1. Honors Midterm Study Guide
2015

2. Chapter 1

3. 1. Biology—the science of life.
Chapter 1
The Study of Life
1.1 Introduction to Biology
1. Biology—the science of life.
Study the origins and history of life and once-living things
Study the structures of living things
Study how living things interact with one another
Study how living things function

4. 2. An organism is anything that has or once
had all the characteristics of life.

5. The Study of Life
3. The Eight Characteristics of Life
All living things are made of one or more cells. The cell is the basic unit of life.
Living things display organization, which means they are arranged in an orderly way.
Grows and Develops
Reproduces

6. e. Responds to stimuli; The cause of the reaction is the stimulus
e. Responds to stimuli; The cause of the reaction is the stimulus. The reaction to the stimulus is the response.
f. Requires energy
g. Maintains homeostasis; Homeostasis is the regulation of an organism’s internal environment to maintain life .

7. that results from changes to a species over time.
The Study of Life
Adaptations evolve over time; An adaptation is any inherited characteristic
that results from changes to a species over time.

8. The Study of Life
4. Science is the study of nature. The purpose for science is to explain the nature of things.
5. A theory is an explanation of a natural phenomenon supported by many observations and experiments over time.

9. The Study of Life
6. Peer review is a process by which the procedures used during an experiment and the results are evaluated by other scientists who are in the same field or who are conducting similar research.
7. Scientists use the metric system which is based on the powers of ten.This system is called the International System of Units, or SI.

10. 8. The control group in an experiment is a group for comparison
8. The control group in an experiment is a group for comparison. The experimental group is the group exposed to the factor being tested.

11. The Study of Life
Experimental Design
9. The factor that is changed in an experiment is the independent variable. Only one factor in a controlled experiment can change at a time. As a result of this change, the dependent variable is the one measuring the effect of the change.

12. The Study of Life
Data Gathering
Data is gathered quantitatively and qualitatively. Quantitative data can be measurements of time, temperature, length, mass, area, volume, density, or other factors. Qualitative data are descriptions of what our senses detect.

13. The Study of Life
Ask a Question
11. Scientific inquiry begins with observation. Science inquiry involves asking questions and processing information from a variety of reliable sources. This is followed by making logical conclusions called inferences.

14. 12. Steps of Scientific Method - observe, form a hypothesis, experiment, gather and analyze data and draw conclusions.

15. 13. A hypothesis is a testable explanation of a situation.
The Study of Life
Form a Hypothesis
13. A hypothesis is a testable explanation of a situation.

16. Chapter 6

17. Chemistry in Biology
Atoms
14. Atoms are the building blocks of matter. Neutrons and protons are located in the nucleus. Protons are positively charged. Neutrons are particles that have no charge. Electrons are in outer energy level and have a negative charge. The first energy level holds 2 electrons. The second energy level holds 8 electrons.

18. Chemistry in Biology
Compounds
A compound is formed when two or more different elements combine. An example of a chemical formula is H2O.
The total number of atoms in a molecule can be calculated by counting the numbers of each element represented—C6H12O atoms

19. when electrons are shared. A molecule is formed.
Chemistry in Biology
Bonds
17. Ionic bonds form when two oppositely charged atoms are attracted to each other and electrons are transferred. Covalent bonds form
when electrons are shared. A molecule is formed.

20. Oil is a nonpolar compound.
Chemistry in Biology
Water’s Polarity
18. Polarity is the property of having two opposite poles. Water is a polar compound.
Oil is a nonpolar compound.

21. Acidic solutions have pH values lower than 7.
Chemistry in Biology
19. Substances that release hydrogen ions (H+) when dissolved in water are called acids.
Acidic solutions have pH values lower than 7.
Substances that release hydroxide ions (OH–) when dissolved in water are called bases. Basic solutions have pH values higher than 7.

22. 20. Any compound with carbon in it is an organic compound.
Chemistry in Biology
Organic Chemistry
20. Any compound with carbon in it is an organic compound.
Carbon has four electrons in its outermost energy level.

23. 21. The four major categories of macromolecules are carbohydrates, lipids, proteins, and nucleic acids. Organisms use carbs as their main source of energy. Examples of lipids are oils, waxes, and steroids. Proteins are made of amino acids. The two nucleic acids are DNA and RNA.

