Download Ecology Exam Review

Ecology
Exam Review
Ecology
• Earth Sciences
• The Biosphere
• Ecosystems and Communities
• Populations
• Branches of Earth Science
• Cells
• Cell Structure
• Photosynthesis
• Cell Respiration
• States of Matter
• Lab Safety
• Earths Surface
• Maps
• Topography
• Landforms
Ecology
• The scientific analysis and study of interactions among organisms and their
environment. It is an interdisciplinary field that includes biology and Earth
science. Ecology includes the study of interactions organisms have with
each other, other organisms, and with abiotic components of their
environment.
• Ecologists seek to explain:
• Life processes, interactions and adaptations
• The movement of materials and energy through living communities
• The successional development of ecosystems
• The abundance and distribution of organisms and biodiversity in the
context of the environment.
Biosphere
• Global sum of all ecosystems
• Closed system that self regulates
Biome
• Formation of plants and
animals that have
common characteristics
due to similar climates
and can be found over a
range of continents.
• Biomes are distinct from
habitats, because any
biome can be comprised
of a variety of habitats.
Ecosystems
• Each ecosystem is made up of the following parts
• Producers – Make their own food (energy)
• Plants
• Small organisms
• Consumers – Cannot make their own food.
• Primary Consumers - Eat Producers (Herbivores)
• Secondary Consumers – Eat primary Consumers and / or Producers (carnivores,
omnivores)
• Decomposers – Break down dead or decaying organisms
• Bacteria, Fungi, Earthworms
Food Chain
• Direct line from plant (bottom) to largest or most advance (top) entity
in an ecosystem.
Food Web
• Lines go in several
directions
• Connected food chains
• Shows everything
within an ecosystem
and what it eats or
what eats it
Populations
• Group of organisms, which live in a particular area and can interbreed
• Interbreeding is generally more common than cross-breeding with
individuals from other areas
• Populations are affected by Environmental Impacts
• Wars
• Drops in childbirths, production of products and crops
• Baby booms
• Diseases
• Water, Crop, or food product issues
• Natural Disasters
Cell Structure
Plant
Cell
Photosynthesis
• What three things are reactants (are used) in the photosynthetic
process?
• sunlight, carbon dioxide, and water
• What two substances are products (get made) in the photosynthetic
process?
• oxygen and glucose
Photosynthesis
• There are two phases in photosynthesis.
• light-dependent reactions
• the Calvin cycle
• The Calvin cycle is the principal mechanism that leads to the conversion of carbon dioxide into sugars by
plants, algae, photosynthetic bacteria, and certain other bacteria that use chemicals as an energy source
instead of light.
The Calvin cycle, also known as the Calvin Benson cycle, is an integral part of the process of
photosynthesis in plants, algae, and photosynthetic bacteria. Named after its discoverer, Melvin Calvin of
the University of California at Berkeley, its principal product is a three-carbon compound called
glyceraldehyde 3-phosphate, or PGAL. Sugars are synthesized using PGAL as a starting material.
Light, absorbed by chlorophyll, is used to synthesize the high-energy compounds adenosine triphosphate
(ATP) and reduced nicotinamide adenine dinucleotide phosphate (NADPH). Chlorophyll and the enzymes
that are used for synthesis of ATP and NADPH are associated with internal membranes in all
photosynthetic cells.
The ATP and NADPH, once formed, are released from the membrane-bound enzymes and diffuse into
the surrounding solution inside the cell. The Calvin cycle takes place in this solution, using the ATP and
NADPH molecules as a source of energy to drive the conversion of carbon dioxide into PGAL.
Calvin Cycle
Photosynthesis
• The light-dependent
reactions use
sunlight energy and
water. The water is
obtained through the
roots. (Reminder:
water enters through
the roots, and travels
through the xylem to
the rest of the plant)
• Xylem - The basic
function of xylem is
to transport water,
but it also transports
some nutrients.
Photosynthesis
• The light-dependent reactions produce oxygen and energy. The
oxygen leaves the leaf through the stomata.
• Stomata - The stomata are pores in leaves. They are responsible for gas
exchange. Carbon dioxide enters through the stomata.
• The light-dependent reactions happen in the thylakoids of the
chloroplast.
