BIOL 1108 Exam 2

What 2 domains do prokaryotes belong to?

bacteria and archaea

T/F: prokaryotes are monophyletic

False

how do prokaryotes reproduce

binary fission

How do phototrophs obtain energy?

sunlight

How do chemotrophs obtain energy?

chemicals

Autotrophs require ______ as a carbon source.

CO2

heterotrophs require _____ as a carbon source

organic nutrients

what are the 4 major modes of nutrition

photoautotrophy, chemoautotrophy, photoheterotrophy, chemoheterotrophy

plants and other photosynthetic organisms use what mode of nutrition

photoautotrophy

animals, fungi, and many prokaryotes use what mode of nutrition

chemoheterotrophy

only prokaryotes use what modes of nutrition (2)

chemoautotrophy (common) or photoheterotrophy (rare)

examples of good bacteria

cheese, yogurt, gave environment oxygen, gave plants chloroplasts, genetic engineering

examples of bad bacteria

chlamydia, lyme disease, food poisoning, necrosis

what are the 3 shapes of bacteria

spherical, rod-shaped, spiral

what are the 3 domains of life

Bacteria, Archaea, Eukarya

How are the 3 domains related?

None of the 3 is more primitive than the others- all are descended from the same common ancestor >3.5 billion years ago (LUCA)

What is the difference between gram-positive bacteria and gram-negative bacteria?

-gram-positive bacteria contain a thick peptidoglycan layer and stain purple

-gram-negative bacteria have a thin peptidoglycan layer that washes away, causing it to stain red

transformation

process of horizontal gene transfer that occurs due to the uptake

transduction

horizontal gene transfer that occurs due to transfer of DNA from one cell to another through a bacteriophage (viral) intermediate

Key characteristics of prokaryotes that are thought to be ancestral to cellular life

-no nuclei, usually a unicellular chromosome and often smaller plasmids- far less total DNA than eukaryotes

-most are microscopic and unicellular, although some species form colonies

-reproduce quickly by binary fission, some can divide every 1-3 hours

-short generation times mean rapid evolution

What kinds of habitats are archaea most likely found in?

in extreme environments such as high salt concentrations, extreme temperatures, methanogens

what are the shared, derived characteristics that link archaea more recently to eukaryotes than bacteria?

-several kinds of RNA polymerase

-introns present (in some genes in archaea)

-histones associated with DNA present (in some species in archaea)

prokaryotes are monophyletic, paraphyletic, polyphyletic (choose one)

paraphyletic

protista are monophyletic, paraphyletic, polyphyletic (choose one)

paraphyletic

green algae are monophyletic, paraphyletic, polyphyletic (choose one)

paraphyletic

eukaryotes are monophyletic, paraphyletic, polyphyletic (choose one)

monophyletic

examples of diseases/parasites in excavata taxonomic group

-giardia (campers diarrhea)

-trichomoniasis (vaginal parasite)

-african sleeping sickness (tsetse fly)

-chagas (kissing bugs in central/south american tropics)

-brain-eating amoeba (naegleria)

examples of diseases/parasites in SARs taxonomic group

-malaria
-toxoplasmosis

examples of diseases/parasites in bacteria*

-lyme disease

in which supergroup of eukaryotes did multicellularity independently evolve?

red and green algae (Archaeplastida)

alternation of generations

A life cycle in which there is both a multicellular diploid form (the sporophyte) and a multicellular haploid form (the gametophyte); characteristic of plants and some algae.

steps for transition from single-celled, diploid algae to*

?

what are the 3 major lineages of vascular plants

?

what ancestral characteristics are shared by archaea and bacteria

tiny, single-celled, have small genomes with no membrane-bound organelles

xylem transport

-tube of dead cells that conduct/transport water and other minerals

-water and dissolved minerals move from soil through plant body to atmosphere

-water and minerals in plant body move upward, from root to stem to leaf

phloem transport

living tissue that distributes sugars and Amino acids

What is transpiration?

-The loss of water vapor through the stomata of leaves.

-pulls water up from the roots

-more water lost=more pulled from roots=more nutrients delivered

Why is transpiration important?

-Water is required in the leaves for photosynthesis

-Water is required to enable cells to grow and elongate

-Water keeps cells turgid

-The flow of water carries useful minerals up the plant

-Evaporation of water keeps the plant cool.

why do plants have to be able to carefully regulate transpiration

to prevent excess water loss, especially during drought

what is primary growth in plants & what tissue is responsible?

-"elongation"

-plants grow lengthwise with shoot and root tip growth

-produced by apical meristems

what is secondary growth in plants and what tissue is responsible?

-growth in girth which thickens the shoots and roots of woody plants

-vascular cambium; xylem added to inside and phloem added to outside, sometimes in annual growth rings

what are the 2 products of double fertilization in angiosperms?

-zygote formed from one fertilized egg cell

-endosperm- formed by fusion of 1 sperm and 2 nuclei to form triploid tissue

major nonvascular plants

liverworts, hornworts, mosses

vascular spore plants

ferns, club mosses, lycopodium and horsetails

what are scale trees?

-tall plants topped with crowns of branches that sported long narrow leaves

when did scale tress exist

carboniferous period (299 MYA-359 mya)

what lineage did scale trees belong to

lycophytes

why were scale trees so important

they fell into swamps which created a huge build up of organic materials. these were compacted into coal, which allowed for the industrial revolution and the majority of our electricity still comes from breaking the chemical bonds formed by scale tree photosynthesis

4 major lineages of gymnosperms

conifers, cycads, ginkgo, gnetophytes

what is a seed?

diploid, multicellular embryo along with its food supply packaged in a protective coat

characteristics of basal angiosperms

-produce flowers (reproductive structures) and seed-protecting fruits

-mostly woody

-most widespread and diverse of all major plant groups

what is a cotyledon

an embryonic leaf in seed-bearing plants, one or more of which are the first leaves to appear from a germinating seed.

characteristics of basal monocots

-1 cotyledon

-parallel leaf veins

-floral organs in multiples of 3

characteristics of basal eudicots

-2 cotyledons

-net-veined leaves

-floral organs in 4s and 5s

what kinds of angiosperms do bees pollinate

most angiosperms, but some flowers hide their pollen and are made for "smart bees"

what kinds of angiosperms do butterflies and moths pollinate? why?

-thin, tubular flowers

-they have longer tongues to reach the stamens

what kinds of angiosperms do flies pollinate?

flowers that smell like fungus or dead animals

what kinds of angiosperms do bats pollinate

sturdy, white flowers that are fragrant at night

what kinds of angiosperms do hummingbirds pollinate

usually red, tubular, no fragrance