Biology

EOCT Review

Types of CellsProkaryotic – no nucleus Eukaryotic – have a nucleus

Types of CellsCell membrane- security fence (protects the cell by controlling what enters and exits the cell)Nucleus-control centerRibosomes-make proteinsGolgi- post office (packages proteins for storage or secretion)Lysosomes- clean-up crew (eat stuff in the cell that needs disposed of)Mitochondria- power house (makes energy for the cell)Vacuoles- storage Cell Organelles (only in plants)Cell wall- protection and support for the plant cellChloroplasts- capture energy from the sun and convert it to chemical energy through photosynthesis

Movement in and out of the cell

• Diffusion• Osmosis• Facilitated Diffusion• Active Transport

Diffusion• movement of particles

from an area of high concentration to an area of low concentration

• Does not require energy• Diffusion stops when

concentration on both sides equal (if crossing a membrane) or when there is a uniform distribution of particles

Osmosis- the passive transport of water

• Osmosis = the diffusion of water across a semi-permeable membrane

• Plasma membrane permeable to water but not to solute – Solute = dissolved particle – Solvent = liquid medium in which particles may be dissolved

• Water moves from solution with lower concentration of dissolved particles to solution with higher concentration of dissolved particles

• Water moves from dilute solution to concentrated solution

Solution types relative to the cell• Hypertonic Solution: Solute

concentration higher than cell – More dissolved particles outside of cell

than inside of cell – Hyper = more – Water moves out of cell into solution – Cell shrinks

• Hypotonic Solution: Solute concentration lower than cell – Less dissolved particles outside of cell

than inside of cell – Hypo = less– Water moves into cell from solution – Cell expands (and may burst)

• Isotonic Solution: Solute concentration equal to that of cell – No net water movement

Facilitated Diffusion

• Allows diffusion of large, membrane insoluble compounds such as sugars and amino acids

• Does not require energy (passive) • Highly Selective • Substance binds to membrane-spanning

transport protein

Active Transport-Movement across membrane against concentration or electrochemical gradient -Movement from low to high concentrations -Used to pump specific compounds in or out of the cell -Requires energy to overcome the concentration and electrochemical gradient

Cell Energy

Photosynthesis – occurs in chloroplast Respiration – occurs in the mitochondria

Respiration Photosynthesis

Reaction type Exothermic – get energy out Endothermic – put energy in

Energy Source Glucose Sun (light)

Form of energy produced ATP glucose

Reactants Oxygen and glucose Carbon dioxide, water, and energy

Products Carbon dioxide and water Oxygen and glucose

Cell ChemistryBuilding blocks Uses Examples

Carbohydrates monosaccharide Quick energy for the body

Glucose, table sugar, corn, bread

Lipids Fatty acids and glycerol

Stored energy for the body

Cooking oil, shortening, bacon grease

Proteins Amino acids Used for growth, repair, and enzymes

Meat and cheese

Nucleic Acids nucleotides Contain genetic information

DNA and RNA

Enzymes

• Enzymes are proteins that work as a catalyst. A catalyst is a substance that increases the rate of a reaction, but does not participate in the reaction

DNA vs. RNA• DNA

– Double stranded– Contains genetic

information needed to make proteins

– Base pairs: Adenine-Thymine; Guanine-Cytosine

• RNA– Single stranded– Makes proteins– Base Pairs: Adenine-Uracil;

Guanine-Cytosine

Protein Synthesis

•Transcription- messenger RNA (mRNA) copies the DNA in the nucleus and carries it out to the cytoplasm•Translation-occurs on the ribosomes, transfer RNA (tRNA) brings the nucleotides to the ribosome so the correct protein can be made

DNA Replication• DNA strand is broken and

each single strand serves as a template to be copied to make a new double strand– Mutations- changes in the

genetic material caused by incorrect copying of the strand during replication

– Examples: Insertions, Deletions, Substitutions

– Mutagenic factors – outside influences that cause DNA mutations

Cellular Reproduction (Mitosis vs. Meiosis)

Meiosis MitosisFunction Sexual reproduction Asexual reproductiongenetically different sameproduces Four haploid daughter cells Two diploid daughter cellsChromosome number Reduced by 1/2 Remains the sameCreates Sex cells All other cells (somatic cells)