• The thylakoid membranes of a chloroplast is an internal system of
interconnected membranes, that carry out the light reactions of
photosynthesis. They are arranged into stacked and unstacked regions called
grana and stroma thylakoids, respectively
Photosynthesis
• The Calvin cycle uses the energy from the light reactions, as well as
the input of carbon dioxide The big product of following the Calvin
cycle is glucose, which has the chemical formula C6H12O6.
• The Calvin cycle happens in the stroma of the chloroplast.
• This is the complete balanced equation for photosynthesis.
• 6 COs + 6 H2O + energy  C6H12O6 + 6 O2
• carbon dioxide + water + sunlight  glucose + oxygen
Photosynthesis
• What is the primary pigment responsible for absorbing the light
energy for photosynthesis?
• chlorophyll is the primary pigment
• Why do most plants appear green?
• Chlorophyll reflects green light, and absorb other colors like red, blue, and
violet. We see what is reflected from objects.
• Chlorophyll is contained in disc-shaped structures in the chloroplasts
called thylakoids. A stack of these discs is called a granum.
Photosynthesis
Photosynthesis
• Gas exchange is necessary for photosynthesis. How does carbon
dioxide gas get in and oxygen gas get out of the leaves?
• The gases move in an out through the stomata, which are tiny holes on the
bottom side of leaves.
• What layers of cells in the leaf perform photosynthesis?
• the mesophyll layers – palisade mesophyll and spongy mesophyll
Cellular Respiration
• Cellular respiration is the set of metabolic reactions and processes that take place in the cells of
organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and
then release waste products. The reactions involved in respiration are catabolic reactions, which
break large molecules into smaller ones, releasing energy in the process, as weak so-called "highenergy" bonds are replaced by stronger bonds in the products. Respiration is one of the key ways
a cell gains useful energy to fuel cellular activity. Cellular respiration is considered an exothermic
redox reaction which releases heat. The overall reaction occurs in a series of biochemical steps,
most of which are redox reactions themselves. Although technically, cellular respiration is a
combustion reaction, it clearly does not resemble one when it occurs in a living cell due to slow
release of energy from the series of reactions.
• Nutrients that are commonly used by animal and plant cells in respiration include sugar, amino
acids and fatty acids, and the most common oxidizing agent (electron acceptor) is molecular
oxygen (O2). The chemical energy stored in ATP (its third phosphate group is weakly bonded to
the rest of the molecule and is cheaply broken allowing stronger bonds to form, thereby
transferring energy for use by the cell) can then be used to drive processes requiring energy,
including biosynthesis, locomotion or transportation of molecules across cell membranes.
States of Matter
Gas
Evaporation
Sublimation
Solid
Condensation
Liquid
Melting
Freezing
Lab Safety
• Fire
• Chemical Burns
• Weights
• Safe Handling of Equipment
• Glass
• Metal
• Labels
Models of Earth
G 1-2
Maps and Globes
• Map –flat model of all or part of Earth’s
surface as seen from above
• Globe – a sphere that represent Earth’s entire
surface
– Correctly shows the relative size and shape of
landmasses and bodies of water
– Both are drawn to scale and use symbols to
represent topography and other features
G 1-2
Parts of the Map
Scale – relates distance on a map to a distance
on the Earth’s surface. Often given as a ratio
Symbols – pictures that represent features
Key – legend, a list of symbols used on the map
Compass Rose – used for direction on a map.
The top of a map is usually North
G 1-2
Earth’s Reference
System
Equator – imaginary line divides the Earth into Northern and
Southern hemispheres.
Hemispheres= ½ of the sphere that is planet Earth.
Prime Meridian – imaginary line that makes a half circle from
the North Pole and the South Pole. It divides the earth into
the Western and Eastern hemispheres
Degree – 1/360 of the way around a full circle.
G 1-2
Locating Points
on the Earth’s
Surface
Latitude – distance north or south of the equator.
The equator is 0 °. North Pole is 90 °north, South
Pole is 90 ° south.
Longitude – distance in degrees east or west of the
Prime Meridian. Prime meridian is 0°. Half way
around the sphere is 180° east or west.
G 1-2
Map Projections- A framework of lines that
show land masses on a flat surface
Mercator projection lines
are flat and straight. Land
masses are distorted.
G 1-2
Equal Area projection:
correctly shows the
sizes of Earth’s
landmasses.
Landmasses at the
edges are distorted.