deck_1403681 Flashcards Preview

Anatomy and Physiology > deck_1403681 > Flashcards

Flashcards in deck_1403681 Deck (286):
1

Types of plant tissue

1. Vascular tissue2. Ground tissue3. Dermal tissue

2

The plant body has a hierarchy of ___, ___, and ___.

Organs, tissues, cells

3

Components of the plant cell

1. Plasma membrane2. Cell wall - Primary cell wall - Secondary cell wall with lignin3. Plasmodesma(ta) - Channels that allow transport of food/hormones from cell to cell.

4

The three basic plant organs

1. Leaves2. Stems3. Roots

5

Two plant organ systems

1. Shoot system - Above ground2. Root system - Below ground

6

Plant cells store water in the ___ ___.

Central vacuole

7

Characteristic of secondary cell wall

Not permeable by water, causing cell death following maturation.

8

Root

- Anchors the vascular plant- Absorbs minerals and water- Often stores organic nutrients- May become photosynthetic + E.g., orchids

9

Root hairs

- Found in most plants- Occur at root tips where water/mineral absorption takes place- Increase surface area of root- Cannot absorb water if broken until they grow back

10

Modified roots

1. Prop roots - Develop above ground to create new shoots2. Storage roots - Store food and water3. Strangling aerial4. Buttress roots - Very large above ground5. Pneumatophores - Stick out of water to breathe

11

Two root systems

1. Fibrous roots - Monocotyledons2. Taproots - Dicotyledons

12

Stem

- Positions and supports leaf- May become modified to perform other functions

13

Anatomy of the stem

1. Apical/terminal bud - Located near the shoot tip and causes elongation of a young shoot.2. Axillary/lateral bud - Located at each node. - Meristems - Structure with the potential to form a lateral shoot, or branch.

14

Apical dominance

- Apical shoots inhibit growth of lateral buds.- Lateral shoots will grow if apical bud is removed.

15

Node

Place where leaf meets stem

16

Internode

Space between nodes

17

Meristem

Undifferentiated plant cell

18

Modified shoot examples

Runner, strawberry, rhizomes, iris, tubers, potato, bulb, onion

19

If left out too long, potatoes will sprout ___ ___.

Lateral buds

20

Corm

Contain a solid, underground stem. - E.g., garlic

21

Leaf

- Main photosynthetic organ of most vascular plants.- Cuticle and stomata

22

Stomata opening formed by ___ cells.

Gaurd

23

Trichomes are also known as ___ ___.

Leaf hairs

24

Petiole

Joins the leaf to a node on the stem.

25

Most monocots have ___ veins.

Parallel

26

Most dicots have ___ veins.

Branching

27

Leaf types

- Simple- Compound + Pinnate + Bipinnate

28

Simple leaf

One continuous blade

29

Pinnate leaf

Blade is broken down into leaflets

30

Modified leaves

1. Tendrils2. Spines3. Storage4. Bracts5. Reproductive

31

Modified leaves

1. Tendrils2. Spines3. Storage4. Bracts5. Reproductive

32

Three tissue of plant organs

1. Dermal tissue2. Vascular tissue3. Ground tissue

33

Dermal tissue system

- Consists of epidermis (in primary growth)- Covered in cuticle

34

Vascular tissue system

Carries out long distance transport of material between roots and shoots. - Consists of xylem tissue and phloem tissue.

35

Xylem tissue

Transports water and dissolved minerals upward from roots to shoots.- Dead at maturity.- Leave behind (yellow/red) lignin at death.- Two types of xylem cells + Tracheids + Vessel elements

36

Tracheids

- Long, narrow, tapered cells with pits on the cell walls.

37

Vessel elements

Short, wide cells with partially perforated walls.- Spiral-shaped

38

Phloem tissue

Transports organic nutrients (sugars) and hormones from where they are made to where they are needed.- Alive at maturity.- Sugars and hormones make up sap.Two types:- Sieve-tube members- Companion cells

39

Sieve-tube member

- No nucleus- Only have cytoplasm- Cannot undergo mitosis- Contain sieve plates at their ends- Run next to companion cells

40

Companion cell

Control metabolism in order to keep sieve-tube members alive.- Undergo mitotis- 1:1 ratio to sieve tube members- Run next to sieve tube members- Typically dyed blue

41

Phloem and xylem run ___ to one another.

Parallel

42

Ground tissue

Includes various cells that can be used for storage, photosynthesis, support, etc.- Three types + Parenchyma (most common) + Collenchyma + Sclerenchyma

43

Parenchyma cells

- Live at maturity with flexible primary cell wall- Metabolically active- Non-specialized and can divide to become other cells, but typically form xylem or phloem.- Common in vascular and ground tissue- Functions + Photosynthesis - Contain chloroplasts + Storage

44

Collenchyma cells

- Live at maturity with unevenly thickened cell wall- Common in ground tissues of stems and petioles- Also associated with phloem- Function + Flexible support which allows for plant growth

45

Sclerenchyma cells

- Dead at maturity with thickened cell wall containing lignin- Common in ground and vascular tissues- Cell types + Sclerids + Fibers - Long, tapered, non-digestible cells- Function + Support

46

Sclerids

Provide addition structure and support. - Variable shape

47

Fibers

Long, tapered cells that are non-digestible.

