Bio 102 Exam 3

The Plant Cell

-Cell wall made of cellulose -Primary cell wall on outside -Secondary cell wall on inside -Vacuole- used for storage and osmotic regulations -Chloroplast * has all the organelles of an animal cell too

Gymnosperms have male and female cones

-Each scale on the female cone produces Megaspores -Each scale on the male cone produces microspores

Structure of Roots

-Epidermis -Cortex (ground tissue) -Stele (Vascular tissue) Pericycle- outermost cells of vascular bundle Endodermis= Innermost cells of cortex**

Vascular tissue arranged in a vascular bundle

-Fibers -Phloem -Xylem Vessels -Sieve tube -Companion cells

Move to land- locomotions

-Many fish have fins that are boney extensions -Some fossils and some fish today have flesh/muscle surround their fin bones -The muscled limbs of land animals are thought to have evolved from the simpler lobe-like muscled fins ex/ Mudskipper, lungfish -can walk on land for short periods

Seed Dormancy

-Many seeds are dry at maturity and this can allow the plant to withstand cold weather or other unfavorable conditions. When Dry seeds take up water-called imbibition Seeds that do not immediately germinate into plants-dormant -there are many adaptive mechanisms in various plants that allow them to regulate when to release the dormancy to fit their environment. Some seeds only germinate when their hard seed coat is damaged like alfalfa

Chordata: Mammalia

-Monophyletic class within the tetrapods Distinguishing characteristics: 1. Insulating hair or fur (keratin). 2. Endothermy—regulate body temperatures with internally generated heat. 3. Mammary glands for lactation - adaptation of sweat glands used to feed young

Insect Life Cycles

-Most arthropods of through distinct stages in their life cycle -The stages are distinct because of the exoskeleton -When they shed one exoskeleton they must rapidly grow before the next exoskeleton can be formed/finished

More complex animals develop symmetry

-Radial symmetry -Bilateral symmetry

The Pine Seed Structure

-Seed coat (Integuments) -Gametophyte -Embryo parts (Sporophyte II = 1n) -Cotyledones (embryonic leaves) -Shoot apical meristem -Hypocotyl -Root

The Ovule

-The megagametophyte develops inside the spore wall and the whole structure is called the Ovule -It stays within the Sporangium producing archegonia while still on the parent sporophyte (2n)

Pollen

-The microgametophyte develops while still inside the spore wall -This multicellular pollen is released and travels to land near the megagametophyte -The Pollen is light and has only a few cells so still can act like a spore and travel to the mega-gametophyte and egg Contains two haploid nucleii

How does the Xylem function even though its dead?

-When stomata open for gas exchange for photosynthesis (and respiration) the leaf loses lots of water. -Cell wall acts like a sponge, as they lose a little bit of water, it pulls the rest up through the Xylem by osmosis

Plant cells act as a group

-all move together -part of the reason there is less cancer in plants** Tissues- are composed of many cells unified for a common purpose

Traits of early metazoa

-body symmetry -neural nets -Gastrulation -Ectoderm -Endoderm -Mesoderm

Ray Finned Fishes

-came from early boned fish, they have true bones

Tetrapods: Amphibians

-earliest group of tetrapods -live in wet areas bc they breathe through their skin -strong pectoral muscles to help them move -external fertilization of eggs that need to live in aquatic environments

Giant squid and colossal squid

-have been reported in myths and in recent history. They can be very aggressive and have been seen attacking ships and in one case in a fight with a sperm whale. They can get to be 46 ft long (16 m)

What does an ovary do?

