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1

Calculate total magnification

4 x 10 = 40
10 x 10 = 100
40 x 10 = 400

2

Describe how to create a wet mount

Take a glass slide

Add a drop of water to a slide and place the specimen in the water (or you may have to place the specimen first and then add the drop of water)

Place the edge of the coverslip on the slide so it touches the edge of the water

Slowly lower the coverslip to prevent the formation and trapping of air bubbles

Remove excess water from the slide using lens paper

3

Biological domains

LOOK AT PAGES 13 and 14 for pictures!

Archaea

Bacteria (Cocci, Bacilli, Spirilla)

Eukarya

4

Eukaryotic kingdoms and an example of an organism in each

LOOK AT PAGES 13-15 for pictures!

Protista - Paramecium, Amoeba, Euglena (active; single-celled; have organelles that can be observed; complex; euglena are easiest to observe; green pigments)

Fungi - Yeast and molds, Penicillium conidia (single-celled and multicelled; grow hyphae, which are long, branching filaments (thread-like) structures)

Plantae - Azolla (multicellular; photosynthetic pigments make easy to see; should not move around; can be seen with naked eye)

Animalae - Rotifers (aka wheel animals), daphnia (aka water fleas); (multi-cellular; complex structure)

5

Hypothesis

-Reflects a tentative answer to a question

-It restates a question with a possible explanation for the observation

6

Control Group

Group that is not exposed to the (independent) variable

7

Experimental Group

Group that is exposed to the (independent) variable

8

Dependent Variable vs. Independent Variable

DV: the outcome you measure (that is meant to be influenced by the IV)

IV: the characteristic you control and manipulate between groups

9

Differentiate the steps of the scientific method and the different approaches demonstrated in lab

Observe → Hypothesize → Test → Interpret

-Used to develop scientific knowledge

10

Biomolecules

Macromolecules (large molecules) found in living systems that contain five or more carbon atoms in either ting or chain formation

-We get MACROmolecules form the food we eat

11

4 key biomolecules essential to life?

Carbohydrates

Lipids

Proteins

Nucleic Acids

12

Organic Compounds

Substances that contain carbon, hydrogen, and oxygen (the 4 key biomolecules are organic compounds)

13

Indicators

Special chemicals that change in some way in the presence of a specific organic substance

14

Triglyceride

-Type of lipid

-Consist of a glycerol molecule combined with three fatty acids

15

Hydrophilic

-Water loving

-Polar molecules that are soluble in water

-Polar molecules tend to have slight differences in electrical charge associated with different parts of their molecular structure; this polarity is caused by unequal sharing of electrons associated with the internal bonds that hold the molecule together

16

Hydrophobic

-Water fearing

-Polar molecules that are not soluble in water

17

Recognize tests and indicators that detect the presence of carbohydrates, lipids, and proteins

-Sudan III

-The Biuret Test

-Benedict’s Reagent

-Iodine

18

The Biuret Test

Detects proteins and peptides

-Positive = Reactant changed from blue to violet color (pinkish-purple) because of amine groups in amino acids reacting with copper ions

-Negative = Blue color

19

Benedict’s Reagent

Detects reducing sugars (carbohydrates)

-Positive = Green (low concentration); Yellow, orange, or red-orange (high concentration)

-Negative = Maintains blue color

20

Iodine

Detects for starches (carbohydrates)

-Positive = Changes from maroon (brownish) to dark blue-black color

-Negative = Maintains brownish color

21

Sudan III

Detects Lipids

-Positive = orange-colored spot on the filter paper

-Negative = indicated by a spot lacking color OR one with red particles

-It’s hydrophobic

-Polar molecules won’t take up this dye

22

Amino Acid

-Basic unit of protein

-Bond between amino acids is called a peptide bonds

23

Monosaccharide

-One-sugar or singular sugar

-Basic building blocks for carbohydrates (simple sugars)

-Ex: glucose and fructose

24

Polysaccharide

-Sugars containing several to many monosaccharides linked together (many-sugars)

-Ex: starch

25

Describe the controls used in the biochemical tests

-The control for all the tests was distilled water (dH2O) because it does not contain any macromolecules

-If control gives you a positive result, test is invalid (because solutions likely to be contaminated)

26

Recognize the typical structures in human cells

-Structure of a typical cell is divided into three major parts:

1) Plasma membrane (cell membrane), which envelops (or encloses) the rest of the cell

2) Cytoplasm, which is comprised of a liquid medium known as cytosol containing the functional subunits called organelles

3) A membrane-bound structure that contains DNA, the nucleus

-Each cell is a membrane-enclosed sac containing smaller subunits that perform cellular function

27

Plasma Membrane

-Structure: lipids and proteins, with some carbohydrates

-Location: Envelopes entire cell

-Primary Functions: Provides selectively-permeable barrier for cell; regulates movement of material in and out of cell

28

Cytoplasm

-Structure: Mixture of water, salts, and organic molecules that form a thick fluid (cytosol) and organized structures (organelles)

