hyphae. The mushroom and its
subterranean mycelium are a
continuous network of hyphae.
Spore-producing
structures
20 m
Figure 31.2
Mycelium
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• Some fungi
– Have hyphae divided into cells by septa, with
pores allowing cell-to-cell movement of
materials
• Coenocytic fungi
– Lack septa
Cell wall
Cell wall
Nuclei
Pore
Septum
Figure 31.3a, b
(a) Septate hypha
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Nuclei
(b) Coenocytic hypha
• Some unique fungi
– Have specialized hyphae that allow them to
penetrate the tissues of their host
Nematode
Hyphae
25 m
(a) Hyphae adapted for trapping and killing prey
Plant
cell
wall
Fungal hypha
(b) Haustoria
Haustorium
Figure 31.4a, b
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Plant cell
Plant cell
plasma
membrane
• Fungi produce spores through sexual or
asexual life cycles
• Fungi propagate themselves
– By producing vast numbers of spores, either
sexually or asexually
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• The generalized life cycle of fungi
Key
Heterokaryotic
stage
Haploid (n)
Heterokaryotic
(unfused nuclei from
different parents)
PLASMOGAMY
(fusion of cytoplasm)
Diploid (2n)
KARYOGAMY
(fusion of nuclei)
Spore-producing
structures
Spores
SEXUAL
REPRODUCTION
ASEXUAL
REPRODUCTION
Zygote
Mycelium
MEIOSIS
GERMINATION
GERMINATION
Spore-producing
structures
Spores
Figure 31.5
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Sexual Reproduction
• The sexual life cycle involves
– Cell fusion, plasmogamy
– Nuclear fusion, karyogamy
• An intervening heterokaryotic stage
– Occurs between plasmogamy and karyogamy
in which cells have haploid nuclei from two
parents
• The diploid phase following karyogamy
– Is short-lived and undergoes meiosis,
producing haploid spores
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• Many fungi that can reproduce asexually
– Grow as mold, sometimes on fruit, bread, and
other foods
2.5 m
Figure 31.6
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• Other asexual fungi are yeasts
– That inhabit moist environments
– Which produce by simple cell division
10 m
Parent cell
Bud
Figure 31.7
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• Many molds and yeasts have no known sexual
stage
– Mycologists have traditionally called these
deuteromycetes, or imperfect fungi
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• Fungi descended from an aquatic, singlecelled, flagellated protist
• Systematists now recognize Fungi and
Animalia as sister kingdoms
– Because fungi and animals are more closely
related to each other than they are to plants or
other eukaryotes
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The Origin of Fungi
• Molecular evidence
– Supports the hypothesis that fungi and animals
diverged from a common ancestor that was
unicellular and bore flagella
• Fungi probably evolved
– Before the colonization of land by multicellular
organisms
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• The oldest undisputed fossils of fungi
– Are only about 460 million years old
50 m
Figure 31.8
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Arbuscular
mycorrhizal
fungi
Sac
fungi
Club
fungi
Ascomycota
Basidiomycota
Zygomycota
Chytridiomycota
Zygote
fungi
Chytrids
Glomeromycota
• The phylogeny of fungi
Figure 31.9
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• A review of fungal phyla
Table 31.1
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Symbionts
• Fungi form symbiotic relationships with
– Plants, algae, and animals
• Mycorrhizae
– Are mutually beneficial relationships
between fungi and plant roots
– 90% of all plant species have
mycorrhizae relationships with fungi.
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The Move to Land
• Fungi were among the earliest colonizers of
land
– Probably as symbionts with early land plants
– The mycorrhizal symbiosis often increases the
plant's uptake of inorganic compounds, such
as nitrate and phosphate from soils
– The fungal partners may also mediate plantto-plant transfer of carbohydrates and other
nutrients.
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Mycorrhizae
• Mycorrhizae
– Are enormously important in natural
ecosystems and agriculture
– Increase plant productivity
EXPERIMENT Researchers grew soybean plants in soil treated with fungicide (poison that kills fungi) to
prevent the formation of mycorrhizae in the experimental group. A control group was exposed to fungi that formed
mycorrhizae in the soybean plants’ roots.