-helps control pollination -develops into fruit Functions: -protects seeds -disperses seeds

Move to land

-lungs are not modified gills, but extensions of the digestive tract -Many fish have swim bladders- it can change its buoyancy by squeezing or relaxing it

The Shoot Apical Meristem (SAM)

-originally formed in the embryo - A small population of 'stem' cells you need a microscope to see. - Creates the stem, leaves, and flowers

Working knowledge of osmosis

-solutes do not move across the membrane - instead the water moves to balance the concentration imbalance energy of osmosis= same energy of hydrogen gradients

Flowers

-stems modified for reproduction (like cones in gymnosperms -flowers differ by producing their ovules inside an extra vessel called the ovary/pistil Petals, stamen, sepals, receptical, pistil (ovary, style, stigma)

Transpiration

-when water is lost from leaf -water is absorbed by roots Transportation stream- water traveling through the plant

Fruit aids in seed dispersal

-wind -animals: seeds can be passed through them or on them

Chordate subphyla

1) Cephalochordates (sit in the ground and filter feed) 2) UROCHORDATES (look like jellyfish but still grouped with chordates bc the larva looks like adult of advanced species) 3) Vertebrates

3 main tissue types found in all plant organs

1) Epidermal tissue- elastic cuticle, how plants obtain water in the nuclei 2) Ground tissue- basic cells 3) Vascular tissues- Transports water- Xylem (big bubbles in cross section) and metabolites - Phloem ( collective little bubbles in cross section)

Land Plant Life Cycle

1) Sporangium produced on the sporophyte 2) Undergoes meiosis which creates either microspores or megaspores (1n) 3)Spores undergo mitosis, creates mega Gametophyte or Microgametophyte 4) Mega Gametangium (archegonium) produced on the mega gametophyte, Micro gametangium produced on microgametophyte (antheridium) 5) Houses either egg or sperm, goes through fertilization 6) Becomes zygote (2n) , undergoes mitosis 7) Becomes embryo, mitosis occurs and cycle repeats

Process of sugar transportation in the Phloem

1) Sugar is pumped into the companion cell and Sieve tube. 2) The osmotic pressure drops (hypertonic solution) and draws water into the phloem. 3) The phloem becomes pressurized and flows away from the source. 4) At the sink, sugars are pumped out of the companion cells and the water flows out of the phloem too. -Phloem goes wherever there is a companion cell thats letting sugars flow out Pushing= positive pressure

Why so many beetles?

1) They have been here a long time (some of the first to land) 2) Coevolved with plants - against plant toxins and -with plants as pollinators. 3) Can fly 4) Have tough exoskeleton 5) Resilient to environmental change -fast life cycle and many progeny

Angiosperms are the most abundant land plants (gymnosperms were even before them)

1) Variation in flower structure can promote out crossing (non self pollination) as well as create new barriers to reproduction - new species. 2) Leaves of angiosperms are more efficient at transporting water and so more efficient at photosynthesis

2 ways to get pollen

1) wind 2) pollinators

Micro Sporangium and Mega Sporangium

1n

Leaf Anatomy

A flattened organ primarily used in photosynthesis -Structured for light absorption and efficient gas exchange -Most are shorter lived than the rest of the plant and are discarded after a while. -The region of cells between veins in the blade is called the lamina- DOES THE BULK OF PHOTOSYNTHESIS

Phloem needs to maintain

A plasma membrane

The middle layer of a lichen contains

Algae

How to reproduce away from water

Amniotic egg- allow the embryo to develop and be protected in non-aqueous environments. The embryos are surrounded by three membranes/layers of fluid creating a 'little pool' allowing the embryo to develop on land. These structures are still called eggs even though is is past the point of fertilization A shell of calcium carbonate is found on the outside of the egg - this feature added by the vaginal wall requires that the egg be fertilized internally - another adaptation suited to living on land.

Parental Care

Any action by a parent that improves the ability of its offspring to survive. Among animals, mammals and birds provide the most extensive parental care. Female mammals lactate—they produce milk and use it to feed their offspring after birth. Among large animals, the evolution of extensive parental care is hypothesized to be a major reason for the evolutionary success of mammals and birds. In both lineages, mothers produce relatively small numbers of large, high-quality offspring.

