Biology ReviewTake out your first nine weeks

study guide.

First Semester Review

Experimental Design• In a controlled experiment only ONE variable can change.

The one variable that changes is called the • Independent variable.• Which variable is the result of the experiment?• Dependent variable• Which group includes the independent variable?• Experimental group• Which group does NOT include the independent variable?• Control group• Why is a control group needed?• To have something to compare the results to.

When graphing…

• Remember DRY/MIX• Dependent/responding on the Y axis• Manipulated/independent on the X axis

Symbols

Microscopes

• How do you figure total magnification?• Eyepiece X objective• What is the FIRST part of the microscope you

should adjust? Why?• The diaphragm b/c it controls the amount of

light that enters the microscope.• Why do you cover a microscope?• Keep dust away

Chemistry…• What type of chemical bond occurs when

electrons are shared?• Covalent – ex: water• What type of chemical bond occurs when

electrons are transferred?• Ionic – ex: NaCl, NaBr, CaCl• When an atom gains electrons it becomes – • A negatively charged ion• When an atom looses electrons it becomes-• A positively charged ion

Chemistry…• pH means potential of Hydrogen• What type of solution produces H+ ions and is

found below 7 on the pH scale?• Acids• What type of solution produces fewer H+ ions

and is found above 7 on the pH scale?• Base or alkaline• What type of substance reacts with strong

acids or bases to prevent sharp, sudden changes in pH?

• buffers

Properties of Water…• Polar covalent bonds are what holds a water

molecule together.• What kind of bond is found between water

molecules and makes water extremely cohesive?• Hydrogen bonds• Cohesion is water sticking to water. Cohesion gives

water surface tension, which is what allows insects to be able to walk on water.(paperclip)

• Adhesion is water sticking to other substances.• Water is the universal solvent.• Water has a high specific heat.

Organic Molecules…

• Contain CARBON.• All living things contain carbon.• THE ELEMENT AROUND WHICH ALL LIFE

EXISTS IS CARBON!!!

Carbohydrates…• ALL SUGARS AND STARCHES ARE CARBS.• Living things use carbohydrates as their main

source of energy.• The monomer of a carbohydrate is a

monosaccharide.• Examples of monosaccharides are: glucose,

fructose and galactose• Polysaccharides are many sugars. • Examples of polysaccharrides are: chitin (cell

walls of mushrooms), cellulose (cell walls of plants), glycogen (animal starch)

Lipids…• The monomer of a lipid is a glycerol and three

fatty acids.• Examples of lipids include: fats, oils, waxes (on

cuticle of leaves), triglycerides and cholesterol.• Functions of lipids:– Used by living things as a source of STORED energy– Cushioning and insulation (blubber in polar bears)

Proteins…• The monomer of a protein is an amino acid.• Amino acids are made of a carboxyl group, an

amino group and an R group.• The sequence of amino acids determines the

protein.• The R group determines the amino acid.• Examples of proteins: collagen and enzymes• Functions of proteins:– Fight disease– Repair bone and muscle– Act as enzymes to speed up chemical reactions

Nucleic Acids…• The only examples of nucleic acids are DNA

and RNA.• The monomer of a nucleic acids is a

nucleotide.• Nucleotides consist of a 5 Carbon sugar, a

phosphate group and a nitrogenous base.• Functions of nucleic acids are:– Determines hereditary information– Passes on genes from one generation to the next– Carries information to ribosomes to tell them how

to make the proteins

Ecology…• The scientific study of interactions between

organisms and their environment is called ecology.

• species populations communities ecosystems biomes biosphere

• A species is a group of organisms that are so closely related that when they mate, they produce FERTILE offspring.

• Biotic factors: living factors ex: animals, plants, fungi

• Abiotic factors: non-living factors ex: water, soil, temperature, sunshine, etc.

• Name some abiotic factors that affect plants.• Sunlight, carbon dioxide, pH• Name some biotic factors that affect plants.• Grazing animals, mold, other bacterial or fungal

diseases• Biological magnification – when a toxic substance

increases in toxicity as it progresses through a food chain or web.