RESULTS
The soybean plant on the left is typical of the experimental group. Its
RESULTS
stunted growth is probably due to a phosphorus deficiency. The taller, healthier plant on
the right is typical of the control group and has mycorrhizae.
Figure 31.21
CONCLUSION
These results indicate that the presence of mycorrhizae benefits a soybean
plant and support the hypothesis that mycorrhizae enhance the plant’s ability to take up
phosphate and other needed minerals.
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Fungus-Animal Symbiosis
• Some fungi share their digestive services with
animals
– Helping break down plant material in the guts
of cows and other grazing mammals
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• Many species of ants and termites
– Take advantage of the digestive power of fungi
by raising them in “farms”
Figure 31.22
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Lichens
• Lichens
– Are a symbiotic association of millions of
photosynthetic microorganisms held in a mass
of fungal hyphae
(a) A fruticose (shrub-like) lichen
Figure 31.23a–c
(b) A foliose (leaf-like) lichen
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(c) Crustose (crust-like) lichens
• The fungal component of a lichen
– Is most often an ascomycete
• Algae or cyanobacteria
– Occupy an inner layer below the lichen surface
Ascocarp of fungus
Soredia
Fungal
hyphae
Algal
layer
Algal cell
Figure 31.24
10 m
Fungal hyphae
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Pathogens
• About 30% of known fungal species
– Are parasites, mostly on or in plants
Figure 31.25a–c
(a) Corn smut on corn
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(b) Tar spot fungus on maple leaves
(c) Ergots on rye
Practical Uses of Fungi
• Some of the fungi that attack food crops
– Are toxic to humans
• Genetic research on fungi
– Is leading to applications in biotechnology
• Humans eat many fungi
– And use others to make cheeses, alcoholic
beverages, and bread
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• Antibiotics produced by fungi
– Treat bacterial infections
Staphylococcus
Penicillium
Zone of
inhibited
growth
Figure 31.26
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Chapter 33 Invertebrates
• Overview: Life Without a Backbone
• Invertebrates
– Are animals that lack a backbone
– Account for 95% of known animal species
Figure 33.1
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How Animals are Built
• Nearly all animals follow a physical plan. There
are three kinds.
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Asymmetry
The
arrangement of
body parts
without central
axis or point.
• Asymmetrical
organisms do not
develop complex
communication,
sensory or motor
functions
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Radial Symmetry
• The arrangement of
body parts such that
any plane passing
through the oralaboral axis divides
the animal into mirror
images
• Allows for better
specialization of
sensory feeding and
motor structure
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Bilateral Symmetry
• The arrangement of
body parts such that a
single plane passing
through the oral-aboral
axis divides the animal
into mirror images
• Allows for advanced
specialization of
sensory, feeding and
motor function which
usually occurs in a
distinct head
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Chordata
Echinodermata
Other bilaterians (including
Nematoda, Arthropoda,
Mollusca, and Annelida)
Porifera
Cnidaria
• A review of animal phylogeny
Deuterostomia
Bilateria
Eumetazoa
Ancestral colonial
choanoflagellate
Figure 33.2
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Phylum Porifera
• Sponges are sessile and have a porous body
and choanocytes
• Cellular – lack tissue
sponges have no germ layers, no symmetry,
no cephalization, no body cavity, and no
segmentation
• Reproduce sexually or asexually
5000 known species
• Sponges, phylum Porifera
– Live in both fresh and marine waters
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• Sponges are suspension feeders
– Capturing food particles suspended in the
water that passes through their body
5 Choanocytes. The spongocoel
is lined with feeding cells called
choanocytes. By beating flagella,
the choanocytes create a current that
draws water in through the porocytes.
Azure vase sponge (Callyspongia
plicifera)
4 Spongocoel. Water
passing through porocytes
enters a cavity called the
spongocoel.
3 Porocytes. Water enters
the epidermis through
channels formed by
porocytes, doughnut-shaped
cells that span the body wall.
2 Epidermis. The outer
layer consists of tightly
packed epidermal cells.
