AA

Bio midterm

Biology Midterm Study Guide

Quizlet- https://quizlet.com/996520468/biology-midterm-study-guide-overview-flash-cards/?i=4cqyim&x=1jqt

Freshman year 

Science Practices 

  • How do we build and refine models that describe and explain the natural and designed world?

    • Models help describe and explain Phenomena, such as using diagrams to represent the process of photosynthesis or the structure of DNA. 

  • What constitutes useful scientific evidence?

    • Useful scientific evidence is empirical, reproducible, and supports or refutes hypotheses based on observations and experiments. 

  • How is scientific knowledge constructed? 


  • Knowledge is constructed through systematic investigation, data collection, and analysis, leading to theories and laws. 

  • How does scientific knowledge benefit – deepen and broaden - from scientists sharing and debating ideas and information with peers?

    • Scientists share and debate findings through peer-reviewed journals, conferences, and collaborations, enhancing the depth and reliability of scientific understanding. 

Introduction to Biology 

Safety

  • Always follow lab protocols, wear protective gear, and handle chemicals and equipment responsible to prevent accidents and ensure safety in experiments. 

Scientific method

  •  Steps: Observation → Hypothesis → Experiment → Data Collection → Conclusion

    • Example experiment: testing the effect of light intensity on plant growth

Experimental design

  • Includes independent variable(manipulated variable), dependent variable (measured/ affected variable), and constants(unchanged conditions). 

Independent vs. Dependent Variables

  • Independent Variable

    • The factor changes by the researcher 

      • Light intensity for the previous example experiment 

  • Dependent Variable

    • The measured response that is affected by the independent variable

      • Plant height from the previous example experiment 

How to use measurement and observation tools 

  • Make sure measurements are accurate 

  • Use tools like microscopes, rulers, and thermometers for accurate measurements.

  • Observations should be systematic and recorded for analysis. 

Interpretation of data in tables and graphs

  • Analyze data in tables and graphs to identify trends and relationships. 

    • For example, a line graph could show correlations between temperature and plant color. 

      • Study graphs from Unit One

Characteristics of living things

  • All living things share the following traits 

    •  Made of cells

    • Use Energy

    • Grow and Develop 

    • Reproduce 

    • Respond to Stimuli 

    • Maintain homeostasis 

    • Adapt and evolve 

Core Content Theme: Organization and Development

  • How does structure relate to function in living systems from the organismal to the cellular level?

    • Structure relates to the function of living things from the organismal to the cellular level because even a simple atom has a distinct structure that creates everything that exists. These structures build on top of each other to create larger structures, which eventually create organisms. Therefore, without this complex network, we wouldn't be able to live as successfully or as long as we do, and neither would any other organism. 

Biochemistry 

Atom: Electrons, protons, neutrons, nucleus

  • Atoms are basic units of matter with a nucleus made of protons(positively charged) and neutrons(neutral charge) surrounded by electron clouds(negative charge)

Ions

  • Charged atoms due to electron loss or gain 

Ionic Bonds

  • The transfer of electrons between two unstable atoms (incomplete valence electron shell)

  • Metal x Non-metal  

Covalent Bonds

  • The sharing of electrons between unstable atoms 

Hydrogen Bonding

  • Weak bonds between polar molecules are crucial for water's unique properties. 

Properties of water

  • Cohesion, adhesion, high heat capacity, and solvent properties 

pH: Acids, bases

  • Measures acidity or alkalinity 

    • pH < 7 

      • Acidic

    • pH > 7 

      • Basic

    • pH = 7 

      • Neutral 

Monomers vs. Polymers

  • Monomers are single-units 

    • glucose

  • Polymers are chains of monomers

    • Starch 

Macromolecules

  • Carbohydrates(Polymer)

    • Monomer: Sugar 

    • The carbon is hydrated

      • (literally what carbohydrate means)

    • Made of carbon, hydrogen, and oxygen 

    • There is a functional group but it's not useful

  • Lipids(Polymer)

    • Monomer: Fatty Acid Chain

    • It has a hydrophobic tail(water-hating tail and a Hydrophilic head(water-loving tail)

    • Fatty acids are more often than not attached to a glycerol molecule carboxyloxyl group at the end of the chain. 