48

Tissue organization of leaves

- Epidermal barrier + Interrupted by stomata which allow for CO2 exchange.- Ground tissue + Sandwiched between upper and lower epidermis.- Vascular tissue + Continuous with vascular tissue of the stem.

49

Leaf structure (all leaves contain...)

- Upper and lower epidermis + Both contain cuticle with guard cells and stomata. + Epidermis does not contain chloroplasts and so it needs to be fed.- Mesophyll (composed of Parenchyma cells) + Monocots have one layer + Dicots contain palisade and spongy parenchyma- Vein

50

Vein

Vascular bundle containing xylem and phloem.

51

Meristems

Contain embryonic tissues that continuously generate cells for new organs. Work like stem cells.Types of meristems:- Shoot apical meristem + Elongate tips of shoots by primary growth.- Root apical meristem + Elongate tips of roots by primary growth.- Auxillary buds

52

Embryonic tissues leading to primary growth

- Protoderm- Ground tissue- Procambium

53

Protoderm

Gives rise to dermal tissue

54

Ground tissue

Gives rise to ground tissue

55

Procambium

Gives rise to vascular tissue

56

Primary growth

Growth in length of apical meristems at tips of roots and shoots.- Flexible- Eventually turns into secondary growth- Characteristic of all plants + Herbs only posses primary growth

57

Shoot apical meristems

Mass of dividing cells at the tip of the terminal bud.- Dome-shaped- Gives rise to the repetition of internodes and leaf-bearing nodes

58

Stem structure in primary growth

- Epidermis + One layer of cells and rarely more.- Cortex + Support tissues: - Collenchyma (live cells) - Sclerenchyma with fibers and sclerids (dead cells) - Parenchyma (live cells) + "Filler"- Vascular bundles + Xylem + Phloem + Procambium- Pith

59

Procambium

Undifferentiated cells that form xylem and phloem.

60

Pith

Composed of parenchyma cells - Compose the center of the stem in monocots and dicots. - Compose the center of the root in monocots only.

61

In gymnosperms and dicots, the vascular bundles are arranged in a ___ shape.

Ring- These rings separate the pith from the cortex.

62

Characteristics of monocot stems

- Vascular bundles scattered throughout the ground tissue.- Closed vascular bundle- No vascular cambium- No secondary growth + Due to vascular bundles being surrounded by sclerenchyma cells.

63

Root cap

Covers the root tip to protect the root apical meristem during primary growth. - Produce mucus to lubricate the root.

64

Root structure in primary growth

- Epidermis with root hairs- Cortex- Endodermis with Casparian strips- Stele + Vascular tissue- Movement of water and nutrients + Apoplastic pathway + Symplastic pathway

65

Cortex

Space between epidermis and endodermis composed of ground tissue.

66

Two types of plant epidermis

- Upper- Lower + Typically faces away from the sun

67

Annuals

Grow for one year and then die.

68

Biannuals

Grow for two years and then die.

69

Procambium

Gives rise to vascular tissue (primary) - Everything below is phloem - Everything above is xylem

70

Dicot roots have xylem in the shape of a ___.

Cross

71

Stele (a.k.a. vascular cylinder) composition

Center portion of the root.From outside in:- Endodermis + One cell thick- Pericycle + One or more cells thick- Sieve tubes in phloem- Trachieds and vessels in xylem

72

Pericyle

The only structure that gives rise to lateral roots that emerge from within. - Lateral roots are those that shoot off from the main root.

73

Secondary growth

Adds girth to stems and roots in woody plants.- Occurs in dicots but not in monocots- Occurs in stems and roots but not in leaves- Typically occurs after one year

74

Secondary plant body composition

Tissues produced by:- Vascular cambium- Cork cambiumVascular cambium and cork cambium are lateral meristems.

75

Apical meristems add ___ while lateral meristems add ___.

Length, growth

76

Vascular cambium

- Cylinder of meristematic cells- Phloem to outside, xylem to inside- One cell thick- Develops from original vascular cambium within the vascular bundles and some parenchyma cells within the cortex.- Mostly in stems and roots of dicots

77

Zone of division

Where mitosis occurs within the root.

78

Zone of elongation

Where root grow to potential size.

79

Zone of differentiation maturation

Where cells differentiate within the root to carry out particular functions.- Root hairs only occur at this zone.

80

Endodermis is ___ at maturity.

Alive

81

Root hairs

Act as capillaries to move water via capillary action.- Epidermal cells

82

Symplastic route

Water and minerals are moved through the cytoplasm from cell to cell from the root hair to the xylem.

