Semester Exam Study Guide 2017 Biology 1 Semester Exam Study Guide 2017

The first 17 slides on this study guide focus on scientific investigation. You will have 25 questions where you will either analyze data in a chart or analyze an experiment. Know the parts of scientific investigation and choose answers based on the information presented in the experiments or figures.

Control groups are needed in order to determine the effect of changing variables in an experiment. There should be 2 groups in an experiment: experimental and control

An inference is a conclusion based on evidence. When looking at a diagram, use the evidence given to make a conclusion.

Scientific observations are made using the 5 senses.

When studying habits or behaviors of organisms, direct observations are the most accurate means of collecting data.

A hypothesis is a possible explanation of an observation that can be tested.

When making a hypothesis based on information in a chart or graph, make sure the hypothesis supports the data in the chart.

All organisms come from parent organisms All organisms come from parent organisms. They do not form from spontaneous generation which is the idea that life can come from inanimate objects.

When using the scientific method, the next step after observation is to form a hypothesis.

In an experiment, the independent variable is the variable that is changed by the person doing the experiment. The dependent variable is the variable that is measured.

Parts of an experiment: Independent variable ( only one ) Dependent variable Constants ( all variable except for the independent and dependent ). A control group that receives no treatment.

A good experiment should have a control group in order to have something to compare experimental data to.

A change of the independent variable in an experiment will result in a change of the dependent variable.

A variable that is analyzed in an experiment should be related to observations made before the experiment and the hypothesis being tested.

The variable that is manipulated and tested in an experiment is the independent variable.

In an experiment, all variables must remain constant except for the independent and dependent variables.

An optimal variable will provide the best or most favorable outcome.

Organisms that have favorable traits are more likely to survive changes in the environment.

Ionic bonds form from the transfer of electrons between atoms.

The ability to dissolve many substances is a property of pure water.

Proteins can form tissues, serve as catalysts, and make up antibodies.

Water is both cohesive and adhesive Water is both cohesive and adhesive. This property allows some insects to stand on the surface of water.

Lipids are macromolecules found in animal tissue that functions in insulation.

Enzymes regulate most cellular activities.

Lipids and carbohydrates are important in cells because both store energy.

Enzymes act as catalysts that drive chemical reactions forward.

Carbohydrates are a source of energy. They are responsible for the production of ATP in cells.

Enzymes only work with specific substrates because they have a specific activation site for enzyme attachment.

Enzymes lower the energy of activation for a reaction.

Overheating can denature an enzyme which will cause it to lose its ability to catalyze a reaction. Changes in pH can also denature an enzyme.

Enzymes can catalyze only one specific type of reaction.

Photosynthesis and cellular respiration exist in a cycle. This means that the products of one reaction are needed as reaction in the other reaction.

Carotenoids are photosynthetic pigments in plants that absorb green light but reflect red, orange, and yellow. Chlorophyll is a photosynthetic pigment that reflects green light.

Oxygen is required for aerobic cellular respiration.

Algae and multicellular plants are autotrophs because they capture sunlight to produce sugars.

Photosynthesis occurs in the chloroplasts of plants. The reactants for photosynthesis: CO2 & H2O The products of photosynthesis: Glucose (C6H12O6) & O2

The energy transferring molecule used by cells is ATP

Cellular respiration occurs in the mitochondria of cells. During this process, carbohydrates are converted in ATP

Proteins are a very diverse group of macromolecules because the different amino acids that can form the proteins can be connected in many different sequences.

According to the cell theory, new cells are produced by the division of existing cells.

The fact that new cells are produced from the division of existing cells was essential to the concept that all life forms have cells as basic units.

Prokaryotes are different from eukaryotes in that prokaryotic cells do not have membrane bound organelles.

The endoplasmic reticulum is an organelle found in eukaryotic cells. The endoplasmic reticulum can be rough or smooth. The rough appearance is due to ribosomes on the surface.