      • Attach multiple fatty acid chains to a glycerol molecule 

    • Functional Group: Carboxyl (-COOH) 

  • Proteins(Polymer)

    • Polymer: Amino Acids 

    • Carbon, Hydrogen, Nitrogen, Oxygen and Sulfur

    • Functional Group: Amino (-NH2)& Carboxyl(-COOH)

      • The R-Group is what makes proteins different 

      •  

    • The general structure of an Amino Acid (image above)

    • The side/ R group varies

      •  Can be as simple as hydrogen but can also be more complicated because it determines which of 20 different types of amino acids are formed. 

  • Nucleic Acids (Polymer)

    • Monomer: Nucleotide

    • Carbon, Hydrogen, Nitrogen, Oxygen and Phosphorus

    • Functional Group: Phosphate group

    • All have a phosphate group, five-carbon sugar, and a nitrogenous base(Nitrogen containing base)

    • DNA is made up of Nucleic Acids

    • Nucleotides have three components

      • Phosphate group (P)

      • Pentose (5-C) sugar

        • Sugar can be a Deoxyribose sugar or a ribose sugar (2 variations)

      • Nitrogen-containing base

        • adenine(A), guanine(G),cytosine(C), thymine(T), uracil (U)

          • Adenine bonds with thymine or uracil

          • Cytosine bond with Guanine


Carbohydrates: Monosaccharides, disaccharides, +polysaccharides 

  • Sugars end in -use 

  • Monosaccharide

    • mono- “one” -saccharide “sugar”

    • simple sugar

    • building blocks for complex sugars

      • Example: glucose, fructose, galactose

  • Disaccharide

    • di- “two” -saccharide “sugars”

    • 2 monosaccharides

      • Example:Glucose + Fructose --> Sucrose + H2O

  • Polysaccharide 

    • poly- “many” -saccharide “sugars”

      • This can mean thousands of glucose molecules strung together

    • long sugar chains

    • Examples:

      • Structural 

        • Cellulose

          • The most abundant compound on earth; plants

        • Chitin

          • Exoskeletons of anthropods 

      • Storage 

        • glycogen (animal starch)

        • Starch (Found in plants)

    • Structural use 

      • Helps hold up the plant 

      • Strings of celery are polysaccharides

      • Chitin comprises an exoskeleton 

    • Storage use

      • Store carbohydrates/energy

      • Humans don't have starch

Enzymes: Activation Energy

  • Enzymes lower the activation energy needed for a reaction, allowing it to proceed faster 

Lipids: Glycerol, fatty acids, unsaturated fatty acids vs. saturated fatty acids

  • Fatty Acid

    • glycerol molecule + fatty acid chain 

    • made up of chains of methyl (-CH) units

    • carboxyl group (-COOH) at one end 

  • Lipids are macromolecules but aren't polymers 

    • To make things bigger in a lipid we attach additional fatty acid chains to a glycerol molecule 

  • Saturated 

    • the molecule is saturated with hydrogen; there are no double bonds; the maximum number of hydrogen bonds exists

    • Has to be fully saturated with hydrogens. 

    • There are no bends in the chain

    • Are solids (packed tightly together) 

  • Unsaturated

    • the molecule has at least one double bond meaning there isn’t the maximum number of hydrogen bonds

    • kink/bend in the chain prevents molecules from packing closely together (Are liquids)

    • There is one double bond 

      • Unsaturated stuff is “better” because it is a liquid. 

        • Think of which one you want in your arteries. Solids will clog arteries, liquids will flow freely. 

Saturated

Unsaturated

C-H Bonds 

As many as possible. “Saturated” with hydrogen

One or more double-bonded carbon (C=C) less hydrogen  

Structure

Strai  ght Chain

“Kinked” (bent) Chain 

(C=C bonds)

State at Rm. Temperature 

Solid

Liquids

Example

Animal Fat

Olive Oil

Nucleic Acids (DNA, RNA): Nucleotides

  • Nucleotide

    • nitrogen-containing (nitrogenous) base

    • phosphate group

    • 5-C (pentose) sugar

  • There are two types of nucleic acids 

  • DNA - Deoxyribonucleic Acid

    • Found in the cell’s nucleus

    • These nucleotides have a deoxyribose sugar 

      • Deoxy - 1 less oxygen

    • These nucleotides have the nitrogenous bases of:

      • A, T, C, G 


  

  • RNA

    • Found in the cell's nucleus and cytoplasm

    • Have a ribose sugar 

    • Had the nitrogenous bases of 

    • A, U, G, C 



Cellular Processes

Breakdown, rearrangement, and synthesis of molecules

  • Cellas break down macromolecules for energy or rearrange them for new cellular components 

Dehydration synthesis (Condensation)

  • Known as condensation polymerization

  • It is a type of synthesis reaction

    • A chemical reaction in which smaller molecules join together to make a larger molecule

  • Joins monomers to make polymers 

  • Releases water as a by-product

    • Commonly achieved by combining a hydroxyl (OH) from one monomer and a hydrogen (H) from another monomer to create water. 