• Who is hurt MOST by biological magnification?• Tertiary consumers (top-level consumers)• Name some things that can cause a deer

population to increase quickly….. • Shorter hunting seasons

Ecology…• Autotrophs or producers – make their own food• Heterotrophs or consumers – can not make their own food.• A trait that promotes an organism’s survival in nature is called

an adaptation.• A BEHAVIORAL ADAPTATION that helps bears survive the

winter is …• Hibernation.• In each food chain or web, how much energy is passed from

one trophic level to the next?• 10%• Who receives the LEAST amount of energy?• Top-level carnivore• Who receives 100% of the sun’s energy?• autotrophs

Ecology…• What type of organism is a producer that does

not need light to make food?• Chemosynthetic bacteria• What shows the relative amount of energy or

matter contained within each trophic level in a given food chain or web?

• Ecological pyramid• The total amount of living tissue in a given

trophic level is called• Biomass.

Ecology…• Energy flows in one direction from the sun to

autotrophs to heterotrophs.• Unlike the one-way flow of energy, matter is

recycled within and between ecosystems.• Elements pass from one organism to another

and among parts of the biosphere through closed loops called

• Biogeochemical cycles.• Burning fossil fuels affects the CARBON cycle.• What is the main type of decomposer?• bacteria

Nitrogen in the biosphere…

• Nitrogen gas in the atmosphere is converted into ammonium nitrate by bacteria in the soil. This process is called

• Nitrogen fixation.• Ammonium nitrate is converted back into free

nitrogen gas by soil bacteria in a process called• Denitrification.

Ecology…

• Any time a nutrient limits primary productivity, it is called a

• Limiting nutrient.• A series of predictable changes that occur in a

community over time is called• Ecological succession.• Ecosystems change over time, especially after

disturbances, as some species die out and new species move in.

Succession• Succession that begins in an area where NO soil

exists is called• Primary succession. • Ex: after a volcanic eruption• The first species to colonize barren areas are called• Pioneer species.• What is often the pioneer species?• Lichen – a symbiotic relationship b/w a fungus and

an algae• Grasses would be the next population to populate

the area.

Succession..

• Succession that begins in areas where soil exists is called

• Secondary succession• Ex; after a forest fire or when a farmer clears

land for farming and then abandons the land

This pond shows what?What will eventually happen to this pond?What is the layer of soil in the bottom of the pond called?

Diversity…• Diversity means differences.• Diversity in populations allows them to be

able to overcome bad things, like viruses and bacterial infections.

• This is true for both plants and animals.• Think of the bubonic plague. How did

humanity survive?• What would happen to us if there was no

diversity and an outbreak of a deadly virus occurred?

Predation

• When an animals stalks, kills and eats another animal, it is called a

• Predator• The animal that is eaten is called the • Prey• What kind of relationship is this?• Predator-prey relationship

Ecology…• Any relationship in which two organisms live

closely together is called a • Symbiotic relationship.• There are three types: mutualism,

commensalism and parasitism

Mutualism

• A relationship in which both species benefit is a• Mutualistic relationship.• Examples:– Cleaning stations: ex: cleaner wrasse and grouper – Bee/flower– Sea anemone/clown fish– Acacia tree/ant– Aphids/ant– cattle egret / large herbivore

The Cleaner Wrasse and an eel

Commensalism

• A relationship in which one organism benefits and the other is neither helped nor harmed is

• Commensalism.• Examples:– Barnacles / whale– Remora / shark– sea star / worm– bromeliads / tree

Parasitism

• A relationship in which one organism benefits and the other is harmed in some way is called

• Parasitism• Examples:– Mistletoe / tree– dog/ tick– bot fly larvae / squirrel– worms / animals

Tropical Rain Forest…

Tropical Rain Forest Facts…• Rains just about every day• Always hot and steamy• No grass on forest floor b/c of thick canopy• Terrestrial biome with the most diversity• Located near equator• Another name is jungle• Lots of vines climbing trees, plants have large

broad leaves so they can collect as much sunlight as possible.

Tropical Savannah or grassland

• Hot year round• Has wet and dry seasons• Compact soil due to enormous herds of large

herbivores• Has frequent fires during dry season

Desert…• Driest biome - • Animals in the desert must be able to tolerate

extreme differences in temperature.• It is extremely hot in the day and cold at night

because of the lack of moisture • Has plants and animals that have adaptations

that allow them to live with very small amounts of water.

• Ex: Ruby!!! Remember, Ruby gets water from the food she eats. (Fennec Fox)

• The desert is home to many species of reptiles, however, there are NO amphibians. Why?