Another difference between prokaryotic and eukaryotic cells is that eukaryotic cells have a more advanced cellular organization.

The main structural difference between eukaryotic and prokaryotic cells is that prokaryotic cells lack a nucleus and membrane bound organelles.

The flagellum is the cellular organelle that is associated with movement of the cell.

The ribosomes are the cellular organelles where protein synthesis occurs. Proteins are formed by amino acids which are held together by peptide bonds.

The golgi bodies are the cellular organelles that package proteins into forms the cell can use, store, or expel.

The cell membrane is the cellular structure that allows the cell to recognize substances in the outside environment.

The vacuole is the cellular organelle that functions in the storage of water, wastes, and food.

Chloroplasts and cell walls are two structures that plant cells have that animal cells do not.

The cytoplasm is the region of the cell that contains the greatest amount of water.

The fluid mosaic model represents the structure of the cell membrane. The function of the cell membrane is to control the passage of materials into and out of the cell.

The main reason the eating salty foods makes a person thirsty is that additional fluid is needed to maintain the fluid balance in cells.

When there is a lower concentration of water outside of a cell rather than inside the cell, the cell will tend to lose water. This is due to the movement of water from high to low concentration.

Protein channels are found scattered throughout the cell membrane. The function of the protein channels is to allow certain substances to enter or leave the cell.

During cellular respiration, the largest amount of ATP is produced by the electron transport chain. 32 ATP are produced during this stage.

The 4 phases of mitosis in order: Prophase: chromosomes become visible Metaphase: chromosomes line up Anaphase: chromosomes are pulled to opposite ends of the cell Telophase: Cell is divided

The processes of meiosis and fertilization help ensure the survival of a species by providing each generation with the same number of chromosomes.

Phases of Mitosis

One strand of DNA could be as long as a football field if it were stretched out. DNA is able to fit inside the nucleus of a cell because of its ability to coil tightly around associated proteins.

Gametes or sex cells must be haploid because 2 gametes will unite during fertilization to create a diploid cell.

During meiosis, homologous chromosomes can exchange DNA is a process called crossing over.

The processes of spermatogenesis and oogenesis are responsible for producing gametes or sex cells with half of the original number of chromosomes.

Hydrogen bonds are responsible for holding water molecules together. Then form between the negative charge of the oxygen and positive charge of the hydrogen.

All cells in an organism have the same DNA. Cells look and function differently from each other because cell specialization is determined by gene expression.

Meiosis only occurs in 2 organs in the body: Testes (male) Ovaries (female)

Sexual reproduction results in greater diversity among offspring than asexual reproduction because of new combinations of genes.

Chromosomal Mutations

The process of DNA replication is necessary before a cell can divide into 2 new cells.

Proteins are formed by monomers called amino acids.

Genetic information is unique to each person because of the sequence of DNA nucleotides in cells.

Tissue samples taken from different structures in the body would have the same DNA. Differences in cell structure would be a result of different genes being expressed.

DNA / RNA Base Pairing DNA RNA

mRNA is responsible for carrying coded information from the nucleus to the ribosomes for protein synthesis.

The process of transferring genetic information from DNA to mRNA is called transcription.

DNA Base Pairing

The weakness of hydrogen bonds between bases of DNA allows base pairs to separate during replication and transcription.

DNA fingerprints are used for identification. Matching base sequences are used to identify relationships.

Scientists classifying animals are most likely to compare the sequence of the animal’s DNA

The chances of developing certain disorders are higher if a family member also has the disorder if they are genetically based.

Medicines are being produced using recombinant DNA technology. The use of this type of technology will result in making more treatments available for medical conditions.

Recombinant DNA is formed by bringing together genetic material from multiple sources. A bacteria plasmid is a commonly used host because of the simple structure.

The process of transcription (DNA to mRNA) occurs in the nucleus. The process of translation (mRNA to protein) occurs in the cytoplasm at ribosomes.