Hydrolysis

  • Breaks apart macromolecules(polymers) into monomers by adding a water molecule to break a bond

  • Opposite of dehydration synthesis 

Metabolism

  • The sum of all chemical reactions in an organism

Catabolism

  • Breaking down of molecules 

    • Cellular respiration

Anabolism 

  • Synthesis of molecules 

    • photosynthesis

Homeostasis

Maintenance of optimal conditions

  • Internal factors: organism possess mechanisms to regulate internal conditions such as: 

    • Temperature

      • Through physical and behavioral 

    • pH levels

      • Buffers help maintain a stable pH

    • Water balance

      • Osmosis controls the amount of water that enters and exits a cell

    • Nutrient Levels

      • Digestive processes help regulate nutrient absorption

  • External factors 

    • Temperature and Fluctuations

      • Seasonal changes, weather changes 

    • Water Availability 

      • Drought conditions, access to water 

    • Nutrient Availability

      • Food availability and quality

Cell membrane structure and functions

  • Structure

    • The cell membrane is composed of a phospholipid bilayer with protein, cholesterol, and carbohydrates.

    • Hydrophilic heads & Hydrophobic tails 

    • Protein helps with transport, cell signaling, and cell adhesions.  

    • Cholesterol helps maintain membrane fluidity. 

    • Carbohydrates are involved in cell recognition and communication. 

  • Function

    • Regulates what enters and exits the cell 

    • Maintains the cell's shape 

    • Receives and transmits signals 

    • Allows cells to identify and interact with one another 

Response to changing external environment: tonicity - hypertonic, hypotonic, isotonic

  • Tonicity 

    •  The concentration of solutes( dissolved substances) outside the cell relative to the inside.

  • Hypertonic 

    •  The external solution has a higher solute concentration than the cells' internal environment. 

    • Water moves out of the cell > Cell shrinks 

  • Hypotonic

    • The external solution has a lower solute concentration than the cell’s internal environment.

    • Water moves into the cell > and the cell swells   

  • Isotonic

    • The solute concentration is equal inside and outside of the cell.

    • Water movies in and out at equal rates > size remains the same 

Cell transport

  • Diffusion 

    • The movement of molecules from an area of high concentration to a lower concentration. 

  • Osmosis

    • The diffusion of water across a semi-permeable membrane. 

  • Facilitated DIffusion

    • The transport of molecules across the membrane with the help of protein channels or carriers. 

  • Passive Transport

    •  The movement of substances across the membrane without requiring energy. 

    • This means moving from an area of high concentration to a low concentration.

      • Ex. diffusion, facilitated diffusion, osmosis 

  • Active Transport

    • Movement of substances across their concentration gradient, requiring energy.

    • This means moving from an area of low concentration to an area of high concentration.   

  • Endocytosis

    • The process in which cells engulf materials from the external environment by forming vesicles. 

  • Exocytosis

    • The process by which cells release materials from within by fusing vesicles with the cell membrane. 

 Enzyme function

  • Enzymes

    • Biological catalysts that speed up chemical reactions within cells    

  • Specificity

    •   Enzymes are highly specific, meaning they only catalyze a particular reaction or type of reaction.

  • Active Site

    • The region on the enzymes where the substrate binds

  • Factors Affecting Enzyme Activity 

    • Temperature

      •  Enzymes have an optimal temperature for activity

    • pH

      • Enzymes have an optimal pH range for activity 

    • Substrate concentration

      • Increasing substrate concentration generally increases the reaction rate up to a point

    • Enzyme Concentration

      • Increasing enzyme concentration generally increases the reaction rate

    • Inhibitors 

      • Substances that can reduce or stop enzyme activity 

Organization of Living Things 

Characteristics of living things

  • All living things exhibit the following traits:

    • Organization (cellular and molecular).

    • Growth and development.

    • Energy use.

    • Response to stimuli.

    • Homeostasis.

    • Reproduction.

    • Evolution.