Figure 33.4
Flagellum
Collar
Food particles
in mucus
Choanocyte
Osculum
Phagocytosis of
food particles
Spicules
Water
flow
1 Mesohyl. The wall of this
simple sponge consists of
two layers of cells separated
by a gelatinous matrix, the
mesohyl (“middle matter”).
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Amoebocyte
6 The movement of the choanocyte
flagella also draws water through its
collar of fingerlike projections. Food
particles are trapped in the mucus
coating the projections, engulfed by
phagocytosis, and either digested or
transferred to amoebocytes.
7 Amoebocyte. Amoebocytes
transport nutrients to other cells of
the sponge body and also produce
materials for skeletal fibers (spicules).
Phylum Cnidaria
• Jellyfish, sea anemones, coral
• Radial symmetry
- polyps & medusa
• Bodies contain
“jelly” (mesoglea)
• Specialized
stinging cells
Sea Anemone
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• Tissue - lack organs
have radial symmetry and 2 germ layers
• lack cephalization, body cavity, & segmentation
• Reproduce sexually or asexually
11,000 known species
4 groups - hydroids, box jellyfish, jellyfish,
corals/anemones
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• The basic body plan of a cnidarian
– Is a sac with a central digestive compartment,
the gastrovascular cavity
• A single opening
– Functions as both mouth and anus
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• There are two variations on this body plan
– The sessile polyp and the floating medusa
Polyp
Medusa
Mouth/anus
Tentacle
Gastrovascular
cavity
Gastrodermis
Mesoglea
Body
stalk
Epidermis
Tentacle
Mouth/anus
Figure 33.5
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• Cnidarians are carnivores
– That use tentacles to capture prey
• The tentacles are armed with cnidocytes
– Unique cells that function in defense and the
capture of prey
Prey
Tentacle
“Trigger”
Discharge
Of thread
Nematocyst
Figure 33.6
Coiled thread
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Cnidocyte
– Hydrozoa, Scyphozoa, Cubozoa, and
Anthozoa
–
http://bcs.whfreeman.com/thelifewire/content/chp32/32020.html
(a) These colonial polyps are members of
class Hydrozoa.
(b) Many species of jellies (class
Scyphozoa), including the
species pictured here, are
bioluminescent. The largest
scyphozoans have tentacles
more than 100 m long
dangling from a bell-shaped
body up to 2 m in diameter.
Figure 33.7a–d
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(c) The sea wasp (Chironex
fleckeri) is a member of
class Cubozoa. Its poison,
which can subdue fish and
other large prey, is more
potent than cobra venom.
(d) Sea anemones and other
members of class Anthozoa
exist only as polyps.
• Most animals have bilateral symmetry
• The vast majority of animal species belong to
the clade Bilateria
– Which consists of animals with bilateral
symmetry and triploblastic development
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Phylum Platyhelminthes
• Free living flatworms, tapeworms, flukes
• Well defined nervous,
muscular, excretory,
and reproductive
systems
• Many species have
parasitic life style
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Tapeworm
Platyhelminthes
• Have Organ system
• Platyhelminthes have bilateral symmetry and 3
germ layers
• Cephalization
• Lack body cavity and segmentation
• Reproduce sexually and a sexually
• Flat body allows for gas exchange, must
occupy wet environments
Examples - tapeworms, flukes (both
endoparasites)
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Turbellarian
• Turbellarians
– Are nearly all free-living and mostly marine
Figure 33.9
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• The best-known turbellarians, commonly called
planarians
– Have light-sensitive eyespots and centralized
nerve nets
Pharynx. The mouth is at the
tip of a muscular pharynx that
extends from the animal’s
ventral side. Digestive juices
are spilled onto prey, and the
pharynx sucks small pieces of
food into the gastrovascular
cavity, where digestion continues.
Digestion is completed within
the cells lining the gastrovascular cavity, which has
three branches, each with
fine subbranches that provide an extensive surface area.
Undigested wastes
are egested
through the mouth.
Gastrovascular
cavity
Eyespots
Figure 33.10
Ganglia. Located at the anterior end
of the worm, near the main sources
of sensory input, is a pair of ganglia,
dense clusters of nerve cells.
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Ventral nerve cords. From
the ganglia, a pair of
ventral nerve cords runs
the length of the body.
