BIO Ch 17: The History of Life

in 1953, the _____-_____ experiment showed a possible origin of organic molecules

Miller-Urey

one species of _____ harbors symbiotic algae, supporting the endosymbiotic hypothesis

Paramecium

animal diversity arose in the ____ Era

Precambrian

Earth may have once been an _____ world

RNA

_____ can act as a catalyst

RNA

_____ may have been the first self-reproducing molecule

RNA

_____ may have served as both an information-carrying molecule and an enzyme catalyst for its own replication

RNA

by the ____ period, life in Earth's seas included an array of anatomically complex animals

Silurian

early amphibians had _____ ____, which are like primitive lungs

air sacs

_____ evolved from lobe-finned fishes

amphibians

the first organisms were _____ (aerobic, anaerobic) prokaryotes and probably absorbed nutrients from the _____

anaerobic environment

flowering plants enticed _____ to carry pollen

animals

the first animals to move onto land were ____ (the group that today includes insects, spiders, scorpions, centipedes, and crabs)

arthropods

when animals became adapted to life on dry land, _____ were the first to invade land

arthropods

reptiles have trouble retaining _____ _____

body heat

_____ may have catalyzed the formation of larger organic molecules

clay

_____ change contributed to mass extinctions

climate

____ protected their developing seeds inside cones

conifers

_____ were the earliest seed-bearing plants

conifers

one cause of climate change is _____ drift

continental

early amphibians had muscular fins that allowed

crawling

_____ dominated the earth for millions of years

dinosaurs

some plants became adapted to life on ____ land

dry

the _____hypothesis proposes that early eukaryotic cells acquired the precursors of mitochondria and chloroplasts by engulfing certain types of bacteria

endosymbiont

the _____ ______ proposes that early eukaryotic cells acquired the precursors of mitochondria and chloroplasts by engulfing certain types of bacteria

endosymbiont hypothesis

the _____ of arthropods facilitated survival

exoskeleton

____ provided support for animals' bodies and protection from predators

exoskeletons

_____ are hard outer coverings that help protect animals that have them

exoskeletons

_____ improved mobility by providing hard surfaces to which muscles attached. These attachments made it possible for animals to use their muscles to move appendages used to swim through the water or crawl over the seafloor

exoskeletons

evolutionary history has been marked by periodic mass _____

extinctions

insulating _____ retain body heat for birds

feathers

____ proved to be faster than invertebrates, with more acute senses and larger brains. Eventually, they became the dominant predators of the open seas

fish

feathers evolved for ____

flight

insulating _____ retains body heat for mammals

hair

the time it takes for half of a radioactive element's nuclei to decay at a rate that is independent of temp., pressure, or chemical compound is called its _____ _____

half life

Each radioactive element decays at a rate that is independent of temperature, pressure, or the chemical compound of which the element is a part. The time it takes for half of a radioactive element's nuclei to decay is called it's ____ ____

half-life

the internal membranes of eukaryotes may have arisen through _____ of the plasma membrane

infolding

pollination of plants is facilitated by _____

insects

the internal membranes of eukaryotic cells may have originally arisen through ____ ____ of the cell membrane of a sing-celled predator

inward folding

_____ and _____ can form membrane-like vesicles

lipids proteins

a support of the endosymbiont hypothesis comes from ____ ____, organisms alive today that are similar to hypothetical ancestors and this help show that a proposed evolutionary pathway is plausible

living intermediates

_____ bear live young and have mammary glands to nourish them

mammals

_____ invertebrates dominated during the Precambrian Era

marine

_____-like vesicles may have enclosed ribozymes

membrane

some organisms acquired _____-enclosed organelles

membrane

_____ and _____ may have arisen from engulfed bacteria

mitochondria chloroplasts

coevolution of predator and prey favored animals that were more ____ than their predecessors

mobile

_____ and _____ were the first plants to evolve on land

mosses ferns

some algae became _____

multicellular

the first living things arose from _____ things

non living

aerobic metabolism arose in response to the _____ crisis

oxygen

_____ increased the amount of oxygen in the atmosphere

photosynthesis

_____ bacteria set the stage for the evolution of an oxygen-rich environment

photosynthetic

the potential rewards for terrestrial life were especially great for ____

plants

continental drift is caused by _____ _____, in which the Earth's surface moves slowly and land changes places

plate tectonics

seed plants encased sperm in _____ grains

pollen

organic molecules can form spontaneously under ______ conditions

prebiotic

the period in which life began is known as the _____ era

precambrian

_____ favored the evolution of improved mobility and senses

predation

______ are organisms whose genetic material is not enclosed in a membrane-bound nucleus AND they lack other membrane-bound organelles