Cell types: Prokaryotic vs. Eukaryotic Cells, Animal vs. Plant Cells

  • Prokaryotic 

    • Smaller 

    • Genetic information is in nucleoid 

    • DNA is circular   

    • Functions take place in the cytoplasm + membrane                                                                                                                                                                                                                                                                                                                                  

  • Eukaryotic 

    •  Larger Nucleus 

    • Nucleus has genetic information

    • Has membrane-bound organelles                                                                                             

  • Animal Cells

    • No cell wall

    • Have ly 

  • Plant cells 

Cell theory

  • All living things/ things that were living contain cells 

  • Cells are the basic units of structure and function in living things 

  • Cells are created from cells 

Cell Structures 

  • Cell/Plasma membrane

    • The plasma membrane separates the cell's internal reactions and structures from the environment and regulates the substance moving in and out of the cell. Plasma membranes (and membranes surrounding many cell organelles) consist of a bi-layer of phospholipid molecules. According to scientific discoveries, the plasma membrane behaves like a thin layer of fluid covering the cell's surface. L

  • Cell wall

    • Most plants are surrounded by a cell wall. The cell wall both protects and supports the cell, The primary walls are made of cellulose and pectin. Other cellulose layers make up the secondary walls. 

  • Cytoplasm/Cytosol

    • The jelly-like fluid that fills the inside of a cell, acts as the medium for most cellular activities by housing organelles, facilitating the movement of molecules within the cell, and providing a space for various metabolic reactions to occur.

  • Nucleus

    • The control center for all cell activity, The nucleus contains hereditary instructions(DNA)and other molecules that function in how the instructions are read, modified, and dispersed.

  • Nucleolus

    • The nucleolus is a thick protoplasm found in the nucleus. It produces and assembles ribosomes.

  • Nuclear Membrane

    • The nuclear membrane separates the nuclear materials from other parts of the cell.

  • Lysosome

    • Lysosomes are rounded organelles that bud from the edges of Golgi bodies. Lysosomes can degrade organelles that are worn out or have served their functions; they can also destroy bacteria and foreign particles, and break down old cell parts.  

  • Chromosomes

    • Chromosomes are long thread-like associations of genes, composed of chromatin. Chromatin chains are clear during the interphase of the cell cycle. Immediately before cell division the individual chromosomes become evident. Chromosomes contain the DNA that codes for proteins.

  • Mitochondria

    • They are membrane organelles that are the center of cellular respiration. The mitochondria carry out the chemical reaction that releases energy stored in carbohydrates to form molecules such as ATP, which provides energy to drive a variety of cellular reactions. 

  • Golgi Apparatus

    •  Carried here by vesicles 

    • Packages and sorts proteins 

  • Rough Endoplasmic Reticulum

    • The rough ER is the same as the smooth ER, except that it is studded with ribosomes. Thus, like the smooth ER, materials can pass through the cytoplasm where they are synthesized and/or “treated” and then sent on their way; because it is studded with ribosomes, those materials are usually protein chains destined for secretion. 

  • Smooth Endoplasmic Reticulum

    • The smooth ER curves through the cytoplasm like interconnected pipelines. These “pipelines” allow materials to pass allow materials to pass through the cytoplasm, where they are synthesized and/or “treated” and then sent on their way. The smooth ER lacks ribosomes and, thus, does not synthesize proteins. However, it is the major site of lipid synthesis in many cells. 

  • Vacuole

    • Vaculoles are membrane structures that serve as storage areas for food, water, or waste. However, the main function of vacuoles is to increase cell size and surface area.

  • Vesicles

    • Carry protein from ER to Golgi and then the final destination

  • Plastid

    • Various types of plastids serve several different functions in plant cells. For instance, leucoplasts are the plastids of plant cells.  

  • Chloroplasts

    • Capture energy from the sunlight and convert it into food that contains chemical energy.

  • Ribosomes

    • Ribosomes are the “workbenches” for protein synthesis; new polypeptide chains, as coded for by DNA, are constructed at their surface. 

  • Microtubules/Microfilaments (Cytoskeleton)

    • Microtubules are straight, hollow rods. The microtubules help to shape and support the cell. 

    • Microfilaments are solid rods. They are known for their part in muscle contraction and help shape and support the cell.   

Matter and Energy Transformations

  • How is matter transferred and energy transferred/transformed in living systems?

    • Matter is transferred/transformed in and out of living systems through biogeochemical cycles such as the carbon, nitrogen, and water cycles. These cycles allow for nutrients to flow through ecosystems starting with producers converting sunlight into chemical energy via photosynthesis, followed by consumers and decomposers transferring and transforming that energy. 