10) When you eat cauliflower you are eating...

Apical Meristems

Adventitious Roots- originates from stems and/or leaves

Banyan tree - Adventitious roots allow the tree to spread over large areas Adventitious 'Prop' roots form from the stem of plants for support

Not all dinosaurs went extinct

Birds

Early boney fish- armored fish

Bones are collagen (protein) with a deposit of hydroxyapatite The first bones in the fossil record boney scales on the body and then plates surrounding the superior/ head end of the body called the Cranium(like a helmet) Next the internal vertebrae became boney

Modified stems

Cacti and succulent plants- water storage Bulb- Stem with fleshy leaves Rhizome- below ground horizontal stem (Ginger) Stolon- above ground stem (Strawberry)

535 Mya Early Animals as seen in the Cambrian fossils

Called the Cambrian explosion because they appeared quickly (in the fossil record) Fossils more likely since many animals have shells and bones Most major groups are represented in these fossils Present in these groups are bones, shells, segmented bodies, and more efficient predators

In between xylem and phloem...

Cambium

Root Crops

Carrots, Radishes, Turnips, beets, sweet potatoes -BUT NOT POTATOES

Hagfish and Lampreys

Chordates/vertebrates, but jawless, no true bones -Hagfish release a slime into the water when attacked Lampreys- live as a parasite

Tension Cohesion Theory-Water in the Xylem is...

Cohesive -it sticks to itself and so it acts like a 'rubber band' - a loss of water on the top pulls the water chain upward

Stem Anatomy- Cross Section

Different organs have characteristic patterns of vascular tissue. Two groups of Angiosperms are the Dicots and the monocots. -Functions to transport water and sugars up and down the plant as well as support leaves and reproductive organs

Whats different about dermal tissue in root?

Doesn't have a cuticle bc it has to absorb things

Multicellularity allows for higher levels of organization

Early stages in Metazoa multicellularity/development Multicellular organisms with specialized cells can develop groups of similar cells organized into tightly integrated and functional units called TISSUES - First level of organization Single layer of 'epithelium' covering multicellular body. -Most sponges only have this level of complexity

Protostomes- Annelida

Earthworms and Leeches Multicellular, bilaterally symmetric, CNS, Cephalization, three tissue types, protostome, coelom, segmented

Metazoan (animalia)

Eukaryotes -Heterotrophic (ingest prey) -Life cycle is diplontic (no multicellular haploid) -Store their carb reserves as glycogen -Multicellular (specialized cells) -No cell wall- instead have extracellular matrix -Almost all phyla contains neurons that transmit electrical signals to other cells and muscle cells to allow movement

Root Hairs

Extensions of individual epidermal cells (so small!) located near the tips of roots. Functions: -increase surface area -absorb water and minerals -Mosses have rhizoids (hairs) but no roots

Enchinodermata

Features; -Larvae have bilateral symmetry -Water vascular system allows some transport and hydrostatic pressure 1. Podia extend from arms 2. attach and move species (don't confuse with cillia which are cellular organelles) -The more common image we have of a sea urchin is just the endoskeleton The live organism looks different

Ophistokonts

Features; Single flagellum = unikonta Mitochondria have disc shaped crustae in mitochondria ( other lineages have tube shaped christae) last common ancestor for Eukaryotic and Heterotrophic -branches include colonial, cell walls, multicellular, tissues have neurons, radial and bilateral symmetry

Fibrous Root

Finely branched - cover a large surface area. More efficient absorption of water & minerals at surface -Roots hold the soil to prevent erosion. Example: Grass

The first animal/metazoa fossils

Fossilized sponge like creatures Found in a crevasse of a stromatolite 650 million year old -Fossilized worm tracts

What comes next in the listed life cycle sequence: Zygote, meiosis, haploid stage,

Gametes

Female reproductive structures- ovules are in the ovary

Gymnosperms- develop ovules in 'naked' on the upper surface of cone scales Angiosperms- develop ovules in the ovary of the pistil/carpel

Protostomes- Arthropoda

Huge phylum, Multicellular, bilaterally symmetric, CNS, Cephalization, segmented, three tissue types, Protostome, coelom -Exoskeleton that needs to be shed for growth

Eutheria

Humans are a part -Eutherians have internal fertilization and are viviparous -Mammalian young are much better developed at birth than are those of marsupials.