83

Apoplastic route

Water and minerals do not travel through the cytoplasm of the cells until they reach the later cells. The cytoplasm is made to act as a filter, but the apoplastic route bypasses this to increase speed.

84

Secondary growth production

- Vascular cambium undergoes mitosis to produce xylem to the inside and phloem to the outside. + Xylem and phloem cells do not undergo mitosis.- Primary phloem is crushed as the secondary phloem expands.- Primary xylem is pushed into the pith by the secondary xylem until the pith is completely gone.- Secondary xylem continues to grow inwards, causing the stem to expand in width.

85

Determining age in plants

Xylem cells shrink with lack of water. This causes a small ring of xylem to form during the winter.

86

Cork cambium

Cylinder of meristematic cells.- One cell thick- Mostly in stems and roots of dicots- Develops from parenchyma cells in cortex- Forms cork to the outside until it ruptures the epidermis

87

Cork

- Contains lignin and suberin + Impenetrable by water or gasses- Dead at maturity- Contains lenticels

88

Lenticels

Breakages within the periderm which allow gases into the deeper layers of the plant tissue.

89

Periderm

Cork and cork cambium

90

Bark

Periderm and living (secondary) phloem

91

Sapwood

Conducting xylem

92

Heartwood

Non-conducting xylem

93

Wood

Secondary xylem- Consists of sapwood and heartwood- Forms annual rings

94

Girdling

Removal of ring of bark around the trunk of a tree to kill it. - Due to the removal of living phloem and so the roots do not receive food.

95

Gravitropism (gravity-positive)

Grow in the direction of gravity (down) - Characteristic of roots

96

Gravity-negative

Grow opposite the direction of gravity (up) - Characteristic of shoots

97

Statoliths

Starches that attach to root cells. Must be at the bottom of the root, so the root grows to ensure this placement. This is the cause of gravitropism in roots.

98

Grafting

Method of cutting and binding separate plants in order to form one hybrid plant.

99

Gas exchange mostly by these methods

- Stomata- Lenticles- Spaces between cells

100

Methods of fluid movement within xylem

- Adhesion- Cohesion- Evaporation- OsmosisPossibly due to capillary action, root pressure, or transpiration pull. Unidirectional from roots to tips.

101

Cohesion

Attraction between water molecules due to slight positive/negative charge.

102

Adhesion

Attraction between water molecules and the xylem walls.

103

Transpiration pull

Ultimately due to water rising upwards as a result of evaporation.

104

Guard cell

Open and close stomata. - Two per stomata, one on each side. - Contain chloroplasts.

105

Method of fluid movement within phloem

Fluids move by mass flow and is multidirectional.- Source vs. sink

106

Source vs. sink

Source may be a leaf, root, flower, etc. Active transport causes solutes to move to sieve-tubes. Water moves in to increase pressure, and bulk flow pushes solutes towards sink. Pressure and solute concentration decrease between source and sink, but solutes eventually reach the sink, lowering their water potential. Water enters the sink after the solutes.

107

Epidermis

- Undifferentiated cells.- Includes guard cells and other specialized cells- Present in primary growth but eliminated by secondary growth.

108

Kingdom Animalia

"Metazoa"- Eukaryotic- Multicellular- Heterotrophic- Lack cell walls- Only kingdom possessing nervous and muscle tissue.- Major groups: + Invertebrates + Vertebrates

109

Advantages of multicellularity

- Large size- Mobility- Stable internal environment- Relative independence from environment

110

Origin of Animalia

Derived from the "colonial choanoflagelate," a prostist.- Monophletic

111

Evolution of Animalia

- Colonial protist is an aggregate of identical cells.- Forms to become a hollow sphere of unspecialized cell.- Cell specialization begins, and some cells become somatic cells while others become reproductive cells. + Somatic cells form the body.- Infolding + Hollow sphere of cells folds inward on one end.- Gastrula-like "protoanimal" is formed. + Cavity caused by infolding becomes the digestive cavity.

112

Eumetazoa possess ___ unlike Parazoa.

True tissues

113

Animal embryology

- Cleavage + Radial - Always indeterminate + Spiral - Always determinate- Cell fate + Indeterminate + Determinate

114

Cleavage

Series of rapid cell division by mitosis and cytokinesis.

115

Radial cleavage

- Occurs in deuterostomes- Indeterminate- 8 cell stage composed of symmetrical stacking of cells of the same size.

116

Spiral cleavage

- Occurs in protostomes- Determinate- 8 cell stage composed of smaller cells sitting on top of larger cells at an angle.

117

Developmental stages of Animalia

- Zygote undergoes cleavage until it becomes a morula.- Morula undergoes blastulation to become a blastula.- Blastula undergoes gastrulation to become a gastrula.

118

Morula

- Solid ball- Contains 64-100 cells- Undergoes blastulation

119

Blastulation

Cells of the morula move to the outside to increase the size of the ball, creating a blastula with a blastocoel.