Biosynthesis

Cycling of matter among living and nonliving components

  • The total amount of matter in a system remains constant, even though its form and location change (Law of Conservation of Matter)

Biogeochemical Cycles

  • Nitrogen Cycle

    • Nitrogen is fixed from the atmosphere by bacteria, converted into forms usable by plants (nitrates), and recycled through decomposition and denitrification. 

  • Water Cycle

    • Water cycles through evaporation, condensation, precipitation, runoff, and infiltration into soil and groundwater.

  • Carbon Cycle

    • Carbon moves through photosynthesis (plants take in CO₂ to make glucose), respiration (organisms release CO₂), decomposition (organic matter breaks down), and combustion (burning fossil fuels releases CO₂).

Energy Flow

Food webs are limited 

  • Food Chains

    •  The linear flow of energy from producers to consumers 

  • Food Webs

    • Complex networks of interconnected food chains 

  • Biomagnification/Bioaccumulation

Pyramidal relationships exist

  • Pyramids of Numbers

    • Represents the number of organisms in each trophic level 

  • Pyramids of Biomass

    • Depicts the mass of organisms at each trophic level. 

  • Pyramids of Energy

    • Shows energy transfer, with only about 10% passed to the next level.

Calculating energy transfer: Law of 10’s 

  • Only ten percent of energy travels between each tropic level  

All matter tends toward more disorganized states (entropy), and living systems require a continuous input of energy to maintain their chemical and physical organizations. 

  • First Law of Thermodynamics

    • Energy can not be created or destroyed 

  • Second Law of Thermodynamics

    • The total entropy of an isolated system can never decrease over time.

Photosynthesis 

Photosynthesis Equation

Cellular respiration Equation


Release of Chemical Energy

  • Photosynthesis and cellular respiration are connected. Photosynthesis produces glucose, which is then used by cellular respiration to release energy. This energy is used by cells to power their activities, such as growth, movement, and reproduction. 

Interdependence

  • How are Organisms dependent on Each other? 

    • Organisms are dependent on each other in many ways. For example, plants provide food for animals, and animals pollinate plants. Plants also produce oxygen, which is essential for animal life. Animals decompose dead plants and animals, which return nutrients to the soil. Overall, organisms depend on each other to keep a healthy and functioning ecosystem. 

Populations and Communities 

Limiting Factors

  • A factor that controls the growth of a population

  • Density-dependent factors

    •  Factors that have a greater effect as population density increases 

      • Ex. competition, predation, disease

  • Density-independent factors

    • Factors that affect all populations regardless of their density 

      • Ex. natural disasters, weather events

Abiotic vs. Biotic

  • Abiotic factors

    • Non-living components of an ecosystem 

      • Ex.sunlight, temperature, water, soil

  • Biotic factors

    • Living components of an ecosystem 

      • Ex.plants, animals, fungi, bacteria

Range of Tolerance

  • The range of environmental conditions within which a species can survive and reproduce

    • Temperature tolerance

      • Species have upper and lower temperature limits.

    • Salinity tolerance

      • Organisms have a range of salt concentrations they can tolerate.

    • pH tolerance

      • Species can survive within a specific pH range. 

Niche vs. Habitat

  • Niche

    •  An organism's role in its environment, including how it uses resources, interacts with other species and contributes to the ecosystem.

      • (its "profession") 

  • Habitat

    • The general place where an organism lives 

      • (its "address"). 

Ecosystem Stability

Competition

  • The struggle between organisms for the same limited resources 

    • Ex. food, water, space, mates

  • Intraspecific competition 

    • Competition between individuals of the same species.

  • Interspecific competition

    • Competition between individuals of different species.

  • Competitive Exclusion Principle

    • No two species can occupy the same niche in the same habitat at the same time. One species will eventually outcompete the other.

Predation: Predator, Prey

  • Predation will increase with populated

  • Predators and prey have a strong influence on each other

  • Predators  and prey depend on each other for an increase or decrease in population

    • There is however a lag in growth 

  • Continuous predator-prey dynamics

Symbiotic relationships

  • Commensalism

    • One species benefits and the other is unaffected 

      • Barnacle on a whale 

  • Mutualism

    • Both species benefit 

      • Pees pollinating flowers 

  • Parasitism

    • One species benefits at the expense of  the other

      • Parasite on a Host

Population Density, Dispersion, Distribution

Population Growth Patterns

  • Emigration

    • When individuals move away from a population 

  • Immigration

    • When individuals increase a population  from elsewhere 

  • Mortality

    •  Death rate 

  • Natality

    • Birth rate 

  • Exponential

    • Occurs a population has no limits to its growth

    • Population increases rapidly 

      • J - shaped curve 

  • Logistic (S-shaped curve)