Pollination/Pollinators

Hummingbird- flowers small and tubular Beetle- flat strong flowers to support crawling insect Bat- Nectar produced in nighttime, flowers large to support bats ex/ wild bananas Flies- flowers low to ground with odor and color of rotting meat

Angiosperms have Double Fertilization

In each ovule there are two fertilization events. - One event produces the embryo that divides to become the new sporophyte (2N) - The other fertilization combines one sperm nucleus with two female gametophyte cells to becomes the endosperm (3N)

Simple and Compound Leaves

In simple leaves the blade lamina fills around all the veins. In compound leaves the blade lamina only extends around subsets of the veins creating leaflets Hint - leaves have axially buds above the base of the leaf on the stem, leaflets do not.

Innovations that occur in some vertebrates

Innovations that occur in some members of this group 1. Bony exoskeleton. 2. Jaws. 3. Bony endoskeleton. 4. Limbs capable of moving on land. 5. Amniotic egg.

Root Structures: Lateral Roots

Lateral roots-initiate growth from within the older root on the vascular tissue. They organize and then grow out through the ground tissue and epidermis.

Leaf Abscission

Leaves on a plant are consistently renewed. When a leaf is older, or less efficient, it is typically abscised (cut off the plant) in a controlled way. Plants that drop all their leaves seasonally are called Deciduous (fall leaves)

Gastrulation Significance

Mesoderm- allows formation of coelum (a tube within a tube) ; -cushions organs -seperations internal from external environment -allows formation of body organs

Angiosperm seed structure

Monocot- corn Dicot- bean -Seed Coat developed from maternal tissue surrounds and protects the embryo -An Endosperm (sometimes still present in mature seeds) a separate genetic composition (3N) to the embryo and usually serves to store energy for the embryo to use later -A new Embryo/sporophyte with root and shoot and some leaves already formed.

Angiosperm Leaf Vein Pattern

Monocot- parallel veins Dicot- netted veins

Chordata: Reptilia

Monophyletic group Reptiles are well-adapted for terrestrial life because of three distinguishing features: 1. Production of keratin (protein) for scales and claws. 2. Well-developed lungs. 3. Amniotic eggs.

Pollination as a mutualism

Most flowering plants pollen is transported by animals -- Pollen: high in protein - Also has lipids, minerals, starch - Flower can produce Nectar, Oils and Resins -plant gets pollen transferred, animals get reward ex/Bees and flowers are the classic example of a mutualistic relationship. The bees collect pollen as well as nectar provided by the flowers. In exchange some of the pollen is transferred from flower to flower

Four Subphyla of Arthropoda

Most number of species of any Animalia 1) Subphylum crustacea- crabs, crayfish, pilings, waterless, copepods 2) Subphylum Chelicerate (scorpions, ticks, spiders) 3) Subphylum Uriramia- Moths, beetles, butterflys, centipedes, grasshoppers, bees 4) Subphyla Trilobita- extinct

Multicellularity allows further organization

Multicellular animals develop through a series of stages. One of the early stages is Gastrulation -(Cnidaria and Ctenophora just have ectoderm and endoderm)

Protostomes- Platyhelminthes

Multicellular with bilateral symmetry and a CNS, -Protostome but does NOT make a coelom - Acoelomate - poor locomotion (also no segmentation) -Amazing regeneration abilities** - Flat body to absorb O2 and nutrients ( large surface area)