Function Sexual reproduction Cellular (asexual) Reproduction (cell division during which the cell nucleus divides); general growth and repair of the body

Occurs in Humans, plants, and animals All organisms

Divisions 2 1

Genetic Terms to know• Allele-gene • Dominant- trait that is seen over others; written as a capital letter• Recessive- trait that is not seen with a dominant trait, but will

appear if it is paired with another recessive trait; written as a lower case letter

• Incomplete or blended dominance- neither gene is dominant • Homozygous- alleles are the same; example: TT or tt• Heterozygous-alleles are different; example: Tt • Phenotype-expression of a trait; example: TT means the individual

is tall• Genotype-genes that make up a trait; example tt

Monohybrid Cross-punnett square is used to show a parental cross of one trait

• Example: Being able to roll your tongue is a dominant trait. If a woman is homozygous dominant for this trait and marries a man that is heterozygous for this trait, what is the possible genotypes and phenotypes of their children?

Tongue Rolling Monohybrid Cross

T T

T TT TT

t Tt Tt

• 100 % will be able to roll their tongue

• 50% homozygous for tongue rolling

• 50% heterozygous for tongue rolling.

Classification• identification, naming, and grouping of organisms into a formal system

based on similarities such as internal and external anatomy, physiological functions, genetic makeup, or evolutionary history.

• The following system is used to classify organisms:– Kingdom, Phylum, Class, Order, Family, Genus, Species

• Example: Domestic dog would be classified as follows• Kingdom: Animalia• Phylum: Chordata• Subphylum: Vertebrata• Class: Mammalia• Order: Carnivora• Suborder: Caniformia• Family: Canidae• Genus: Canis• Species: Canis lupus

– notice the name of a species is given by its genus and species

Six Kingdoms

• Archaebacteria• Eubacteria• Protists• Fungi• Plants• Animals

Archaebacteria

• unicellular bacteria found in extreme environments; prokaryotic; no nucleus; do not use oxygen

Eubacteria

• Unicellular; found in many places; prokaryotic; no nucleus; use oxygen

Protists

• unicellular or multicellular; can be plant-like, animal-like, or fungus-like; do not have true leaves, stems, or roots

Fungi

• unicellular or multicellular; can not move; often decomposers

Plants

• multicellular; cannot move; use photosynthesis to make oxygen; have true leaves, roots, and stems

Animals

• multicellular; consumers (heterotrophs); can move; use oxygen

Characteristics of Life

1. Living Things are Composed of Cells 2. Living Things Have Different Levels of Organization3. Living Things Use Energy4. Living Things Respond To Their Environment 5. Living Things Grow 6. Living Things Reproduce7. Living Things Adapt To Their Environment* Viruses are not considered living things because they

cannot meet these criteria without being attached to another living thing.

EcologyOrganization• Organism- individual member of a species

– Ex: deer• Population- group of the same species in a specific area (habitat) and plays a particular role

(niche)– Ex: # of deer in Stephens County

• Community- interaction of several different populations in an area– Ex: deer along with rabbits, oak trees, squirrels, etc.

• Ecosystem- all living (biotic) and nonliving (abiotic) factors in an area– Ex: the whole forest– *formed by succession.– * Succession is a slow process that changes the species that inhabit an area– Ex) A plowed field eventually turns into a forest

• Biome- Large areas on the earth that contain similar climate, plants, or animals– Ex: Temperate forest

• Biosphere- any part of the earth that sustains life– Ex: Earth

Symbiosis - Relationships between species in an ecosystem

Types of Symbiosis

• Mutualism -both species benefit • Commensalism - one species benefits, the

other is unaffected • Parasitism- one species benefits, the other is

harmed • Competition - neither species benefits • Neutralism - both species are unaffected