• Trematodes that parasitize humans
– Spend part of their lives in snail hosts
1 Mature flukes live in the blood vessels of the human
intestine. A female fluke fits into a groove running
the length of the larger male’s body, as shown in
the light micrograph at right.
Male
Female
1 mm
5 These larvae penetrate
the skin and blood
vessels of humans
working in irrigated
fields contaminated
with infected human
feces.
2 Blood flukes reproduce
sexually in the human host.
The fertilized eggs exit the
host in feces.
3 The eggs develop in
water into ciliated
larvae. These larvae
infect snails, the
intermediate hosts.
Figure 33.11
4 Asexual reproduction
within a snail results in
another type of motile
larva, which escapes from
the snail host.
Snail host
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Phylum Mollusca
• Large phylum with over 50,000 species
• Snails, limpets, slugs,
sea hares, mussels,
oysters, squid, octopus
• Species often have a
muscular foot, a mantle,
and a shell
Snail
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Mollusca
• Organ System
• Mollusca have bilateral symmetry and 3 germ
layers
• Cephalization
• Coelom
• No segmentation
• Sexual (some hermaphroditic)
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• All molluscs have a similar body plan with three
main parts
– A muscular foot
– A visceral mass
– A mantle
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Gastropods
• About three-quarters of all living species of
molluscs
– Belong to class Gastropoda
(a) A land snail
Figure 33.18a, b
(b) A sea slug. Nudibranchs, or sea slugs, lost their shell
during their evolution.
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Cephalopods
• Class Cephalopoda includes squids and
octopuses
– Carnivores with beak-like jaws surrounded by
tentacles of their modified foot
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Cephalopods
• Most octopuses
– Creep along the sea floor in search of prey
– https://www.youtube.com/watch?v=AP_dpbTb
ess&feature=related
Figure 33.22a
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(a) Octopuses are considered among the
most intelligent invertebrates.
• Squids use their siphon
– To fire a jet of water, which allows them to
swim very quickly
Figure 33.22b
(b) Squids are speedy carnivores with
beaklike jaws and well-developed eyes.
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Bivalves
• Molluscs of class Bivalvia
– Include many species of clams, oysters,
mussels, and scallops
– Have a shell divided into two halves
Figure 33.20
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Phylum Annelida
• Earthworms, featherdusters, leeches
• Elongate cylindrical
bodies in a series
of segments
• Well developed
organ systems
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Leech
Annelida
• Organ System
• Annelida have bilateral symmetry and 3 germ
layers
• Cephalization
• Coelom and segmentation
• Sexual reproduction (hermaphroditic)
16,500 known specices
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Annelida
• Hydrostatic Skeleton
• Circulatory system with 5 hearts
• Excretory system including Nephridia
• Nervous system has ganglionic brain and
repeating ganglia
• Digestive system is tubular gut with specialized
parts
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• Earthworms eat their way through the soil,
extracting nutrients as the soil moves through
the alimentary canal
– Which helps till the earth, making earthworms
valuable to farmers
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Leeches
• Members of class Hirudinea
– Are blood-sucking parasites, such as leeches
– Used in medicinal
purposes
release Anesthetic and
Anticoagulant at site of bite
Figure
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33.25
Phylum Arthropoda
• Hugely diverse and numerous
phylum with over a million
species
• Have a tough exoskeleton
• Jointed appendages and
segmented body plan
• Crabs, barnacles, insects,
spiders, shrimp, centipedes
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Lobster
• Organ System
• Arthropoda have bilateral symmetry and 3
germ layers
• Cephalization
• Coelom
• Segmentation
• Sexual
1,000,000 known species
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Evolution of Arthropods
• A hard exoskeleton
• Presence of jointed appendages
a complex nervous system with a brain
connected to a ventral solid nerve cord
• A unique respiratory system that emplys a
variety of respiratory organs
• A complex, yet adaptable,life cycle
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• Early arthropods, such as trilobites
– Showed little variation from segment to
segment
Figure 33.28
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General Characteristics of Arthropods