Cnidaria and Ctenophora

Multicellular with radial symmetry and neurons

Protostomes- Mollusca

Multicellular, bilateral symmetry, CNS, Cephalization, three tissue types, coelom, complex organ systems -either goes on to become a snail, squid, clam -Advanced locomotion: Squids have lost almost all of their shell and swim by jet propulsion

Porifera- Sponges

Multicellular, different cell types, but no organized cell layers or nervous system

The vertebrates distinguished by two synamorphies (542 mya)

No jaws 1. The cranium (skull) is a bony, cartilaginous, or fibrous case that encloses and protects the brain. 2. A column of cartilaginous or bony structures called vertebrae, which form a column along the dorsal sides of most species, protecting the spinal cord. Notochord becomes the Vertebrate

Embryophyte Phylogeny

Non- vascular plants- gametophyte dominant (bryophytes) Vascular plants- Sporophyte dominant (Tracheophytes) Seed plants appear (gymnosperms and angiosperms)

Gametophyte(1n) Reduction

Not only is the sporophyte (2n) dominant, but the extent of the gametophyte is reduced in tracheophytes and seed plants. ex/ The gametophytes in angiosperms are composed of only 3-8 cells comparted to the 10,000's of cells in a moss /bryophyte gametophyte. -They are essentially becoming more Diplontic***

C4 leaves- C4 photosynthesis

O2 can compete with CO2 as a substrate for RUBISCO making photosynthesis much less efficient. -Many plants have adaptations to increase the CO2 concentrations in photosynthesizing cells to allow more efficient photosynthesis. In C4 plants, CO2 is concentrated in the bundle sheath cells. Maize and crabgrass are C4 plants.

Tap root

One main root -Continuation of the primary root -Ideal for anchorage -Penetration for deep water -Storage area for food Example Carrot

Phloem transport happens through

Osmosis Isotonic solution- normal Hypotonic Solution- Diluted (swollen red blood cell) Hypertonic Solution- Concentrated (shrunken blood cell)

Ground Tissue- cell types

Parenchyma cells- make up bulk of organs, make up starch (potato cells etc) -thin cell wall, just primary Collenchyma cells- spongy unevenly thick cell wall layer in stems and leaves, celery fibers Sclerenchyma cells- thin primary cell wall then thick secondary hardened with hemicellulose and lignin(waterproof) -hard tissue, cells dead at maturity ex/ coconut shells, cherry pits

Epidermal Cell types

Pavement cells- thin cell wall on inner wall but often thick waxy layer (cuticle) on outer cell wall side Guard cells- guard the stomatal pore (allow gas in and out of plant) Trichomes- HAIRS provide protection from being eaten and provide shading

Chordata: Mammalia-Monotremata

Platypus and Echinida Most ancient group of mammals living today; found only in Australia. They lay eggs and have low metabolic rates. They have a leathery beak or bill; platypuses feed on small animals in streams and echidnas feed on ants, termites, and earthworms on land. Platypuses lay their eggs in a burrow, echidnas keep their eggs in a pouch on their belly.

The root cap functions to:

Protect the root apex

Why the seed?

Protection: The seed coat, derived from the integuments of the ovule, acts to protect the embryo. Dispersal: When the seed is eventually released from the parent plant, it may stay close to the parent, or be carried off by wind or animals. Dormancy: Within the seed coat, a seed may remain dormant for days, months, or even years until favorable conditions trigger germination.

Embryo Development: Protostome vs Deuterostome

Protostome- first mouth (becomes the anus) Deuterostome- second mouth -the split was a major evolutionary events

Primitive animals as seen in the Ediacaran fossils (part of the proterozoic-precambian)

Rare fossils since the animals are all soft and difficult to preserve -Most forms are not seen in the Cambrian (first era of paleozoic)

Which one of the following was needed to produce seeds?

Retain spores on sporophyte

When a plant is said to be an embryophyte that means it

Retains the young sporophyte on the gametophyte

Water and minerals enter the plant through the...

