Biology I midterm study guide
Chapter 1
1. Recognize the importance of homeostasis for all living things.
a. Homeostasis is the maintenance of internal conditions near a set point. For example,
your body temperature is kept near 37⁰C, and hormones like insulin and glucagon keep
blood sugar concentrations relatively constant.
2. Understand and apply the scientific method.
a. Be able to distinguish and explain:
i. Observation
ii. Hypothesis
iii. Data
iv. Theory
v. Law
b. Identify the components of a controlled experiment:
i. Control
ii. Independent variable
iii. Dependent variable
Chapter 2
3. Know that all matter is made of atoms, and that elements are particular kinds of atoms.
a. Identify protons and neutrons as being the subatomic particles in the nucleus, and as
the particles that give atoms mass.
b. Distinguish between elements and compounds.
i. Compounds are made of at least two different elements chemically bonded
together.
c. Explain how ions form and how ions make ionic bonds.
i. Negative ions form when a nonmetal element gains one or more electrons.
ii. Positive ions form when a metal element loses one or more electrons.
iii. Ionic bonds form when there is a transfer of electrons from metals to
nonmetals.
d. Explain how covalent bonds between elements make molecules.
i. A covalent bond is the sharing of electrons between two nonmetal elements.
4. Describe hydrogen bonds between water molecules.
a. Why is the oxygen side partially negative?
b. Why is the hydrogen side partially positive?
5. Name and give examples of the 4 properties of water
a. Adhesion
b. Cohesion
c. High specific heat
d. Universal solvent
6. Be able to distinguish solution, solvent, and solute
a. Describe the solubility of covalent, ionic, and polar compounds
7. Relate acids and bases to the pH scale.
a. Acids generate H+ ions in solution and have a low pH number.
b. Bases generate OH- ions in solution and have a high pH number.
8. Know the four macromolecules, their monomers and polymers, and give examples of their jobs
in a cell.
a. Carbohydrates
b. Lipids
c. Proteins
d. Nucleic acids
9. Identify the reactants and products in a chemical equation
a. Be able to identify and distinguish exothermic and endothermic reactions
b. Identify and explain activation energy
c. Explain the effect of a catalyst on activation energy and the rate of a reaction.
d. Describe an enzyme and what enzymes do in cells.
Chapter 3
10. Know the 3 parts of cell theory
a. All organisms are made of cells
b. All existing cells are produced by other living cells
c. The cell is the basic unit of structure and function
11. Define prokaryotes and eukaryotes by the presence or absence of a nucleus
a. Give examples of prokaryotic and eukaryotic organisms
b. Describe the relative size of cells, organelles, and macromolecules
12. Know the cell organelles and their jobs in a cell
a. Cytoskeleton
b. Nucleus
c. Endoplasmic reticulum
d. Ribosome
e. Golgi apparatus
f. Vesicle
g. Mitochondrion
h. Vacuole
i. Lysosome
j. Centriole
k. Cell wall
l. Chloroplast
13. Describe the cell membrane
a. Phospholipids have polar heads and nonpolar tails
b. Describe the orientation of phospholipids in the membrane
c. Describe the movement of membrane proteins in terms of the fluid mosaic model
14. Define selective permeability
a. Locate receptors in the cytoplasm and in the membrane
b. Explain how the chemical properties of a ligand determine the location of its receptor
15. Identify diffusion and osmosis as types of passive transport
a. Diffusion is the movement of a solute from high to low concentration
i. Facilitated diffusion is how polar and charged molecules can diffuse through a
transport protein in the membrane.
b. Osmosis is the diffusion of water from high to low concentration
c. Be able to recognize and use the terms hypertonic, isotonic, and hypotonic.
d. Describe a concentration gradient
16. Describe the three types of active transport
a. Molecular transport (for polar molecules and ions)
b. Endocytosis
c. Exocytosis
17. Distinguish active transport from passive transport
a. Active transport moves up a concentration gradient with an input of energy
b. Passive transport moves down a concentration gradient without energy
Chapter 4
18. Identify ATP as the molecule that stores chemical energy in cells
a. ATP = adenosine triphosphate
i. Adenine + ribose + 3 phosphate molecules
b. ATP releases energy when one of the phosphates breaks away, and the molecule
becomes ADP (adenosine diphosphate).
19. Identify chloroplasts as the organelle that carries out photosynthesis in plants
a. Know that a chlorophyll molecule is much, much smaller than a chloroplast organelle
b. Know that chlorophyll absorb most light wavelengths, except for green light
c. Chlorophyll are located in the thylakoid membranes in the stroma of chloroplasts
20. Be able identify the reactants and products in the chemical equation for photosynthesis
a. Reactants are water and carbon dioxide
b. Products are glucose and oxygen gas
c. Identify carbon dioxide gas as being the carbon source for the production of sugars.