Biomes

• Tundra• Taiga• Deciduous forest• Grassland• Desert• Tropical Forest

Tundra• Climate

– Cold• Plants

– No trees, grasses, low shrubs

• Animals– Polar bear– Caribou– Mountain goats

• Movie Example– Rudolph

Taiga

• Climate– Cold

• Plants– Evergreens

• Animals– Moose– Elk– Grizzly bear

• Movie Example

Deciduous Forest

• Climate– Four distinct seasons

• Plants– Hardwoods

• Animals– Squirrel– Deer– Coyote

• Movie Example– Bambi

Grasslands• Climate

– Moderate climate– Unevenly distributed

rainfall• Plants

– Grasses• Animals

– Buffalo– Antelope

• Movie Example– Lion King

Desert• Climate

– Dry• Plants

– Sparse– Cacti

• Animals– Mostly nocturnal– Snakes– Lizards

• Movie Example– Aladdin

Tropical Rain Forest• Climate

– Warm and rainy• Plants

– Large trees– Vines

• Animals– Elephant– Tiger– Chimpanzee

• Movie Example– Jungle Book

• Trophic Levels– Primary producers (organisms that make their

own food from sunlight are the base of every food chain - these organisms are called autotrophs.

– Primary consumers are animals that eat primary producers; they are also called herbivores (plant-eaters).

– Secondary consumers eat primary consumers. They are carnivores (meat-eaters) and omnivores (animals that eat both animals and plants).

– Tertiary consumers eat secondary consumers. – Quaternary consumers eat tertiary consumers.

• Food Chains- sequence of who eats whom in an ecosystem, each level of the food chain is known as a trophic level. As you move up the food chain or pyramid the biomass and energy at that level decreases.

Example of Food Chain

Example of a food Web

Carbon Cycle• Plants use photosynthesis to

change carbon dioxide into glucose and oxygen.

• Animals use oxygen to complete respiration. In this process they return CO2 to the air. Some CO2 returns back to the earth when animals die and are fossilized (fossil fuels). CO2 is released when these fossil fuels are burned.

Water Cycle• Water is moved from the

atmosphere to the earth and back to the atmosphere.

• Rain hits the earth and runs or seeps into streams, lakes, and oceans. The sun heats this water up and causes it to turn into water vapor. It then rises in the atmosphere where it turns into clouds. As it cools, it turns back into rain (precipitation).

Nitrogen Cycle• Nitrogen must pass through this cycle

so it can be used by plants• Nitrogen makes up 79% of Earth's

atmosphere, but most organisms cannot use nitrogen gas (N2). N2 enters the trophic system through a process called nitrogen fixation. Bacteria found on the roots of some plants can fix N2 to organic molecules, making proteins. Again, animals get their nitrogen by eating plants. Animals release nitrogen as a waste product. When they do this, some is used by bacteria through assimilation to convert it to proteins and some is released back as nitrogen gas through denitrification.

Theory of Evolution• Charles Darwin- considered the Father of Modern Evolution• Evolution- is the change in a species over time. However, it is not

a single organism that changes but the genetic material of the species that changes over time.

• Fossil records have provided information on organisms’ evolutionary change.

• Microevolution- Evolution that occurs within the species level. It results from genetic variation and natural selection within a population of organisms.

• Macroevolution- is evolution that occurs between different species. It focuses on how groups of organisms change (i.e., the splitting of a species into two species).

Mechanisms of evolution• natural selection- is the process by which organisms that are

best suited to their environment survive and pass their genetic traits on to their offspring. Adaptation is a key concept in natural selection. Natural selection can change the inherited characteristics in a population and possibly even result in a new species.

• Environment and variations- natural variations within a population allows for some individuals to survive over others in a changing environment. This natural variation sometimes leads to the formation of a new species (speciation). Gene flow- change in the occurrence of genes in a population. Gene flow occurs when an individual leaves a population (emigration) or enters a population (immigration). Mutations- random changes in DNA. Mutations that benefit a species lead to furthering that species instead of the original one. Genetic Drift- provides random changes in the occurrences of genes through random chance events like natural disasters, disease, or starvation. A large population is reduced to only a few individuals. Interbreeding between a small number of individuals causes the genes of subsequent generations to be very similar.

Patterns of EvolutionConvergent Evolution- explains how unrelated species develop similar characteristics

Divergent Evolution- suggests that many species develop from a common ancestor

Types of Behavior

• Innate- genetically control and inherited Animal examples: migration, territoriality, courting, hibernating Plant example: tropisms (growth of a plant in response to a stimulus)

• Learned- a result of experience example: you touch a hot pan and it burns you, you don’t touch it again