• The diversity and success of arthropods
– Are largely related to their segmentation, hard
exoskeleton, and jointed appendages
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• As arthropods evolved
– The segments fused, and the appendages
became more specialized
• The appendages of some living arthropods
– Are modified for many different functions
Cephalothorax Abdomen
Antennae
(sensory
reception)
Head Thorax
Swimming
appendages
Walking legs
Figure 33.29
Pincer (defense) Mouthparts (feeding)
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• Millipedes, class Diplopoda
– Have a large number of legs
• Each trunk segment
– Has two pairs of legs
Figure 33.33
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• Centipedes, class Chilopoda
– Are carnivores with jaw-like mandibles
– Have one pair of legs per trunk segment
Figure 33.34
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Cheliceriforms
• Cheliceriforms, subphylum Cheliceriformes
– Are named for clawlike feeding appendages
called chelicerae
– Include spiders, ticks, mites, scorpions, and
horseshoe crabs
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• Lack antennae
• Chelicerata - distintive mouth parts
• Many capture and sting insect prey
• Others are ectoparisites
• Horseshoe crabs feed on detritous
• protosomes
• Sexual reproduction only
70,000 species
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• Most of the marine cheliceriforms are extinct
– But some species survive today, including the
horseshoe crabs
Figure 33.30
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• Most modern cheliceriforms are arachnids
– A group that includes spiders, scorpions, ticks,
and mites
50 µm
(a) Scorpions have pedipalps that are pincers (b) Dust mites are ubiquitous scavengers in (c) Web-building spiders are generally
specialized for defense and the capture of
human dwellings but are harmless except
most active during the daytime.
food. The tip of the tail bears a poisonous
to those people who are allergic to them
stinger.
(colorized SEM).
Figure 33.31a–c
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Arachnids
• Lack antennae
• Cephalothorax and abdomen
• Eight Walking legs
• Carnivorous - liquid diet of bood or predigested
prey
• Simple eyes each with a single lens
many spiders have eight eyes
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• Arachnids have an abdomen and a
cephalothorax
– Which has six pairs of appendages, the most
anterior of which are the chelicerae
Intestine
Digestive
gland
Stomach
Heart
Brain
Eyes
Poison
gland
Ovary
Anus
Book lung
Spinnerets
Figure 33.32
Silk gland
Sperm
Gonopore
(exit for eggs) receptacle
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Chelicera
Pedipalp
Insects
• Subphylum Hexapoda, insects and their
relatives
– Are more species-rich than all other forms of
life combined
– Live in almost every terrestrial habitat and in
fresh water
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• Many insects have some thoracic appendages
modified for flight
• Insects have a single pair of antenna, three
pairs of legs, and in many cases, two wings
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• The internal anatomy of an insect
– Includes several complex organ systems
The insect body has three regions: head,
thorax, and abdomen. The segmentation
of the thorax and abdomen are obvious,
but the segments that form the head are fused.
Abdomen
Thorax
Head
Compound eye
Heart. The
insect heart
drives hemolymph
through an
open circulatory
system.
Cerebral ganglion. The two nerve
cords meet in the head, where the
ganglia of several anterior segments
are fused into a cerebral ganglion
(brain). The antennae, eyes, and
other sense organs are concentrated
on the head.
Antennae
Ovary
Figure 33.35
Malpighian tubules.
Anus
Metabolic wastes are
removed from the
Vagina
hemolymph by excretory
organs called Malpighian
tubules, which are outpocketings of the
digestive tract.
Tracheal tubes. Gas exchange in insects is
accomplished by a tracheal system of branched,
chitin-lined tubes that infiltrate the body and
carry oxygen directly to cells. The tracheal
system opens to the outside of the body
through spiracles, pores that can control air
flow and water loss by opening or closing.
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Nerve cords. The insect
nervous system
consists of a pair of
ventral nerve cords
with several
segmental ganglia.
Dorsal
artery
Crop
Insect mouthparts are formed from
several pairs of modified appendages.
The mouthparts include mandibles,
which grasshoppers use for chewing.
In other insects, mouthparts are
specialized for lapping, piercing, or
sucking.