24. Chemistry in Biology
22. A chemical reaction is a process that changes one set of chemicals into another set of chemicals. Evidence for chemical reaction: production of heat or light, and formation of a gas, liquid, or solid.
Chemical reaction
Physical reaction

25. 23. The activation energy is the minimum amount of energy needed to get a reaction started. An exothermic reaction releases energy in the form of heat . An endothermic absorbs heat energy.

26. Chemistry in Biology
Enzymes
24. A catalyst is a substance that speeds up the rate of a chemical reaction. Enzymes are biological catalysts.

27. Chapter 7

28. 25. Microscopes were first used to look at small organisms.
26. Cell theory states
All living organisms are composed of 1 or more cells.
Cells are the basic unit of structure & organization of all living organisms
Cells come only from pre-existing cells

29. 27. Both eukaryotes and prokaryotes have a plasma membrane and cytoplasm, but eukaryotic cells have specialized structures called organelles that carry out specific cell functions and a nucleus. An example of a prokaryote is bacteria.

30. 28. Animal cells have lysosomes; plant cells have large vacuoles, cell walls, chloroplasts. 29. The plasma membranes maintains homeostasis and is made up of a phospholipid bilayer, in which two layers of phospholipids are arranged tail to tail. It is called the fluid mosaic model.

31. 30. Organelle functions- ribosome – makes proteins ; nucleus – control center of the cell; Rough ER has ribosomes and makes proteins; Smooth ER NO ribosomes and makes lipids; Golgi apparatus modifies, sorts, and packages proteins; Vacuoles store food, enzymes, etc. lysosome – digestive organelle; – cilia and flagella move substances along the surface of the cell; mitochondria powerhouse of cell

32. Cellular Structure and Function
31. Diffusion is the net movement of particles from an area of high concentration to an area of low concentration. Osmosis is the diffusion of water across a selectively permeable membrane.

33. 32. Cells placed in an isotonic solution do NOT change shape because the movement of molecules in and out of the cell is equal. Cells placed in a hypotonic solution swell because there is more water outside the cell than inside the cell. Cells placed in a hypertonic solution shrivel because there is a greater concentration of water inside the cell than outside the cell and water moves out of the cell.

34. 33. Substances move in a cell by passive transport (requires no additional energy) ex. diffusion and facilitated diffusion; active transport requires energy to move substances from a low to high concentration.

35. 34. Transport of large particles is by endocytosis or exocytosis
34. Transport of large particles is by endocytosis or exocytosis. Endocytosis is the process by which a cell surrounds a substance in the outside environment and takes the substance inside the cell. The opposite process, exocytosis, is the secretion of materials at the plasma membrane.

36. Cellular Energy
35. Energy is the ability to do work. Thermodynamics studies the flow and transformation of energy. Law of conservation of energy. This law states that energy can be converted from one form to another, but it cannot be created nor destroyed. The second law of thermodynamics states energy cannot be converted without the loss of usable energy.

37. 36. All energy for life comes from the sun
36. All energy for life comes from the sun. It is the ultimate source of energy for all life. Autotrophs are organisms that make their own food. Heterotrophs are organisms that cannot make their own food and eat autotrophs to get energy.

38. 37. Metabolic pathway - a series of chemical reactions in which the product of one reaction is the substrate (reactant) for the next reaction;
2 types:
anabolic – building up process that uses energy (photosynthesis)
catabolic – breaking down process that releases energy (cellular respiration)

39. Metabolic Pathway Sunlight Photosynthesis (autotrophs)
Cellular Respiration
(heterotrophs)

40. 38. Adenosine triphosphate – ATP is the most important biological molecule that provides energy to the cell. Energy is released when the bond between the 2nd and 3rd phosphate is broken; ADP is formed

41. 39. Plants convert sun’s energy to chemical energy stored in sugar (2 phases) 6CO2 + 6H2O → C6 H12 O6 + 6 O2

42. 40. There are two steps involved in photosynthesis
40. There are two steps involved in photosynthesis. It is called the light dependent reaction(light is required). The light dependent reaction takes place in the thylakoid membranes of the chloroplast. The light dependent phase produces ATP and NADPH which are both used in the 2nd phase of photosynthesis called the light independent phase. Light independent cycle does not require light and occurs in the stroma of the chloroplast.