120

Blastula

Hollow ball of cells.

121

Blastocoel

Hollow cavity within blastula.

122

Gastrulation

Process in which the invagination of the blastula creates the gastrula.

123

Gastrula

- Possess a blastopore- Possess germ layers + Ectoderm + Endoderm + Mesoderm - Blastocoel is contained between ectoderm and endoderm and thus reduced.

124

Blastopore

Opening to the primitive digestive system, eventually developing into a mouth or anus.

125

Coelom

Cavities that do not open to the exterior of the body.- Lining of coelom holds organs in place.- Surrounds heart, digestive, and respiratory structures in humans.Two types of formation:- Schizocoely- Enterocoely

126

Schizocoely

Solid masses of mesoderm split to form coelom.

127

Enterocoely

Mesoderm outpockets to form coelom.

128

Animal classification by four main attributes of body parts

1. Tissues2. Symmetry3. Body cavities4. Fate of the blastopore

129

Parazoa

- Lack true tissues- Typically asymmetricalTwo phylums only:- Placozoa- Porifera

130

Eumetazoa

- Possess true tissues

131

Radiata

- Radial symmetry- Diploblastic + Endoderm and ectoderm

132

Bilateria

- Bilateral symmetry- Triploblastic + Endoderm, ectoderm, and mesoderm

133

Germ layers present in the gastrula develop into ___ ___ ___.

Adult body parts

134

Body cavity variation

- Acoelomate + No cavity- Pseudocoelomate + Cavity touches endoderm and mesoderm- Coelomate + Cavity touches medoderm

135

Protostome

- Mouth develops from blastopore.- Spiral, determinate cleavage.- Schizocoely- Mesoderm derived from cells on lip of blastopore.

136

Deuterostome

- Anus develops from blastopore.- Radial, indeterminate cleavage.- Enterocoely- Mesoderm derives from walls of developing gut.- All are coelomates.

137

Cambrian Explosion

Rapid appearance of most major animal phyla around 500 million years ago.

138

Parazoans

Means "poorly defined tissues."Includes:- Phylum Placozoa- Phylum Porifera

139

Phylum Placozoa

The most primitive metazoans.- Feed by absorption.- Marine, discovered by chance.

140

Phylum Porifera

- Sessile- Filter water through canal system- Mostly marine- Possess an inner, middle, and outer layer.Classes:- Hexactinellida- Calcarea- Desmospongidae- Sclerospongiae

141

Spongocoel

Large cavity in center of sponge. Water enters this cavity via the pores.

142

Osculum

Opening on top of sponge through which water exits.

143

Sponge body layers

- Outer + Pinacocytes + Porocytes + Myocytes- Middle (Mesohy/mesogleal) + Spicules + Spongin + Amoebocytes- Inner + Choanocytes

144

Pinacocytes (outer)

Flat epidermal cells

145

Porocytes (outer)

Create the pore.

146

Myocytes (outer)

Allow the osculum to contract.

147

Mesohyl/mesoglea (middle)

Gelatinous substance that contains the amoebocytes.

148

Spicules (middle)

Used for support with a hard texture.

149

Spongin (middle)

Used for support with a spongy texture.

150

Amoebocytes (middle)

Undifferentiated cells that form spicules and secrete spongin.- Form egg cells.- Receive food from coanocytes and pass throughout the sponge.

151

Choanocytes (inner)

Flagellated cells that move water throughout the sponge.- Modified coanocytes form sperm cells.- Feed by trapping food particles in their collars and passing it to the amoebocytes. Amoebocytes then send food through the rest of the body.

152

Three body plans of sponges

- Asconoid- Syconoid- LeuconoidMore complex body plans allow for more surface area for food absorption.

153

Asconoid

Simplest body plan. Consists of a tube.

154

Syconoid

Tube with wavy extensions on its sides.

155

Leuconoid

Most complex body plan. Matrix of canals with multiple osculums.

156

Gemmules

Characteristic of freshwater (and some marine) sponges. Trap the amoebocytes in the absence of water so that they can survive while the rest of the cells perish.- Result by asexual reproduction and hostile environments.

157

Amphiblastula

Larval stage of sponges.- Will not feed until they settle, which takes 2-3 days.

158

Asexual reproduction in sponges

- Budding- Regeneration

159

Sexual reproduction in sponges

- May be dioecious or monoecious- Sperm cells (modified coanocyte) enters another sponge and is engulfed by its coanocyte.- This coanocyte penetrates the egg cell, passing the nuclei of the sperm cell to create an embryo.- Embryo develops into an amphiblastula.- Larva settles and attaches to bottom or other surface.