-Location: Interior of cell

-Primary Function: Region of cellular metabolism and other activities that maintain the cell

29

Cytosol

-Structure: Thick, gel-like fluid mostly made up of water; also contains salts, protein filaments (making up cytoskeleton), soluble proteins, and other organic molecules

-Location: Interior of cell; surrounds organelles

-Primary Function: Allows transport of substances within cell

30

Centrioles

-Structure: Composed of microtubules forming cylinders (often starburst-like in appearance)

-Location: Near nucleus in the centrosome

-Primary Function: Participates in cell division

31

Cilia

-Structure: Short, slender projections in certain cells

-Location: Extended outward away from cell surface

-Primary Function: Motile cilia are used to propel fluids or small particles

32

Flagella

-Structure: Composed of bundles of fused microtubules

-Location: Tail-like appendage that protrudes through cell membrane to the exterior of the cell

-Primary Function: Movement of cell

33

Ribosomes

-Structure: Very small, spherical structures composed of RNA and protein

-Location: Often attached to the ER or unattached in cytoplasm

-Primary Function: Sites of protein synthesis

34

Rough ER

-Structure: Large, branching, membrane bound structure that may be flatted or tubular

-Location: Extends from nuclear envelope within the cytoplasm

-Primary Function: Sites of protein synthesis

35

Smooth ER

-Structure: Relatively large, membrane bound, branching structure that may be flatted or tubular; studded with ribosomes

-Location: Within cytoplasm

-Primary Function: Site of lipid and carbohydrate assembly

36

Golgi Apparatus

-Structure: Series or stacks of membrane bound, disc-shaped sacs

-Location: Within cytoplasm, usually near the nucleus

-Primary Function: Prepares and packages proteins for transport

37

Mitochondria

-Structure: Spherical or sausage-shaped structures; membrane bound

-Location: Throughout cytoplasm

-Primary Function: Site of cellular respiration where ATP is produced

38

Lysosomes

-Structure: Small, spherical structures; membrane bound

-Location: Throughout cytoplasm

-Primary Function: Contain enzymes that break down waste material and cellular debris

39

Vesicles

-Structure: Small membrane bound sacs

-Location: Throughout cytoplasm, usually near the Golgi apparatus

-Primary Function: Transport of materials within the cell

40

Nucleus

-Structure: Large, often spherical structure surrounded by a double membrane (envelope)

-Location: Often located at the center of the cell

-Primary Function: Contains genetic material which regulates protein synthesis and cell division

41

Nucleolus

-Structure: Small spherical structure containing proteins and nucleic acids

-Location: Within the nucleus

-Primary Function: Site of RNA synthesis (transcription)

42

Nuclear Envelope

-Structure: Double membrane with large pores

-Location: Envelops the nucleolus and nucleoplasm

-Primary Functions: Provides selectively-permeable barrier; regulates movement of material in and out of nucleus

43

Nucleoplasm

-Structure: Gel-like fluid consisting of water, nucleic acids, and proteins

-Location: Contained within the nuclear envelope and surrounds chromosomes and nucleoli

-Primary Function: Contains material associated DNA and RNA synthesis

44

Chromatin

-Structure: Thread-like material composed of DNA and protein

-Location: Throughout nucleoplasm

-Primary Function: Genetic material which controls protein synthesis

45

Red Blood Cells


Specialize to allow space for transport of oxygen and carbon dioxide

46

White Blood Cells

Associated with your defense against disease and infection

47

Mitosis

The sequence of changes that separates the nucleus and the chromosomes (the latter already replicated during S period interphase) into two identical sets

Includes Prophase, Metaphase, Anaphase, Telophase, and Cytokinesis

48

Diploid Cell

“Two”

-Each chromosome has its homologous copy

49

Identify the stages of mitosis

-Interphase
-Prophase
-Metaphase
-Anaphase
-Telophase
-Cytokinesis

50

Interphase

-Distinct nucleus visible

-Two or more nucleoli

-Nuclear envelope intact

-Includes:
G1: Cell grow larger
S: Cell replicate chromosomes
G2: Cell prepare to divide

51

Prophase

-1st step of Mitosis

-Condensing chromosomes become visible

-Spindle fibers appear

-Nuclear envelope disappears

52

Metaphase

-2nd step of Mitosis

-Sister chromatids line up along the equator of the cell

-Spindle fibers are attached to the sister chromatids

53

Anaphase

-3rd step of Mitosis

-Sister chromatids separate (now called chromosomes again) and move towards the opposite poles of the cell

54

Telophase

-4th step of Mitosis

-The chromosomes have reached the opposite poles of the cell

-Spindle fibers disappear

-Nuclear envelope reforms

55

Cytokinesis

-4th (if combined with Telophase) or 5th (if completely separate) step of Mitosis

-Begins while the cell is still in telophase

-A cleavage furrow forms across the middle of the cell, dividing the cytoplasm

-This will develop into the new plasma membrane for each daughter cell

56

Zygote

-Fertilized cell

-Receives half of each homologous pair of chromosomes from maternal source (egg) and half from paternal source (sperm)