Root -Endodermal cells that surround the vascular tissue have a waxy Casparian strip that force water to move through cells into vascular tissue So water and minerals can only travel through the cytoplasm (SYMPLASTIC movement) Movement through the cell wall and intercellular space (APOPLASTIC movement)

Root Function

Root Functions: 1) Anchor the plant 2) Absorb water & minerals 3) Store food (starch) 4) Propagate or reproduce (some plants)

Lateral Cambium- meristem

Secondary growth- woody plants -Ring of Vascular tissue connects to make a layer -Produces new 'rings' (layers) of Xylem and Phloem each year

Fruit types

Simple- fruit that develops from a single matured ovary/pistil (tomato) Aggregate- Fruit that develops from many matured ovaries in one flower (raspberry) Multiple- fruit that develops from many flowers (pineapple)

Floral variation in Floral Structure allows specificity in pollination

Some flowers have Fused petals that form floral tube (nectar made at bottom) -Only long-tongued pollinators can reach the nectar at the bottom.

Mammals- Placenta

Some mammals are viviparous -the egg is retained in the mother and a biological connection develops that delivers nutrition to the embryo as it develops. (similar to a seed in plants) Advantages: 1. Offspring develop at a more constant, favorable temperature. 2. Offspring are protected. 3. Offspring are portable—mothers are not tied to a nest.

Phloem transport goes from source to sink

Source- sugars loaded into Phloem Sink- Sugars unloaded from Phloem -Phloem transport goes up and down the plant

Modified leaves

Spines, bracts, succulents (storing water), bulbs (store nutrients), scales (protection, good for winter)

Dispersal

Spores were the main way that plants spread over Earth for the first 75-100 million years of life on land. The first seed plants are seen at 400-375 million years ago All Land plants: The sporophyte develops on the Gametophyte Seed plants: The gametophyte is developed on the Sporophyte

The guard cells are found in the ____ and during a normal day are ___ to the surrounding cells.

Stomata, Hypertonic

Phloem- How are sugars transported in the plant?

Sugars flow from mature leaves to growing parts of the plant -Sugars flow from Seeds into growing seedling -Sugars flow from roots to stem in spring ex/ carrot plants

Root Architecture

Tap root vs Fibrous

Chordata: Mammalia- Marsupiala

The 275 known species of marsupials live in Australia and the Americas. Marsupial embryos have a placenta, but the young are born poorly developed after only a short embryonic period. -They continue to develop while attached to their mother's nipple, where they suck milk usually in a pouch on the abdomen of the mother. -They stay with their mother until they grow large enough to move independently.

A fundamental split within protostomes

The Lophotrochozoa- grow by extending the size of their bodies and skeletons. Includes the mollusks and the annelids. The Ecdysozoa- grow by shedding their external skeletons or outer coverings and expanding their bodies. Includes the arthropods and the nematodes.

Plant Apical Meristems

The basic plant body originates from Shoot and root apical meristems Growth from the apical meristems- primary growth. - Responsible for all growth in height/length of the plant.

Primary and Secondary Cell Wall

The cell wall is produced in layers from the inside out First primary and then Secondary on the inside of the primary wall, -primary wall is produced as the cell is growing and the secondary thickens the cell wall after it is done elongating

Fertilization

The egg is in the ovule and when the pollen delivers the sperm it makes an embryo. -A second fertilization event makes sterile tissue called endosperm that aids in nourishing the young embryo

Pine seeds

The parents sporophyte (2n) releases seeds that contain the next generation of sporophyte (2n) as an embryo -Two seeds are produced from each scale of the female cone

Turgor Pressure

The pressure of water in each cell that holds the plant up is called the

Gymnosperms- Cones

The reproductive structure of gymnosperms is the cone -The sporophyte produces many scales on a short stem -Cone scales are tough leaves modified for reproduction