• Flight is obviously one key to the great success
of insects
• An animal that can fly
– Can escape predators, find food, and disperse
to new habitats much faster than organisms
that can only crawl
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• Many insects
– Undergo metamorphosis during their
development
• In incomplete metamorphosis, the young,
called nymphs
– Resemble adults but are smaller and go
through a series of molts until they reach full
size
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• Insects with complete metamorphosis
– Have larval stages specialized for eating and
growing that are known by such names as
maggot, grub, or caterpillar
• The larval stage
– Looks entirely different from the adult stage
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• Metamorphosis from the larval stage to the
adult stage
– Occurs during a pupal stage
(a) Larva (caterpillar)
(b) Pupa
(c) Pupa
(d) Emerging adult
Figure 33.6a–e
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(e) Adult
Ecological Role of Insects
• Pollination
• decomposition of organic material
• recycling of carbon, nitrogen, and other
essential nutrients
• Control of population of harmful invertebrate
species
• Direct production of certain foods
manufacture useful products such as silk
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Phylum Echinoderm
• Entirely marine group containing sea stars,
brittle stars, urchins, sand dollars, sea
cucumbers, sea lilies
• Marked radial symmetry
• Unique water vascular
system - tube feet
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Sea Urchin
Echinoderms
• Organ systems
• Echinoderms have bilateral symmetry as larvae
and radial symmetry as adults
• 3 germ layers
• No cephalization or Segmentation
• Coelum
• Sexual (some hermaphroditic; asexual by
regeneration)
6500 known species
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• Echinoderms and chordates are
deuterostomes
• At first glance, sea stars and other
echinoderms, phylum Echinodermata
– May seem to have little in common with
phylum Chordata, which includes the
vertebrates
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• Chordates and echinoderms share
characteristics of deuterostomes
– Radial cleavage
– Development of the coelom from the
archenteron
– Formation of the mouth at the end of the
embryo opposite the blastopore
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• Unique to echinoderms is a water vascular
system
– A network of hydraulic canals branching into
tube feet that function in locomotion, feeding,
and gas exchange
A short digestive tract runs from the
mouth on the bottom of the central
disk to the anus on top of the disk.
Central disk. The central
disk has a nerve ring and
nerve cords radiating from
the ring into the arms.
Digestive glands secrete
digestive juices and aid in
the absorption and storage
of nutrients.
Figure 33.39
Radial canal. The water vascular
system consists of a ring canal in the
central disk and five radial canals,
each running in a groove down the
entire length of an arm.
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Stomach
Anus
Spine
Gills
Ring
canal
Gonads
Radial
nerve
The surface of a sea star is
covered by spines that help
defend against predators, as
well as by small gills that
provide gas exchange.
Madreporite. Water can flow
in or out of the water vascular
system into the surrounding
water through the madreporite.
Ampulla
Podium
Tube
feet
Branching from each radial canal are hundreds of hollow, muscular tube
feet filled with fluid. Each tube foot consists of a bulb-like ampulla and
suckered podium (foot portion). When the ampulla squeezes, it forces
water into the podium and makes it expand. The podium then
contacts the substrate. When the muscles in the wall of the podium
contract, they force water back into the ampulla, making the podium
shorten and bend.
Sea Stars
• Sea stars, class Asteroidea
– Have multiple arms radiating from a central
disk
• The undersurfaces of the arms
– Bear tube feet, each of which can act like a
suction disk
Figure 33.40a
(a) A sea star (class Asteroidea)
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Brittle Stars
• Brittle stars have a distinct central disk
– And long, flexible arms
Figure 33.40b (b) A brittle star (class Ophiuroidea)
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Sea Cucumbers
• Feather stars
– Crawl about using their long, flexible arms
Figure 33.40d
(d) A feather star (class Crinoidea)
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Sea Daisies
• Sea daisies were discovered in 1986
– And only two species are known
Figure 33.40f
(f) A sea daisy (class Concentricycloidea)
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Phylum Chordata
• Includes animals with a “backbone”
• 7 Classes within the Subphylum
Vertebrata
Sharks, bony fish, lamprey,
amphibians, reptiles, birds, mammals
• We will talk about them in detail next
time……….
• http://quizlet.com/2981733/biologyflash-cards/
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