Plants and Society Midterm

archaea

prokaryotes known for living in extreme environments

bacteria

most prokaryotes

prokaryotes

cells don’t have a nucleus or membrane-bound organelles

eukaryotes

cells have nucleus and membrane-bound organelles

protists

all other eukaryotes besides fungi, plants, and animals

green algae

move straight into the adult stage from the zygote stage with no embryo formation; have chlorophyll A and B

zygote

fertilized egg; eukaryotic cell formed after fertilization between gametes

embryophytes (land plants)

zygote forms an embryo after fertilization

embryo

multicellular structure that develops from the zygote

diploid cells (2n)

have 2 sets of chromosomes, one from each parent

haploid cells (n)

gametes with only one set of chromosomes created when diploid cells undergo meiosis

alternation of generations

plants alternate from gametophyte to sporophyte throughout their life cycle; can be used to tell about the history of land plants and to distinguish different divisions from each other

sporophyte

diploid phase of the life cycle where plants produce haploid cells via meiosis; dominant stage in more evolved plants

gametophyte

haploid phase of the life cycle where plants produce haploid gametes via mitosis; dominant stage in less evolved plants

embryophyte divisions from least to most evolved

bryophytes, ferns, gymnosperms, angiosperms/magnoliophytes

angiosperrm/magnoliophyte classification features

produce flowers, have ovaries that surround ovules

ovules

structure in flower that produce seeds in angiosperms

endosperm

food for seeds

habitat of angiosperms/magnoliophytes

everywhere, most widespread vegetation on Earth

egg-owning structure in angiosperms

ovary

sperm-owning structure in angiosperms

anther

generative cell

develops into sperm; haploid

tube cell

develops into the pollen tube; haploid

pollen tube

tunnel for sperm to move into the ovary of an angiosperm; haploid

sperm-owning structure in gymnosperms

smaller cone

egg-owning structure in gymnosperms

larger cones

sperm-owning structure in bryophytes and fern and fern like plants

antheridium

egg-owning structure in bryophytes and fern and fern like plants

archegonium

sorus

diploid (sporophyte) reproductive structure in fern and fern like plants

prothallium

free-living gametophyte of fern and fern like plants

cell theory of biology

cells are a basic unit of life, all organisms are composed of cells, and cells arise from preexisting cells

carbohydrates

function as source of energy (starches, sugars) and give structure to the plant (cellulose)

proteins

serve as enzymes, structural material, regulatory molecules, or transport molecules

lipids

structural (make up cell membrane), component of hormones

nucleic acids

make up DNA and RNA

function of the cell wall

support and protect the cell; contains cellulose

secondary cell wall

made of lignin, not in all cells

lamella

water between different cells

plasmodesma

small pores that connect cytoplasms of different cells; used for nutrient and water transport

endosymbiotic theory

all complex eukaryotic cells with organelles evolved by one cell absorbing another and gaining its abilities

evidence for endosymbiotic theory

cells can’t make the organelles on their own, organelles have a double membrane, mitochondria have similar DNA to ancient cells scientists suspect they evolved from

plastids

organelles found in plant but not animal cells that originate from endosymbiosis

function of chloroplasts

photosynthesis

pigments contained in chloroplasts

chlorophyll, carotene, xanthophyll

function of leucoplasts

store energy in the form of starch; abundant in storage organs

function of chromoplasts

contain pigments (carotenoids) that make plant organs attractive to animals

uses of carotenoids

dyes, medicine, and nutrition (vitamin A, antioxidants)

function of the central vacuole

stores energy/nutrients (carbohydrates), stores waste (actual waste or calcium oxalate crystals), can contain pigments (anthocyanin)

plant propagation

the process of increasing the number of plants of a particular species or cultivar

importance of sexual propagation

increases genetic diversity through fertilization and crossing over

Ecological importance of asexual propagation

allows for quick reproduction without relying on a partner; advantageous for early succession species

societal importance of asexual propagation

allows farmers to keep desired traits, plants grow faster than from seed, is an abundant resource

types of asexual propagation

leaf cutting, stem tip cutting, tissue culture, grafting

leaf cutting

cut only the leaf blade and part of the petiole with active meristematic tissue

stem tip cutting

cut the apital meristem tissue and one full leaf from the mother plant

tissue culture

grow pieces of meristem tissue or cells in a growth medium using specialized equipment and a glass tube

grafting

joining the lateral meristem tissue of 2 different species

what is a beet anatomically

root

what is celery anatomically

petiole

what is cabbage anatomically

leaf

what is a potato anatomically

stem (tuber)

what is onion and garlic anatomically

storage organ leaves

what is rhubarb anatomically

leaf with long petiole

what is pumpkin anatomically

fruit

what is turnip anatomically

stem

what are brussles sprouts anatomically

axillary buds

tissues

groups of specialized cells performing specific functions

types of tissues

meristem, dermal, ground, vascular

meristem tissue

region of active cell division where plant growth is localized and cells haven’t yet differentiated into specific tissue types

apical meristem

located at the terminal bud and root caps; responsible for primary growth

lateral meristem

includes vascular and cork cambium located in stems and roots; responsible for secondary growth

vascular cambium

meristem tissue that gives origin to secondary vascular tissue

cork cambium

meristem tissue that gives rise to cork cells

dermal tissue

outermost layer of a plant; composed of epidermis and periderm

epidermis

top layer of cells; composed of cuticle, trichomes, and stomata

cuticle

waterproof layer of lipids secreted by epidermal cells that prevents water loss through evaporation

trichomes

hairs made of elongated epidermal cells that deter herbivores

stomata

pores in epidermis cells between two guard cells that facilitate gas exchange and are critical for photosynthesis

guard cells

only cells in the epidermis that have chloroplasts and can photosynthesize

periderm

composed of the cork cambium and cork cells; replaces epidermis during secondary growth

cork cells

dead cells whose walls contain a fatty substance that prevents water loss and protects underlying tissue

ground tissue

composed of parenchyma, collenchyma, and sclerenchyma

parenchyma

versitile storage tissue with many different functions

collenchyma

provide structure and support

sclerenchyma

composed of fiber cells and sclereids; provide protection, structure, and support

fiber cells

elongated cells containing lignin that die after reaching a certain level of maturity; for structure and support

sclereids

provide defense to the plant

vascular tissue

composed of xylem and phloem

xylem

transports water and nutrients from soil to other plant parts

phloem

transports sugars and products of photosynthesis to other plant parts

3 principal vegetative organs

stems, roots, leaves

stems

support the plant and transport water and organic material

roots

anchor the plant and absorb water and nutrients from the soil

leaves

main photosynthetic structures

monocots

have one cotyledon and no secondary growth

dicots

have 2 cotyledons; woody dicots have secondary growth

differences between monocot and dicot stems

monocots have lemur face and distributed vascular bundles; dicot roots have layers with phloem above xylem, vascular bundles around only the edge, and a pith (parenchyma)

2 types of root systems

fibrous roots and tap roots

fibrous roots

multiple roots come from the same plant; monocots

tap roots

one main root with lateral roots coming out of the main root; dicots