Module 4 - Biology

Diversity

The variety and differences among living organisms, particularly within the Kingdom Plantae.

Photosynthesis

The process by which green plants use sunlight to synthesize foods with the help of chlorophyll.

Terrestrial adaptations

Physical changes in plants that allow them to survive on land, including roots, cuticle, and stomata.

Autotrophs

Organisms that produce their own food through photosynthesis or chemosynthesis.

Alternation of generations

The reproductive cycle in plants where a multicellular haploid generation produces gametes that fuse to form a diploid generation.

Gametophyte

The haploid phase in the plant life cycle that produces gametes.

Sporophyte

The diploid phase in the plant life cycle that produces haploid spores.

Nonvascular plants

Plants that lack vascular tissue, such as mosses, liverworts, and hornworts.

Vascular tissue

Specialized tissue in plants for conducting water and nutrients, comprising xylem and phloem.

Xylem

Vascular tissue that transports water from roots to other parts of the plant.

Phloem

Vascular tissue that transports nutrients, such as sugars, throughout the plant.

Seed

A structure that contains an embryo and a supply of nutrients, encased in a protective outer coat.

Angiosperms

Flowering plants that produce seeds enclosed within a carpel.

Gymnosperms

Non-flowering plants that produce seeds on the surface of cones.

Coevolution

The process by which two or more species influence each other's evolution, such as flowering plants and pollinators.

Mutualistic relationship

A relationship between two species where both parties benefit.

Stomata

Pores on the surface of leaves that regulate gas exchange and water loss.

Carpel

The female reproductive part of a flower that contains ovary and ovules.

Anther

The part of a flower that produces pollen, the male gametophyte.

Cuticle

A waxy, water-tight covering on plant stems and leaves that aids in water conservation.

Carnivorous plants

Plants that derive some or most of their nutrients from trapping and consuming animals.

Evolution

the change in the organisms characteristics over time

Speciation

formation of new species, change in existing species

phylogenetic trees

display the evolutionary relationships of different species

What does evolution result in?

Huge diversity in all organisms on earth

What is fossil evidence?

Preserved remains or traces that can be dated back compared to other fossils. It demonstrates history of evolutionary change

Homologous structures

similar structure in closely related organisms

Do organisms go through the same basic developmental patterns?

Yes

Molecular evidence

comparing DNA in a gene, or a type of protein.

Do closely related species have more similar genes/proteins?

yes

what was the observation on Galapagos islands?

finches have different beak shapes depending on feeding habits

DNA of finches was compared:

Adaptive radiation - Finches descended from a common ancestor, with modifications that were adaptive for different food sources

Mutations

create changes and new traits in organisms

Natural selection

individuals with adaptive traits in an environment will survive and reproduce more frequently than those without. Population gradually evolves.

Sexual selection

individuals with traits that are advantageous for securing mates will out-reproduce those without

Artificial selection

Selective breeding, humans breed other plants/animals for particular traits

‘runaway’ sexual selection can result in extremes:

sex-related traits may be disadvantageous for survival

Isolating mechanism

prevents different species from cross-breeding

Geographic isolation

species are found in different areas, separated by a barrier

Ecological isolation

species are in the same area but occupy different habitats (Niches)

Temporal isolation

species reproduce in different seasons or times of the day

behavioral isolation

species have different mating rituals

mechanical isolation

Different species reproductive parts cannot fit together

Gamete isolation

gametes from different species are not able to come together (egg and sperm cannot fuze)

hybrid inviability (or sterility)

hybrids of different species are not able to survive or cannot reproduce (zonkey)

convergent evolution

independent evolution of similar traits in unrelated organisms

Ex: shark/dolphin - tapered body form, fins

Analogous structures

structures that are functionally similar but evolved independently

Ex: Wings for flight

Biological classification

categorizes organisms into groups (taxa) based on similar features

scientific name

specific names include genus then species

Biological classification changes as more information is gathered

Recent changes due to DNA technology

Bacteria:

Bacteria

Archaea

Archaea

Eukarya

protista, plantar, fungi, animalia

Kingdom bacteria

Unicellular prokaryotes and the most abundant organisms on the earth

Kingdom bacteria different features:

photosynthesis, nitrogen-fixation, have a flagellum

Kingdom bacteria relationship with humans:

pathogens - cause disease, symbiosis - benefit human hosts (gut bacteria), bioremedation - break down toxic compounds, food products