43. 41. Overview of Cellular Respiration
A process that supplies cells with energy (ATP)
C6H12O6 + 6O2  6CO2 + 6H2O + energy (ATP)
Cellular Respiration takes place in the mitochondria of all eukaryotic cells. There are three main parts in cellular respiration: glycolysis, (anaerobic) Krebs Cycle (aerobic) and electron transport chain(aerobic). Fermentation is a process that produces NAD to allow cells to maintain glycolysis in the absence of oxygen.

44. 42. Lactic acid fermentation occurs when the body cannot supply enough oxygen during exercise. Alcohol fermentation is used in yeast and bacteria.

45. Chapter 9

46. 43. Cells remain small to maximize the ability of diffusion and motor proteins to transport nutrients and waste products because As the cell grows, it’s volume increases more rapidly than the surface area.

47. 44. Chromosomes are made of DNA that carries genetic material 45
44. Chromosomes are made of DNA that carries genetic material 45. Cytokinesis – process that divides the cytoplasm 46. Prokaryotic cells, reproduce by a method called binary fission.

48. 47 .There are three main stages of the cell cycle interphase, mitosis, and cytokinesis. DNA replicates during interphase of cell cycle.

49. The Stages of Mitosis 48. The 4 stages of mitosis are: prophase, metaphase, anaphase and telophase. 49. In prophase, chromatin tightens or condenses into chromosomes. spindle fibers appear and the nucleolus seems to disappear. 50. In metaphase, sister chromatids line up in the middle, or equator of the cell.

50. 51. In anaphase, the sister chromatids are pulled apart. 52
51. In anaphase, the sister chromatids are pulled apart. 52. Two new nuclear membranes begin to form and the nucleoli reappear. 53. Mitosis results in two cells, each with identical nuclei. 54. Cancer is the uncontrolled growth and division of cells--a failure in the regulation of the cell cycle.

51. 55. Cancer cells spend less time in interphase than do normal cells, which means cancer cells grow and divide unrestrained as long as they are supplied with essential nutrients. 56. The one carcinogen no one can totally avoid is the sun.

52. 57. Proteins called cyclins
57. Proteins called cyclins . They regulate the timing of the cell cycle in eukaryotic cells. 58. When an embryo divides, some cells go through a process called apoptosis, or programmed cell death. 59. Stem cells are unspecialized cells that can develop into specialized cells.

53. Chapter 10

54. 60. Mitosis consists of only one set of division phases and produces two identical diploid daughter cells. Meiosis consists of two sets of divisions and produces four haploid daughter cells that are not identical.

55. 61. Stages of Meiosis –Meiosis I a. Interphase -Chromosomes replicate b. Prophase I - Pairing of homologous chromosomes; crossing over c. Metaphase I- homologous chromosomes line up in the middle on equator d. Anaphase I – homologous chromosomes pull apart e. Telophase I - cell divides into two

56. Meiosis II f. Prophase II- sister chromatids recondense in both cells g. Metaphase II – sister chromatids line up on equator h. Anaphase II – sister chromatids pull apart i. Telophase II – four cells develop with unidentical chromatids.

57. 62. A cell with n chromosomes is called a haploid cell
62. A cell with n chromosomes is called a haploid cell. A cell that contains 2n chromosomes is called a diploid cell. Human cells have 46 chromosomes. Gametes have 23 chromosomes.

58. 63. Fertilization - Process by which one haploid gamete combines with another haploid gamete 64. Gametes are formed during a process called meiosis, which is a type of cell division that reduces the number of chromosomes; therefore, it is referred to as reduction division.

59. 65. Meiosis occurs in sex cells. 66
65. Meiosis occurs in sex cells. 66. Monohybrid cross - Crosses that study a single trait; Genotypic ratio 1:2:1; Phenotypic ratio 3:1 67. Dihybrid cross - Crosses that study two or more traits.

60. 68. Law of Independent Assortment states that a random distribution of alleles occurs during gamete formation. This results in the formation of 4 gametes. 69. Mendel’s Law of Segregation states that two alleles for each trait separate independently during meiosis.