160

Class Hexactinellida

"Glass sponges"- Contained 6 rayed spicules made of silica (glass)- Simple syconoids- Marine- Exist below 200 meters- Shrimp may become trapped inside- E.g., venus basket

161

Class Calcarea

"Calcareous sponges"- Spicules made of calcium carbonate- May be asconoid, syconoid, or leuconoid- Marine- Exist below 100 meters

162

Class Desmospongidae

- Comprises 80-90% of sponge species- Siliceous spicules and/or spongin- Mostly marine + Contains the only freshwater sponge families- Variable form- Leuconoids

163

Class Sclerospongiae

- Found in tunnels in coral reefs + May damage reefs- Variable form- May contain silica and calcium carbonate spicules- Leuconoids- One group is predatory

164

Colors of sponges usually due to ___.

Dinoflagellates

165

Mutualistic symbiosis in sponges

- Dinoflagellates + Zooxanthellae that perform photosynthesis for the sponge.

166

Boring sponges

Bore holes into the host for shelter, killing it.Affect:- Hermit crab shells- Corals- Mussels and other mollusks

167

Phylum Cnidaria

- Radiata- Possess mouth with tentacles- Blind gut + Mouth and anus are the same opening- Mesoglea gives them shape- Possess cynocytes- Diploblastic with organs- No respiratory system + Breathe by diffusion of gases through moist skin.- Excrete cellular waste via diffusion into the water.Classes:- Hydrozoa- Scyphozoa- Anthozoa

168

Morphology of Cnidarians

- Polyp + E.g., anemones- Medusa + E.g., jellyfish

169

Cnidae

Contain a coiled thread that is discharged when triggered.

170

Cnidae varieties

- Nematocyst + Inject venom for feeding and protection- Spirocyst + Sticky thread for entangling prey- Ptychocyst + Create tubes for tube anemones

171

Cnidocyte

Structure containing the cnidae.

172

Nerve net

Interconnected neurons lacking a brain or cephalization.- Achieves little integration of information but serves simple behaviors.- Characteristic of Cnidarias, Ctenophors, and Echinoderms.

173

Cnidarian body plan

- Outer epithelium (epidermis)- Mesoglea (matrix)- Inner epithelium (gastrodermis)

174

Class Hydrozoa

- Mudusoid or polypoid + Polyp form is dominant + Alternate between medusa and polyp form- Polymorphic- Acellular mesoglea- Cnidae in epidermis- Nerve net- External fertilization- May produce male and female medusas but at different times- Possess planula- Asexual or sexual reproduction- E.g., Hydra (genus), Obelia (genus), man-o'-war

175

Hydromedusae

Medusa stage of hydrozoans that have both polyp and medusa stages. - Very small and found in some corals

176

Polymorphism

Division of labor amongst the colonial polyps.- Gastrozoid: Ingest food- Gonozoid: Reproductive- Dactylozoid: Protective- Skeletozoid: Support

177

Genus Hydra

- Freshwater- Atypical + Single polyp- Polyp stage only- Asexual reproduction by budding- Not colonial

178

Portuguese man-o'-war

Genus Physallia- Colony of specialized polyps attached to tentacles, which are attached to a floating structure or sail (gas-filled medusa).

179

Planula

Ciliated larval stage of hydrozoans.

180

Life cycle of Obelia

Asexual via budding.Sexual:- Colony forms some reproductive polyps, called medusa buds.- Medusa, possessing gonads, is released.- Medusa undergoes meiosis to release sperm or egg into the water.- Sperm or egg come into contact with another gamete to create a zygote.- Zygote undergoes cleavage to form a planula.- Ciliated planula attached to surface and becomes a developing polyp.- Polyp reaches maturity and is able to reproduce asexually to create more polyps.

181

Class Scyphomedusae

- Medusoid or polypoid + Medusa stage is dominant + Alternate between medusa and polyp form- Most common cnidarians- Cellular mesoglea- Cnidae in epidermis and gastrodermis- Gonads in gastrovascular cavity- E.g., jellyfish

182

Scyphomedusae

Medusa form of Scyphozoa

183

Order Cubomedusae

Box jellyfish or sea wasp- Common in Australia- Venom paralyzes heart, muscles, and causes neurological damage in minutes.- Very small- Tentacles on 4 corners of bell

184

Genus Cassiopeia

Upside-down jellyfish- Common in mangroves- Mutualistic symbiosis with green algae that live within its tissues (oral arms)

185

Scyphozoa life cycle

- Scyphistoma undergoes strobilation to produce ephyra.- Ephyra matures into an adult medusa able to produce egg or sperm.- Following fertilization, ciliated planula develops and attaches to a surface to form a young polyp.- Polyp develops into a scyphistoma.

186

Scyphistoma

Mature Scyphozoa polyp able to undergo strobilation to produce ephyrae.

187

Strobilation

Process by which the scyphistoma produces ephyrae.

188

Ephyra

Young medusa stage of Scyphozoa that develops into an adult medusa.