Mojave Desert

• Arizona, California, New Mexico and Nevada• Each of these states have huge populations of

people.• What natural resource is the most scarce in

this part of America?• water

Temperate Forest• We live in the temperate forest.• There are many different kind of mammal

species living in the temperate forest.• Why would an animal NEED to be nocturnal?• Because it is very hot during the day.• Think of deer in our biome during June, July

and August….when are they active? Why?• Think of an opossum… nocturnal…. Short,

stocky body….short ears….prehensile tail

Temperate Forest

Tundra…• Characterized by permafrost which is a layer of

subsoil that is permanently frozen, even in summer.

• Permafrost is the reason there are no trees in the tundra.

• Summers are very short and the temperature is mild.

• During summer months, the sun never sets. • Winters are bitterly cold.• Animals must have adaptations that allow them

to survive in extreme cold.

Temperate Grassland

• Great Plains• Frequent fires• Many large herbivores like buffalo (bison), elk

and deer• Warm summers and cold winters

Cells….• The smallest unit of structure and function in

living things is a • Cell• The thin, flexible membrane surrounding both

plant and animal cells is the • Plasma membrane• The tough, ridged, nonliving outer wall

surrounding plant cells is called the• Cell wall• Proteins are made by the • ribosomes

Cells• A prokaryote has NO nucleus and NO membrane

bound organelles.• Example: Bacteria• A eukaryote has a nucleus and membrane bound

organelles.• Ex: plants, animals, fungi and protists• Levels of organization:Cells tissuesorgans organ systems organism

• Three main parts of all cells: cell membrane, cytoplasm and genetic material (DNA).

• Storage compartments: stores water, salts, carbs and proteins…

• Vacuole• The transport system of the cell is the • ER or endoplasmic reticulum.• A specialized storage compartment found in single celled

eukaryotes that collects excess water and quickly squeezes to expel the water from the body of the single celled organism…

• Contractile vacuole• The control center of the cell is the • Nucleus• Site of photosynthesis• Chloroplast• The cell membrane is made of a double layer of • Phospholipids.

• What does this picture show?

• phospholipids

• Which cell organelle is the garbage disposal of the cell?

• Lysosome• What are two structures used for movement

of single-celled organisms?• Cilia and flagella• Name two structures plant cells have that animal cells do not have.• Cell wall and chloroplast

• Which organelle provides ENERGY for muscle movement and every other process in our body?

• Mitochondria• What is the ENERGY molecule?• ATP – adenosine triphosphate

• The process by which any substance moves from an area of high concentration to low concentration is called

• Diffusion• The process by which WATER moves through a semi-permeable

membrane is called• Osmosis• 23. hypotonic• 24. hypertonic• The only type of movement through the membrane that requires

energy is • Active transport b/c active transport moves a substance AGAINST its

concentration gradient.• Endocytosis and phagocytosis are types of active transport that move

large materials into the cell.• Exocytosis is active transport that pushes materials out of the cell.• All forms of active transport require energy in the form of • ATP!!!! (adenosine triphosphate)

Photosynthesis…• What is this molecule?• Where do the bonds need to be broken to

release energy? b/w 2nd and 3rd phosphate• Energy is released from ATP when a phosphate

group is removed.

Photosynthesis

Photosynthesis• The equation is:

6CO2 + 6H2O + light C6H12O6 + 6O2

• Reactants are: carbon dioxide, water and light• Products are: sugar and oxygen• Photosynthesis occurs in the chloroplast of plant cells.• What are tiny pores or holes in the leaves of plants that allow the

plant cells to obtain CO2 for photosynthesis and the release of O2?• Stomata – they allow GAS EXCHANGE

• Turn to page 219. Let’s look at questions 9 and 10.

Aerobic Respiration

Aerobic Respiration

• Aerobic respiration is another word for• Cellular respiration• In aerobic respiration, one molecule of glucose is

used to produce 36 molecules of ATP.• The equation for aerobic respiration is:6O2 + C6H12O6 6CO2 + 6H2O + ENERGY

Anaerobic Respiration• Also called • Fermentation• Two kinds• Alcoholic fermentation is a process where YEAST

produce alcohol, because there is NO oxygen present.

• Alcoholic fermentation is the process used by YEAST to produce beer, wine, and whiskey. Used in making BREAD!!

• Lactic acid fermentation occurs in muscles of our body – also used to make cheese and yogurt

The Cell Cycle

Phases of Mitosis…

• Prophase:– Longest phase of mitosis– Chromatin condenses into short rod-like structures

called chromosomes.– Nuclear membrane breaks down– Nucleolus disappears

Phases of Mitosis…