The Root Apical Meristem

The root apical meristem is located at the tips of the growing roots The root apex is more organized than the shoot apical meristem.** Growth can be divided into zones with common activities RAM = "Zone of cell division" Zone of elongation Zone of differentiation

The Gymnosperm Seed (pine)

The seed is a structure containing layers of different life cycle stages. -allows the parental sporophyte to support/nourish the next generation of sporophyte. -after fertilization the seeds can take years to develop -When mature, the cone opens and releases the seeds -Pine 'nuts'= seeds

Eukaryotes- Supergroups

There are 4-7 major groups -Plants, animals, and fungi are all multicellular groups where the majority of the group lives a life on land Last Common Eukaryotic Ancestor (LECA)

Root cap

Thimble-shaped mass of cells at the tip of the root What does it do? Protects the root from mechanical injury (soil is abrasive!)

Cellular extensions of the plant epidermis that grow out, off of the shoot are called:

Trichomes

Primitive Animals- Porifera

Truly multi-cellular sessile organisms (differentiated cells) -Both have similar cells - Choan means collar- but Porifera has other cell types

Seed plants produce

Two types of spores- Heterospory Pollen and Ovules

Dicot stem

Vascular tissue becomes a ring in a dicot system

Another type of Deurostomes- Chordate

Vertebrates are part of a bigger group of phylum Chordata 4 features: 1. pharyngeal gill slits. 2. A dorsal hollow nerve cord that runs the length of the body, comprised of projections from neurons. 3. A supportive but flexible rod, called the notochord, that runs the length of the body. 4. A muscular post-anal tail.

Transpiration Stream

Water and minerals travel through the Xylem from the root to the shoot

11) Water moves through the vascular tissue from root to leaf powered by

Water evaporation at the leaf

Primates

We are primates/ hominidae Humans and Chimpanzee Share 98.5% DNA identical. Orangutans have about three times the differences ~95% identical. Humans have 23 chromosome pairs chimps have 24 chromosome pairs (18 pairs are virtually identical)

Wilting

When more water transpires than can be replaced the plant wilts - looses its shape from loss of water pressure

Tracheids occur in the ____ and are _________ at maturity.

Xylem, dead

How do the vascular tissues of plants work?

Xylem- brings water and nutrients up Phloem- Sugars where needed Absorption 'end' and photosynthetic 'end'

Scientifically speaking a Fruit is not just the part of the plant we eat with fleshy tissue. A fruit is defined as:

a matured ovary

A ovule after fertilization matures to become a:

a seed

In angiosperms pollen develops in the

anther- through meiosis then mitosis

First fossils on land

arthropod foot prints -a lobster sized centipede

Conifer Female- Ovulate cone

bears many scales- modified leaves. Each scale has two ovules (unfertilized seed), or MEGASPORANGIA, on its upper surface -Within each ovule, meiosis produces four haploid cells - three degenerate and one develops into a megaspore (1n) -The megaspore is not released but divides by mitosis to produce the megagametophyte right on the parental sporophyte. *** -Eventually produces archegonia

Which of the following have unevenly thickened primary walls that support young, growing parts of the plant?

collenchyma cells

Sieve tubes kept alive by

companion cells

Male Pine Cone

consists of modified leaves called scales that bear sporangia on the underside Microspores develop into immature male gametophytes (pollen grains) consisting of FOUR cells: two of which (a generative cell and a tube cell) are involved in reproduction

Which classifies as secondary growth?

development of wood and bark

Seed plants: the gametophyte

develops on the sporophyte

Pine trees

don't look like they're changing bc they don't shed their leaves but they're highly reproductive

What type of cell/tissue is triploid (3N)?

endosperm

Life cycles of animals

ex/ jellyfish Complexity is produced through many developmental steps Some stages of development can be long lived and some can be morphologically very different than other stages. Jellyfish can go through Larval (after zygote), Polyp, Ephyra and Medusa stages