189

Class Anthozoa

- Polypoid only- Cellular mesoglea- Cnidae in epidermis and gastrodermis- Contain septa (mesenteries) in gut- Skeleton of water- Capable of fission- E.g., corals and sea anemones

190

Septa (mesenteries)

Radial partitions within the body cavity.

191

Fission

Splitting in two will create two separate organisms.

192

Life cycle of Anthozoa

Asexual:- Budding- Fission (longitudinal/transverse)Sexual:- Sperm and eggs released by colony into water.- Zygote develops following fertilization.- Planula for about 4 days.- Planula settles and polyp begins to develop.- Polyp undergoes budding to create a colony. + Colony takes 4-5 years to sexually mature.

193

Following budding, polyps remain ___ to one another.

Connected

194

Black band disease

Bacterial disease that kills coral.

195

Coral reefs are nutrient-___.

Poor

196

Corals have a symbiotic association with ___.

Algae - Zooxanthellae (particularly dinoflagellates)

197

Hermatypic corals

"Coral forming" or "hard corals"- Stony, reef-building corals.- Possess zooxanthellae- E.g., Scleractinians and Hexacorallia

198

Coral reefs susceptible to deterioration by ___ and ___.

Fungus, bacteria

199

Ahermatypic corals

"Soft corals"- Octocorals and gorgonians- E.g., sea whip, sea fan, sea pen

200

Phylum Ctenophora

"Comb jellies"- Medusa-like- Diploblastic- No nematocysts (usually)- 8 comb rows with retractable tentacles (usually) and fused cilia + Largest animal to use cilia for locomotion - Considered plankton- Colloblasts- BioluminescentTwo classes:- Tentaculata + Two tentacles- Nuda + No retractable tentacles

201

Colloblasts

Sticky filaments that cover the tentacles and trap prey.

202

Characteristics of Eumetazoans with bilateral symmetry (applies to all phyla following this card)

- Cephalization + Nervous tissue is concentrated towards one end of the organism, producing a head region.- Triploblastic (3 germ layers) + Ectoderm + Mesoderm + Endoderm- Dorsal/ventral- Anterior/posterior

203

Three body forms found in bilateral organisms

- Acoelomate- Pseudocoelomate- Coelomate

204

Radiata are ___ while bilateria are ___.

Diploblastic, triploblastic

205

Phylum Platyhelminthes

"Flatworms" or planarians- Acoelomate- Gas exchange occurs through body surface- Hermaphroditic- Able to regenerate- Dorso-ventrally flattened to increase surface area- Incomplete digestive system + No anus- No respiratory system + Breathe by diffusion of gases through moist skin.- Possess protonephridia- Possess eye spotsClasses:- Turbellaria- Trematoda- Cestoda

206

Anatomy of a planarian

- Simplified cephalization with ganglia.- Eye spots to perceive light.- Pharynx connected to mouth at the center of the body.- Genital pore that leads to both male and female reproductive organs.

207

Protonephridia

"Flame cells"Hollow cell containing cilia and used for cellular waste excretion. Cilia draws waste products in through a tube and filters it out through the membrane folds. Other cells are unable to enter the flame cell.

208

Asexual reproduction in planarians

- Fission + Each piece when cut regenerates into a new animal. Anterior or posterior will form depending on which end is cut. Cutting a certain portion too close to the head or tail may result in two heads or two tails. Splitting the head forms two heads.- Regeneration + Process of growing lost body parts.

209

Sexual reproduction in flatworms

- Mostly hermaphroditic- Hypodermic impregnation + Penis acts as a dagger to penetrate the skin of another worm and deposit sperm.

210

Class Turbellaria

- Free-living + Not parasitic- Mostly small- Mostly marine- Possess Rhabdites + Cells unique to this class

211

Class Trematoda

"Flukes"- Parasitic- Syncitium + No separation between cells- Possess suckers- E.g., Schistosoma mansoni, liver fluke

212

Schistosoma (blood fluke) life cycle

- Mature flukes reside in blood vessels of human intestine.- Mating occurs in human and fertilized eggs are released in feces.- Eggs develop into "miracidium", which then infect snails.- Miracidium reproduce asexually, resulting in "cercaria."- Cercaria penetrate the skin of a new human host and develop into mature flukes.

213

Miracidium

Ciliated fluke larvae that prey on snails. - Cannot penetrate humans.

214

Cercaria

Fork-tailed fluke larvae that prey on humans.

215

Flukes cause ___ ___ in humans.

Liver damage

216

Class Cestoda

"Tapeworms"- Parasites- Lack digestive tract- Possess reproductive system- Possess excretory system- Possess a scolex- Possess proglottids- Hermaphroditic and able to self-fertilize- Usually only one individual + This is the reason for self-fertilization- May cause cysticerosis- E.g., fish, pork, and beef tapeworms + All can infect humans

217

Scolex

Head of the tapeworm. Adheres to the intestinal walls by the use of suckers.

218

Proglottids

Segments of the tapeworm body that contain the reproductive organs.