    • Occurs when there is a limiting factor 

    • It starts as a J-shaped curve 

    • Something in the environment becomes limiting

    • Population fluctuates  at carrying  capacity 

      • Called ecological overshoot

      • Going above what the ecosystem can support

  • Factors that impact population growth 

  • Age structure of a population 

    • Developed

      • he birth rate falls to  meet the death rate

    • Developing

      • The death rate begins to fall, but birth rates remain high for a time T

    • Underdeveloped nations

      • The birth rate and death rate are equally high 

Biodiversity

  • The variety of life on Earth, including the genetic diversity within species, the variety of species, and the variety of ecosystems. 

Stable Ecosystems 

  • Characteristics 

    • High biodiversity 

    • Complex food webs 

    • Efficient nutrient cycling 

    • Ability to resist and recover from disturbances 

Succession

  • A predictable way a community can change over time 

  • Determined by the type of disturbance or if soil was left behind 

  • Primary Succession

    • No remnants of an older community 

      • No soil left 

    • Caused by

      • Volcanic Eruptions 

      • Glacier Melting

    • Soil has to be made

    • It occurs in all biomes 

      • Deciduous Forests

      • Grasslands 

      • Aquatic Environments 

      • Tropical Rainforest  

    • Bare Rock > Oppurtunist/Pioneer Species > Simple plants > More Complex Structures 

      • Pioneer Species have few requirements 

        • The first species to colonize bare areas 

        • The start of life

      • As each level passes they add a layer of soil

  • Secondary Succession

    • Soil is present 

    • Disturbance caused by a Natural disaster or Human-caused

      • Buildings 

      • Mowing lawn 

      • Floods 

      • Earthquakes 

  • Pioneer species are commonly simpler plants than  species like Lichens 

  • Climax Community

    • Thought of as a specific, uniform, and stable community the “end“ of Succession

      • That is not always true because Climax Communities aren't always stable  

Biomes: Climatic influence

  • Biomes: large terrestrial ecosystems categorized by specific climate conditions. (temperature and precipitation

    • Types of Biomes:

      • Tropical Rainforest 

      • Tropical Dry Forest

      • Tropical Grassland/Savanna/Scrubland

      • Desert

      • Temperate Grassland

      • Temperate Woodland and Shrubland

      • Temperate Forest

      • Northwestern Coniferous Forest

      • Boreal Forest/Taiga

      • Tundra

      • Polar Regions

  • Climatic Influence: Climate is a major determinant of the types of plants and animals that can survive in a particular biome. 

    • Ex. 

    • Tropical  Rainforest: High temp + heavy year-round rainfall 

    • Desert: High temp + low rainfall 

    • Tundra: Cold temp + low precipitation

Impact of technology and anthropogenic changes to local and global environment and the dynamics of populations

  • Harvesting

    • Over-harvesting of resources can lead to population declines, habitat destruction, and ecosystem disruption. 

      • Ex.overfishing, deforestation 

  • Pollution

    • Air pollution

      • Climate Change, Acid Rain, Respiratory problems 

    • Water Pollution

      • Contaminated drinking water, harms aquatic life 

    • Soil Pollution

      • Degrades soil fertility and harms plant growth  

  • Atmospheric changes

    • Climate changes 

      • Caused by the release of greenhouse gasses from human activities  

        • Such as carbon dioxide and methane 

    • Impacts 

      • Rising global temperatures

      • Changes in precipitation patterns 

      • More frequent and severe weather events 

  • Natural disasters(hurricanes, floods, volcanoes)

    • Some human activities can increase the impact of certain natural disasters

      • Ex. Deforestation can increase the risk of landslides 

Heredity and Reproduction

  • How is Genetic information passed through Generations?

    • Genetic information is passed through generations using DNA, the genetic material that carries the instructions for the development and functioning of all living organisms. 

Genomes

  • The complete set of genetic material found in an organisms 

  • Understanding an organism's genome provides insights into its evolution, development, and disease susceptibility 

DNA Structure and Relationship to Function

  • Structure

    •  DNA is a double-stranded helix, composed of nucleotides. 

  • Base Pairing

    •  Adenine pairs with thymine, and Guanine pairs with cytosine. 

  • Function

    • DNA stores the genetic information necessary for the development and functioning of all living organisms. It acts as a template for the synthesis of RNA, which in turn directs protein synthesis.