biology
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Biology. EOCT Review. Types of Cells. Prokaryotic – no nucleus. Eukaryotic – have a nucleus. Types of Cells. Cell membrane - security fence (protects the cell by controlling what enters and exits the cell) Nucleus -control center Ribosomes -make proteins - PowerPoint PPT PresentationTRANSCRIPT
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