219

Cestoda life cycle

- Mature tapeworm lives in human intestine.- Self-fertilizes to create mature proglottids with zygotes.- Proglottids released in feces and then burst, releasing zygotes onto the grass.- Cow ingests the grass with zygotes.- Zygotes develop into larvae and travel from digestive system to bloodstream and then to the muscle, where they encyst.- Human eats poorly cooked beef and ingests larvae.

220

Cysticercosis

Condition in which a human ingests a tapeworm zygote by eating vegetables. The larvae encyst anywhere they are able to.

221

Adaptations for parasitism

- Adhesive organs- Sense organs reduced- Digestive tract reduced or lost- Body wall protection- Larval stages in different animals allow for utilization of different habitats.

222

Phylum Nemertea

"Ribbon worms"- Pseudocoelomates- Possess a proboscis with stylet- Posses a "rhynchocoel"- Complete digestive tract + Posses mouth and anus- First to develop a closed circulatory system

223

Proboscis

Mouth that is able to shoot out to catch prey.

224

Stylet

Spear at the end of the proboscis.

225

Rhynchocoel

Cavity above the digestive system. It only has one entrance and contains the proboscis.

226

Closed circulatory system

Blood is contained within the blood vessels.

227

Nemertea reproduction

Sexual:- SpawningAsexual:- Fragmentation

228

Fragmentation

If broken into multiple pieces, each piece becomes a new organism.

229

Phylum Rotifera

- Dioecious- Pseudocoelomates- Complete digestive tract- Multicellular- Microscopic- "Crown of cilia"- "Eutely"- Reproduce via "parthogenesis"- Possess a "peduncle"- Posses a bladder + Excretory organ

230

Eutely

Born with the same number of cells that they'll have throughout their entire life.

231

Crown of cilia

Crown is covered in cilia which are used to bring in food for filter feeding.

232

Parthogenesis

Asexual reproduction via the development of the unfertilized egg of the female.

233

Peduncle

Structure that is used to attach to substrate. Able to retract when animal is motile.

234

Phylum Nematoda

"Roundworms"- Free-living and parasitic forms + Mostly parasitic - Affect flora and fauna- Dioeceous- Very abundant- Unsegmented- Vermiform + Cylindrical in shape- Complete digestive system- Small brain with lateral, ventral, and dorsal nerve cords- Use a specialized gland for their unique excretory system- Sexual reproduction- Longitudinal muscles from anterior to posterior + Allow for longitudinal whipping- Possess a cloaca

235

Cloaca

Common opening for reproductive, digestive, and excretory system.

236

Free-living nematode species

Caenorhabditis elegans - Important decomposers

237

Simplest, non-damaging nematode species

- Pinworms- WhipwormsThese stay within the intestines and do not migrate to other tissues.

238

Roundworm (Genus Ascaris) life cycle in humans

- Ingestion of water/vegetables contaminated by feces with roundworm eggs.- Eggs hatch and larvae migrate to intestine.- Larvae burrow through intestinal wall into the bloodstream of lymph ducts.- Larvae migrate to heart.- Larvae migrate to lungs.- Larvae are coughed out, swallowed, and return back to the intestine where they mature.- Mature roundworm sexually reproduces to create eggs, released in feces.

239

Roundworms ___ before leaving each new tissue.

Molt (4 times total)

240

Hookworms method of infection in humans

Penetrate the skin, not contracted via ingestion. - Intestinal parasites that, like roundworms, migrate to other tissues.

241

Filaria

Nematodes that are microscopic until adulthood. Larvae within flies or mosquitoes are passed to the host where they mature. As they increase in size, they clog lymph ducts, trapping water in the tissues and causing swelling.Diseases caused by Filaria:- Elephantiasis- Larva migrans- Blindness

242

Larva migrans

Caused by dog feces, often on the beach. Larvae enter via the skin and later emerge through the skin to release eggs. - May be pulled out with a pencil a little bit at a time, but breaking the worm will cause infection.

243

Trichinella spirallis

Larvae reside in pork muscle which is ingested. They then form calcified cysts in the human muscle.

244

Phylum Mollusca

- Schizocoely (like all protostomes)- Coelomate (like all protostomes)- Abundant aquatic and terrestrial forms- Sexual reproduction- Excretory system + Metanephridia (type of nephridium)- Open circulatory system + Except in Cephalopods- 2nd largest animal group- Shell (usually present) composed of periostracum, prismatic layer, and nacreous layer.- Head and muscular foot- Radula + Except in bivalvesClasses:- Monoplacophora- Polyplacophora- Gastropoda- Bivalvia- Scaphopoda- Cephalopoda

245

Metanephridia (type of nephridium)

Excretory gland that acts as a kidney. Consists of a series of tubes with open ends to filter fluid within the coelom.- Reabsorbs usable nutrients prior to the release of waste.- Mollusks possess 2.- Connects coelomic cavity to the pallial groove.