21. Distinguish the light-dependent and light independent reactions
a. Describe where they take place
b. Distinguish their reactants and products
i. Describe how active and passive transport move protons in photosystems II and
I.
ii. Describe how the electrochemical proton gradient causes ATP synthase to make
ATP.
22. Describe the Calvin cycle
a. Identify the reactants
b. Identify the products
c. How many cycles are required to turn 6 carbon dioxide gas molecules into glucose?
23. Compare and contrast cellular respiration to photosynthesis
a. Define aerobic and anaerobic
i. Explain why cellular respiration is aerobic, and why fermentation is anaerobic
b. Explain the role of glycolysis in cellular metabolism
c. Identify the reactants and products of respiration
d. Identify the reactants and products of the Krebs cycle and the electron transport chain.
i. Explain how the electrochemical gradient of protons in the mitochondrial matrix
drives the production of ATP by ATP synthase
ii. Explain why the Krebs cycle depends on the availability of oxygen even though
oxygen is not among its reactants or products
e. Describe how cellular respiration and photosynthesis are opposites
f. Describe how the Krebs cycle and the Calvin cycle are similar and different
24. Describe the role of fermentation in cellular metabolism
a. Distinguish lactic acid and alcoholic fermentation
i. Give examples of organisms that do either process
b. Identify the reactants and products of lactic acid and alcoholic fermentation
c. Connect glycolysis to fermentation
i. Fermentation provides more empty electron carriers to glycolysis, which are
required to produce ATP anaerobically
d. Give examples of the commercial importance of fermentation
Chapter 5
25. Describe the stages of the cell cycle
a. G1
b. S
c. G2
d. M
i. Explain which cells might enter a G0 phase.
26. Explain the difference between mitosis and cytokinesis
a. Mitosis is the division of the nucleus
b. Cytokinesis is the division of the cytoplasm
27. Be able to describe what is happening during the 4 phases of mitosis:
a. Prophase
b. Metaphase
c. Anaphase
d. Telophase
i. Know that interphase is NOT a stage of mitosis
28. Be able to count chromosomes, chromatids, and identify the number of each in a diagram of
mitosis.
a. Know the hierarchy of DNA organization in chromosomes
i. DNA double helix
ii. Histones
iii. Chromatin
iv. Supercoiled DNA
v. Chromatid
29. Explain the important of surface area to volume ratio for cells
a. Be able to calculate cell volume and cell surface area
b. Describe how surface area to volume ratio changes as cells grow and divide
30. Explain how the cell cycle is regulated
a. Describe growth factors and what they cause cells to do
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32.
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b. Explain how apoptosis is necessary for normal development
c. Describe cancer cells
d. Describe the following:
i. Benign tumors
ii. Malignant tumors
iii. Metastasis
iv. Carcinogen
Identify binary fission as the way in which prokaryotes reproduce asexually
a. Know that some eukaryotes also reproduce asexually with mitosis
b. Describe the differences between binary fission and the eukaryotic M-phase.
Know the hierarchy of organization in multicellular eukaryotes:
a. Cells, tissues, organs, and organ systems
Describe the importance of stem cells and differentiation for the process of development
a. Define totipotent, pluripotent, and multipotent stem cells
b. Describe a blastula and the location of pluripotent stem cells
Be able to identify and weigh the ethical complications of extracting pluripotent stem cells
from human embryos.
a. Be able to distinguish arguments that are for or against embryonic stem cell extraction.
Chapter 6
35. Distinguish body cells from germ cells
a. Know that germ cells are not bacteria
b. Know that germ cells are located in the testes of human males, and in the ovaries of
human females.
c. Germ cells produce haploid gametes
36. Explain the difference between autosomes and sex chromosomes
a. Know the difference between homologous chromosomes and sister chromatid
b. Identify homologous chromosomes as making an organism diploid
37. Be able to identify and describe the stages of meiosis
a. Tetrad formation and crossing-over occur in prophase I
b. Cells become haploid after homologous chromosomes segregate in telophase I and
cytokinesis
c. Know that DNA is replicated before the cell begins meiosis I
d. Recognize that meiosis II produces four genetically distinct haploid cells
38. Describe Mendel’s laws of inheritance
a. Law of segregation
b. Law of independent assortment
i. Connect the law of independent assortment to metaphase I.
39. Know the difference between the following terms
a. Dominant
b. Recessive
c. Homozygous
d. Heterozygous
e. Genotype
f. Phenotype
40. Explain Mendel’s breeding experiments
a. Describe the P, F1, and F2 generations
b. Know the Mendelian ratio of dihybrid cross
c. Describe a test cross
d. Be able to calculate the results of a monohybrid cross with a Punnett square
e. Be able to calculate the results of a dihybrid cross
41. Know and use the basic laws of probability
a. Sum rule
b. Product rule
42. Predict the results of a breeding experiment with linked genes
a. Which of Mendel’s laws might not always hold true?
b. Describe how crossing over can make it appear that linked genes are not really linked.