Deuterostomes- Enchinodermata

ex/ sea urchins, sea stars - 5 part Radial symmetry - Ca CO3 endoskeleton - Water vascular system - PODIA extend from body to grip things -Multicellular, CNS, three tissue types, larvae have bilateral symmetry

Arthropod body plan

exoskeleton- protects body, supports organs, creates mechanical support -limits growth and gas exchange

Ovule in angiosperms

female gametophyte -integuments + egg sac (mega-sporophyte), 8 nucleii which eventually become only 2 in the center of the ovule -meiosis occurs

The ovule allows for

fertilization without being in water as well as control and protection for the egg and pollination

Pollen of Flowering Plants is actually a reduced :

gametophyte

Vertebrates Milestones

gills-filter feeding structures to gills for gas exchange -powers large organisms

In plants, which of the following are produced by meiosis?

haploid spores

Axillary buds

have dormant meristematic cells

30) Sieve tubes are ____________ relative to the parenchyma cells in the leaf.

hypertonic

Wind pollinated flowers

less showy, they don't need to attract pollinators -need to produce a lot of pollen (allergies) Insect Mimicry- There are many examples of pollination relationships. Some are not beneficial to the pollinator ex/ some flowers resemble a female wasp and male wasps are tricked into mating with the flower = allows pollen transfer

Most of the water taken up in a plant is

lost during transpiration

Formation of Jaws

opening and closing gill slits, cartilage eventually formed, then bones Vertebrates with jaws - skates and sharks (no true bones anywhere else)

Stoma

openings in Epidermis to allow gas exchange -found in high numbers in leaves but also in young stems -The guard cells (HYPERTONIC) open and close the stoma to allow gas exchange

A student examining leaf cross sections under a microscope finds many loosely packed cells with relatively thin cell walls. The cells have numerous chloroplasts. What type of cells are they?

parenchyma

Gastrulation

producing an internal digestive tract, or gut, and two layers of tissue the ectoderm (outside skin) and the endoderm (inside skin) -During Gastrulation a third layer of tissue can form filling in between the endoderm and the ectoderm. Body cavities created are known as the coelum

When the suction is released the water pressure

pulls back- NEGATIVE PRESSURE

Monocot stem

random vascular bundles

Fruit structure

related to the structure of the flower

Plant (sporophyte) basic body structure

root (primary and secondary) , then leaves, stems, flowers are shoot Node: composed of a leaf and an axillary bud

The plant root has to pull water from the

soil -Water coats surfaces of particles and fills small inter-particle spaces in the soil. -They break the surface tension of the water in the soil and also increases surface area for absorption of minerals and water

Seeds develop from

the fertilized ovules, fruit develops from the ovary -Plant organs and parts are named based on their developmental origin not function

After fertilization

the new Sporophyte begins

The seed

the pollen delivers a sperm to the Ovule and after fertilization the next generation of sporophyte develops inside becoming the seed

Phloem

thin cell walls, stay alive -Sieve tubes -Supported by companion cells -transport sugars

Most growth occurs at...

tips of roots and shoots- apical meristems (primary growth)

Xylem

tracheids and vessels (only flowering plants) -conduct water & minerals -thick cell walls, die at maturity

What is a neuron?

transmit electrical signals to other cells and muscle cells to allow movement -Some Cnidaria and Ctenophora have Neurons organized in a diffuse neural nets

After haploid nuclei mere to become a diploid nucleus then the cell

undergoes meiosis

Gymnosperms

vascular plants that produce seeds Gymno=naked Sperm=seed ex/ conifers, cycads, Ginkgo

We could have become bipedal because

we lived in grasslands, they absorb CO2 the best -we didn't need the protection from the trees, we ran bipedally

Carnivores plants

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Advantages of segmentation

you can drive innovation by reusing the same thing for different functions, help them to get bigger, similar to our spinal chord