BIO 193 - Exam I

prokaryotes

• cell membrane

• cytoplasm

• ribosomes

• DNA

• ex. bateria and archaea

eukaryotes

• nucleus

• membrane-bond organelles

• cytoplasm + ribosomes

• ex. animals, plants, fungi, and protists

protozoa

unicellular eukaryotes

metazoa

multicellular eukaryotes

multicellular requirements

• exchange (oxygen + nutrients)

• transport (movement)

• disposal (waste)

• division of labor (different jobs)

• communication (coordination with others)

charophytes

• ancestor; green algae that are closely related to land plants

• structure of the cellular membrane (circular formation)

• flagellated sperm structure

• being able to survive extreme environmental stress

autotroph

an organism that makes its own food (ex. algae)

heterotroph

an organism that relies on other sources for food (ex. animals)

four key derived land plant traits

1. alternation of generations

2. sporangia

3. gametangia

4. meristematic tissue

alternation of generations

reproduction; haploid gametophyte (n) → mitosis → gametes (n) → fertilization → diploid zygote → mitosis + growth → diploid sporophyte (2n)→ meiosis → spores (n) → mitosis → haploid gametophyte (n)

sporangia

spore protection; multicellular organs produce and protect spores

gametangia

gamete protection; multicellular organs produce and protect gametes

archegonium

gametangia; produces and protect the egg

antheridium

gametangia; produces and protect the sperm

meristematic tissue

growth; pool of undifferentiated cells capable of cell division

haploid (n)

a cell with one set of chromosomes; produced by meiosis

diploid (2n)

a cell with two sets of chromosomes; can undergo mitosis

gymnosperms

vascular plants with naked seeds (not enclosed in an ovary)

angiosperms

vascular plants with seeds enclosed in an ovary

brophyte

nonvascular plants that reproduce with spores

vascular vs nonvascular

transportation of nutrients

spores vs seeds

reproduction

xylem

veins that help transport water and minerals in a plant

phloem

veins that help transport sugars in a plant

moss

• nonvascular, seedless plants that reproduce with spores

• gametophyte (n) is the dominant generation

fern

• vascular, seedless plants that reproduce with spores

• sporophyte (2n) is the dominant generation

plant fertilization

pollen (contains male gamete) → pollinator → stigma → pollen tube → ovule → egg (female gamete) → fertilization → zygote → embryo → seed

sporophyte

diploid generation (2n); production of spores (n) through meiosis

gametophyte

haploid generation (n); production of gametes (n) through mitosis

stomata

specialized pores which support photosynthesis

anther

produces male reproductive cells or pollen

ovary

contains ovules, which contains the female reproductive structures

microsporangium

structure in anther where microspores are produced by meiosis

megasporangium

structure in ovule where megaspores are produced by meiosis

microspore

(n); mitosis → pollen grain (male gametophyte) → sperm (male gamete)

megaspore

(n); mitosis → embryo sac (female gametophyte) → egg (female gamete)

stigma

sticky part of a flower that catches/receives pollen

pollen tube

a tube that grows from a pollen grain down the style to the ovule, carrying sperm to the ovule for fertilization

pollination

transfer of pollen (male gametophyte) from the anther to the stigma

seed

• seed coat (2n); protective outer covering of a seed

  • endosperm (3n); nutritive tissue in the seed

    • embryo (2n); young developing plant

double fertilization

• a process in angiosperms where one sperm fertilizes the egg to form the 2n zygote, while the other sperm fuses with two polar nuclei to form the 3n endosperm

  • 1 sperm + egg → baby plant (embryo)

  • 1 sperm + 2 polar nuclei → nutrients (endosperm)

shoot system

above-ground parts of the plant; stems, leaves, flowers, fruits

root system

below-ground system; anchors the plants + water/minerals

tissue system

groups of tissues that work together to perform a function

organ

multiple tissue systems that work together to perform a function

leaves

photosynthesis

stems

support + transport

roots

anchorage + absorption

simple tissue

• mode of one cell type

  • ex: ground tissue; parenchyma, collenchyma, sclerenchyma

complex tissue

• made of multiple cell types

  • ex: epidermis, xylem, phloem, periderm

dermal tissue system

protection + exchange

vascular tissue system

transport + support

ground tissue system

storage + metabolism

hydrophytes

plans adapted to wet environments

mesophytes

plants that live in moderate water conditions

xerophytes

plants adapted to dry environments

cotyledon

embryonic leaf that provides nutrients to the developing embryo

synergids

two cells in embryo sac that help guide the pollen tube to the egg

monocot

(3s) flowering plant with 1 cotyledon (embryonic leaf), endosperm remains main food storage tissue

dicot

(4s or 5s) flowering plant with 2 cotyledons (embryonic leaves), nutrients move into cotyledons

seed dormancy

a period when a seed stays inactive and does not germinate when conditions aren't ideal

seed germination

• imbibition → seed absorbs water and swells

• seed coat breaks → water and oxygen enters

• metabolism begins → enzymes activate + nutrients used

• radicle emerges → first root grows downward

• shoot emerges → young shoot grows upward

complete flower

has all 4 flower whorls → (sepals → petals → stamens → carpels)

incomplete flower

missing at least 1 of the 4 flower whorls

guard cells

turgid; stoma opens

flaccid; stoma closes

mechanisms of movement

• diffusion

• osmosis

• mass flow

passive transport

• does not require energy; high → low concentration

• examples: diffusion, osmosis

active transport

• requires energy; low → high concentration

• examples: mineral ion uptake, sodium-potassium pump

transmembrane

movement through cell membranes (cell to cell)

symplastic

movement through cytoplasm via plasmodesmata

apoplastic

movement through cell walls and space between cells

ψS = osmotic potential

• dissolved solutes impact on water potential

• (more solute → lower water potential)

ψP = pressure potential

• physical pressure impact on water potential

• (more pressure → higher water potential)

transpiration + tension + cohesion

transpiration: water evaporates from the leaves

tension: evaporation creates a tension that pulls water upward

cohesion: water molecules stick together that pulls water upward

sink vs source

sink: uses or stores sugars (in)

source: makes and exports sugars (out)

macronutrients

• carbon, oxygen, hydrogen, nitrogen, phosphorus, sulfur

• potassium, calcium, and magnesium

micronutrients

iron and molybdenum

phytohormones

chemical messengers in plants that regulate growth/development

tropism

a plant’s directional growth response to a stimulus

axillary buds

small buds found in the angle between a leaf and the stem

phototropism

plant growth toward light

auxin

a plant hormone that promotes cell elongation

ethylene

plant hormone that promotes fruit ripening and dropping

aggregate fruit

a fruit that develops from one flower with multiple ovaries (raspberry, blackberry)

accessory fruit

a fruit in which tissues other than the ovary contribute significantly to the fruit (apple)

epicotyl

DICOT: embryo stem above the cotyledons; above root

hypocotyl

DICOT: embryo stem below the cotyledons; below shoot

coleoptile

MONOCOT: protective sheath that covers young shoot

colerohiza

MONOCOT: protective sheath that covers young root

hyphae

help aid in absorbing minerals and ions

growing root

root cap → cell division → elongation → maturation