57

Understand the process of meiosis and the final result

-Meiosis is specialized type of cell division that starts with a diploid cell, but produces reproductive cells called gametes (either egg or sperm)

-Each gamete has only one chromosome from each of the original homologous chromosome pairs, making them haploid cells

-Final Result: gametes (sex cells) that are haploid (containing only half of DNA homologous pair)

58

Understand the principles of genetic inheritance

-Variations in physical and behavioral characteristics of offspring result from the mixing of genetic information from the maternal and paternal sources

-Genes → Alleles (different versions of genes) → Dominant vs. Recessive → Phenotype and Genotype determined (Homozygous vs. Heterozygous too) → This all leads to what you inherit

59

Be familiar with the genetic traits discussed in lab

-Cleft Chin (it’s dominant)

-PTC Tasting (tasters are dominant)

-Color-blindness (it’s recessive)

-Ear Lobes (unattached is dominant)

-Tongue Rolling (the ability is dominant)

-Mid-digital Hair (Having hair is dominant

-Bent Little Finger (Bending is dominant)

-Interlocking Fingers (Left thumb over right is dominant)

-Hitchhiker's Thumb (Having it is recessive)

60

Genes

-Units of inheritance

-Segment of DNA on a chromosome that determines the physical expression of a trait

61

Alleles

-Alternative forms of a gene

62

Dominant

An allele that completely masks the physical expression of another allele

63

Recessive

The allele not being expressed

64

Genotype

The two alleles that represent a gene

65

Phenotype

The physical expression of the genotype

66

Homozygous

-Genotype where two alleles are the same

-”Homo” = “same”

67

Heterozygous

-Genotype consisting of two different alleles

-”Hetero” = “different”

68

Incomplete Dominance

-The dominant allele does not completely mask the expression of the recessive allele (ex: pink flower thing)

69

Polygenic Inheritance

The trait is influenced by multiple genes, potentially on different chromosomes

70

Understand the structure of DNA and the process of DNA replication

-DNA: Deoxyribonucleic acid; provides genetic blueprint that determines and controls living organisms; large double-stranded, helical molecule contains genetic instructions that direct assembly of protein molecules from simpler molecules

-Structure:
-Spends much of its time as stringy structure, but
-When cells prepare to divide, DNA forms into dense structures called chromosomes
-Composed of small units called nucleotides

-Replication:
-Step 1: An enzyme called a DNA helicase unwinds the DNA strands, separating the weak hydrogen bonds between the nitrogenous bases holding the two strands together
-Step 2: Another enzyme called DNA polymerase then builds a new complementary strand to each of the single “parent” strands
-Step 3: Result is two new DNA molecules each composed of one original parent strand and one newly synthesized strand

-DNA is replicated so that each daughter cell will get an exact copy
-Variety of enzymes and other factors are required for replication

71

Understand transcription and translation

-Transcription: Process of making mRNA; similar to DNA replication; requires a host of enzymes and other factors

-Translation: mRNA fits into a site on ribosome where its message is “read” by tRNA, which moves about the cytosol and acquire amino acids, placing them into the growing chain of amino acids until the protein coded by the mRNA is synthesized and released

72

Understand the differences between DNA, mRNA, and tRNA

DNA: Provides genetic blueprint that determines and controls living organisms

mRNA: Messenger RNA; it’s a copy of DNA; the process of making mRNA is transcription

tRNA: Transfer RNA; another type of RNA; “reads” the messages of mRNA and builds protein with amino acids

73

Understand the mutation that causes sickle cell anemia

It’s a mutations that changes a protein which results in some red blood cells forming sickled shapes (crescent moon shapes) instead of the normal biconcave (more circular) cells

74

Proteins

Structural and functional molecules that carry out most cellular activities, in essence the activities of life, including the synthesis of all other biological molecules

75

Nucleotides

-They compose DNA

-Their sequence code for protein

76

rRNA

-Ribosomal RNA

-Made up of the same nucleotides as mRNA, but instead of carrying the message of DNA, rRNA folds upon itself, creating ribosomes

77

Genetic Code

-In the form of three nucleotide sequences called codons

78

Codon

Three nucleotide sequence

-Each codon identifies a particular amino acid

79

Anticodon

Complementary code to a particular codon

80

Silent Mutations

A mutation that may not affect the protein produced

81

Mutation

An error in DNA

82

How do DNA and RNA vary in function?

DNA provides the genetic blueprint from which RNA synthesizes proteins

83

In what two ways does the chemical makeup of DNA and RNA vary?

DNA is in the nucleus and consists of bases ATCG. RNA is in the cell cytoplasm and consists of bases AUCG

84

What is the function of tRNA?

tRNA recognizes the mRNA sequence and assembles the appropriate amino acids to form a protein

85

Sickle cell anemia is a condition that has sickled blood cells instead of biconcave cells. This condition is a result of _____?

An abnormal protein that is formed by a mutation in the genetic code.