246

Visceral mass

Gills and gut. Contains the internal organs and often protected by the shell.

247

Mantle

Layer of living cells that secrete the shell.

248

The shell is composed of ___ ___ and ___.

Calcium carbonate, proteins

249

Radula

Mouth that is able to protrude and retract.- Full of teeth- Made of chitin

250

Mantle cavity

Contains the opening to the digestive, excretory, and reproductive systems.- Anus- Nephridium- Gills- Reproductive organs

251

Hemolynth

Blood in mollusks.

252

Nephridiapore

Opening of the excretory system to the outside world.

253

Reproduction in mollusks

Egg or sperm develop in gonads and released into the coelom. Nephridia extracts them from the coelom and releases them into the mantle cavity so external fertilization can occur.

254

Shell composition

- Periostracum + External layer- Prismatic layer + Between periostracum and nacreous layer- Nacreous layer + Between prismatic layer and mantle

255

Pearl

Form when sand or a parasite is inserted into space between nacreous layer and mantle. Mantle secretes nacreous layer around the foreign object, creating a pearl.

256

Trochophore

Larva stage of chitons and gastropods.

257

Veliger

Larva stage of gastropods that contains a shell.- Develops from trochophore- No veliger stage in chitons

258

Class Monoplacophora

- Single conical shell- Uncommon- Mantle cavity located in space between foot and shell, surrounding entire foot.

259

Class Polyplacophora

"Chitons"- Means "many shells"- Suction to rocks to trap water in mantle cavity when the tide goes down. This allows the gills access to water.- Mantle cavity surrounds entire foot.

260

Class Gastropoda

- Variable shell types- Twisted shell in species with shells + In these species, mantle cavity and anus located at anterior + Undergo "torsion"- 80% of all mollusk species- Aquatic species possess gills- Terrestrial species use diffusion of oxygen to exchange gas through mantle cavity and mantle wall.

261

Torsion

The rotation of the visceral mass, mantle, and shell 180˚ with respect to the head and foot of the gastropod.

262

Shell types of gastropods

- Planospiral + Shell is flattened on both sides and coiled.- Heliospiral + Contain a helix and a spiral - E.g., conch- Shell-less + Mantle cavity at posterior - E.g., nudibranch

263

Mantle cavity is located at the ___ during the larval stage.

Posterior

264

Terrestrial gastropods use ___ fertilization.

Internal

265

Marine gastropods use ___ fertilization.

External

266

Class Bivalvia

- Dioeceous- Lack a radula- Complete digestive system- Siphons located in mantle cavity + Incurrent + Excurrent- "Umbo"- "Hinge ligament"- "Abductor muscles"- "Protractor/retractor muscles"

267

Umbo

Raised bump at anterior of bivalve.

268

Hinge ligament

Opens shell slowly.

269

Abductor muscles

Close shell quickly.

270

Protractor muscles

Push foot out.

271

Retractor muscles

Bring foot in.

272

Eye spots

Characteristic of scallops able to detect light.

273

Shipworms

Bivalve that lacks a significant shell and burrows in wood.

274

Glochidia

Bivalve that attracts fish with a lure resembling another fish. Releases its parasitic larvae which then attach to the gills of the fish to draw blood.

275

Bivalve feeding mechanism

Filter feeders. Mucus on gills moves food particles to mouth, and waste is excreted via the anus near the excurrent siphon.

276

Class Scaphopoda

"Tusk shells"- Single, tusk-shaped shell- Burrowing

277

Class Cephalopoda

- Walk on their heads ("foot-head")- Shell absent, reduced, or spiraled- Tentacles/arms with suckers- Single siphon + Able to close and trap water- Closed circulatory system- Well developed eyes/eyesight- Intelligent- Beak- "Pen"- Ink gland- Chromatophores- E.g., cuttlefish, squid, nautilus, octopus

278

Pen

Modified, reduced shell.

279

The tube of the squid is the ___.

Mantle

280

Mating in squids

Male uses his tentacle to retrieve sperm and injects it into the female in the form of a sperm sac. Male then makes a quick getaway.

281

Chromatophores

Cells that contain pigment and are able to contract or expand in order to change the color of the organism. Surrounded by muscle that controls contractions.

282

Nautilus

- Oldest cephalopods- Only live in last shell chamber- Possess a chambered shell with siphuncle.

283

Siphuncle

Tube that passes through the shell of nautiluses regulate gas flow and control buoyancy.

284

Octopi have no ___ body parts.

Hard

285

Ordovician seas

During this time there was an abundance of crinoids, nautiloids, and trilobites.

286

Lophophorates (may not be on exam)

- Posses lophophores + Mouth surrounded by ciliated tentacles- Protostomes and deuterostomes- Variable coelom formation- Variable fate of the blastopore- Ribosomes are protostome-likePhylums:- Phoronida- Bryozoa- Brachiopoda