Kingdom archaea

Unicellular prokaryotes, ‘extremophiles’ - live in extreme conditions (hot, cold, salty, pH)

Kingdom protista

members of protista are very diverse, do not all share the same common ancestor = ‘catch all kingdom’

Features of different kingdom protista members:

outer cell walls, silica surfaces

may have cilia, one or more flagella

reproduce asexually or sexually

Unicellular, form colonies or multicellular

may be photosynthetic

Notable protists:

algae - food, agar

diatoms - have glassy shells

Paramecium - pond dwellers

Dinoflagellates - cause red tides

phytoplankton - base of aquatic food webs

Some protists cause disease

Giardia intestinal is (beaver fever)

Trichomonas vaginalis (trichommoniasis)

plasmodium (malaria)

amoeba sp. (encephalitis, gastroenteritis)

toxoplasma gondii (toxoplasmosis)

fungi kingdom features:

reproduces sexually and asexually

often use spores to disperse

yeast reproduce by budding off

notable kingdom fungi:

mycorrhizal fungi - symbiosis with plants

Lichen - symbiosis with an alga

Yeast - fermentation

penicillium fungi - antibiotics

virus

an acellular infectious particle that is an obligate parasite

Basic structure of viruses:

genetic material (RNA or DNA) surrounded by a protein coat (capsid)

naked virus - no phospholipid envelope

Eveloped virus - phopholipid envelope surrounding capsid

cytopathic effects

virus induced damage to cells

Where are viruses alive?

metabolism - no

cells - no

DNA - yes

replication - no

evolution - yes

lytic cycle

virus infects cell, replicates and destroys infected cell

lysogenic cycle

virus infected cell, pastes DNA into hosts genome, is copied with entire cell

Rhinovirus

causes common cold

influenza

causes flu

HIV

Leads to AIDS

HPV

produces warts

hepatitis B

liver inflammation

ebola virus

cause hemerrohagic fever

roots

used to absorb nutrients and mineral in soil

Kingdom Plantae:

autotrophs, multicellular, terrestrial and aquatic, share a common ancestor with green algae

Four main plant groups:

nonvascular plants - mosses

seedless vascular plants - ferns

gymnosperms - conifers, cycads

angiosperms - flowering plant

Nonvascular plants:

mosses, liverworts, hornworts

small, lack vascular tissue to grow tall

found in moist, shady habitats

seedless vascular plants:

ferns and club mosses

vascular tissue allows for tall growth

found in moist, shady habitats

advantages of seeds:

allow dispersal, dormancy, nourishment during germination,

male cones produce

pollen

female gymnosperms cones produce

seeds

flower

reproductive structure, pollination mechanism

advantages of flowers:

petals attract pollinators, anthers produce pollen, carpel contains ovary with an egg, seeds produced in carpel become surrounded by fleshy fruit

angiosperms:

male flowers produce pollen, female flowers produce carpel, fertilization produces an embryo within a seed within the carpel

What do all animals have in common?

Heterotrophs, no cell walls, multicellular, tissues, active movement, diverse in form and habitat, sexual reproduction, embryonic development

Poriferans (sponges):

stationary, filter-feeders. No symmetry or different tissue types choanocytes with flagella move water through the sponge

cnidarians:

have radial symmetry and true tissues. Carnivorous

Ex: medusae - jellyfish, polyps - hydra, coral, sea anemone

radial symmetry

all three planes are symmetrical, no specialized ends

bilateral symmetry

one plane of symmetry, sensory organs concentrated in front

platyhelminthes (flatworms):

parasitic, freshwater, and marine flatworms

bnilateral symmetry and three tissue types

What are the three tissue types for flatworms?

endoderm - forms the gut

mesoderm - forms muscles and organs

ectoderm - outer skin

coelom

fluid filled body cavity within mesoderm

acoelomates

no coelom

pseudoceolomates

have a partial coelom

coelomates

have coelom. Have a circulatory system. independent organ function

unsegmented worms

pseudocoelomates

parasitic

grow by molting (shed outer protective layer)

protosomes

all coelomates up to arthropods. Blastopore develops into a mouth