prokaryotes

the first cells to arise in Earth's oceans were _____, cells whose genetic material was not contained within a nucleus

prokaryotes

a ____ is structurally similar to a cell but not alive

protocell

if a vesicle happened to surround the right ribozymes, could explain the possible origins of cell-like structures called

protocells

_____ evolved from amphibians

reptiles

_____ evolved shelled eggs, water-resistant skin, and fully-functional lungs

reptiles

_____ gave rise to mammals

reptiles

one group of _____ evolved into birds

reptiles

_____ are RNA molecules that can catalyze a variety of reactions involving RNA

ribozymes

_____ improved mobility and protection

skeletons

primitive land plants retained swimming ____ and required water to reproduce

sperm

in the mid-1800s, the idea of _____ _____ was refuted by Louis Pasteur and John Tyndall

spontaneous generation

life was thought to have developed from living and nonliving matter through _____ _____

spontaneous generation

evidence for the endosymbiont hypothesis is ____ (strong/weak)

strong

early amphibians were still dependent on _____ for survival and reproduction

water

once _____ was available, the prebiotic evolution that ultimately led to the first living organism could begin

water

primitive land plants were still dependent on _____ for reproduction

water

____-____ coatings on above ground parts (of land plants) reduced water loss by evaporation, and rootlike structures delved into the soil, mining water and minerals

water-resistant

during the ____ period, the flowering plants appeared, having evolved from a group of conifer-like plants

Cretaceous

the earliest seed-bearing plants appeared in the late ____ period and produced their seeds along branches, without any specialized structures to hold them

Denovian

* 2 ways an organism larger than a millimeter in diameter can survive: 1.) have a low metabolic rate so that it doesn't need much oxygen or produce much carbon dioxide; 2.) be multicelluar

...

* Earth was cool enough for water to exist in liquid form by 4.3 billion years ago. Once liquid water was available, the prebiotic evolution that ultimately led to the first living organisms could begin

...

* Eventually, the endosymbiotic bacterium lost its ability to live independently of its host and the mitochondrion was born. It then captured a photosynthetic bacterium and again failed to digest its prey. The bacterium flourished in its new host and gradually evolved into the first chloroplast

...

* The eggs of seed plants were retained on the parent plant and the sperm were encased in drought-resistant pollen grains that were carried by the wind from plant to plant. When the pollen grains landed near an egg, they released sperm cells directly onto living things

...

* The evolution of efficient movement was often associated with the evolution of greater sensory capabilities and more complex nervous systems. Senses for detecting touch, chemicals, and light became highly developed, along with nervous systems capable of handling the sensory information and directing appropriate behaviors

...

* extra thick walls (of land plants) surrounding certain cells enabled stems to stand erect

...

* multicellularity provided 2 advantages: 1.) large, many-celled algae would have been difficult for single-celled predators to engulf; 2.) specialization of cells would have provided the potential for staying in one place in the brightly lit waters of the shoreline, as rootlike structures burrowed in sand or clutched onto rocks, while leaflike structures floated above the sunlight

...

* significant amounts of oxygen first appeared in the atmosphere about 2.3 billion years ago, produced by bacteria that were probably very similar to modern cyanobacteria

...

* some algae gave rise to the first multicellular land plants

...

* specialized cells (of land plants) formed tissues (called vascular tissues) that contained tubes to conduct water from roots to leaves

...

* the earliest cells were primitive anaerobic bacteria

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* the earliest plants were restricted to swamps and marshes or to areas with abundant rainfall; here the sperm and eggs could be released into the water, and sperm could swim to reach an egg

...

* the full range of modern invertebrate animals does not appear in fossil record until the Cambrian period, marking the beginning of the Paleozoic era, about 542 million years ago

...

* the oldest fossil organisms found so far are in rocks that are about 3.4 billion years old

...

* the plants that first colonized the land would have had ample sunlight, untouched nutrient sources, and no predators

...

* water-based photosynthesis converts water and carbon dioxide to energetic molecules of sugar, releasing oxygen as a byproduct; the emergence of this new method for capturing energy introduced significant amounts of free oxygen to the atmosphere for the first time

...

*photosynthesis requires a source of hydrogen

...

the rise of eukaryotes began about _____ billion years ago

1.7

the oldest fossil organisms found so far are in rocks that are about _____ billion years old

3.4

almost all of the major groups of animals on Earth today were already present in the early _____

Cambrian

the _____ period was characterized by vast forests of giant tree ferns, club mosses, and horsetails

Carboniferous