Lab Exam 1 Flashcards
(130 cards)
1
Q
define compound microscope
A
uses multiple lenses
2
Q
how do you calculate total magnification
A
multiplying objective lens magnification and ocular lens magnification
3
Q
define eyepiece reticle
A
scale projected over the image to estimate the size
4
Q
define resolution
A
shortest resolvable distance between two objects under the microscope
5
Q
which lens is responsible for most of the magnification and resolution of the microscope
A
objective lenses
6
Q
what parts of the microscope are responsible for producing and shaping the light
A
- light source
- field diaphragm
- aperture
- condenser
7
Q
define science
A
- from latin word meaning knowledge
- covers general truths or the operation of general laws, especially when acquired and tested by the scientific method
8
Q
what is the first step in the scientific process
A
observation
9
Q
define hypothesis
A
suggested explanation for an event which one can test
10
Q
what must a valid hypothesis be
A
- testable
- falsifiable
11
Q
can a hypothesis be proven
A
no
12
Q
define variable
A
any part of an experiment that can vary or change during the experiment
13
Q
define independent variable
A
variable being manipulated or changed
14
Q
define dependent variable
A
variable being measured
15
Q
define control variable
A
variables held constant to not influence outcome
16
Q
define control group
A
- contains every feature of the experimental group except it is not given the manipulation
- ensures results are due to the manipulation
- baseline to compare results
17
Q
steps of the scientific method
A
- observation
- question
- hypothesis
- prediction
- experiment
- analyze results
- support or reject hypothesis
- report results
18
Q
how do termites communicate
A
pheromones
19
Q
characteristics of a compound light miscroscope
A
- uses two sets of lenses
- views thin sections
- illumination from below
- greater magnification than dissecting microscope
20
Q
characteristics of a dissecting microscope/stereoscope
A
- views objects in 3D
- opaque objects viewed with reflected light
- less magnification than compound microscope
21
Q
characteristics of an electron microscope
A
- beam of electrons used
- greater magnification and resolution than light microscopes
- magnification up to 100,000X
22
Q
what is the difference between transmission electron microscopes and scanning electron microscopes
A
- transmission: view thin sections such as cellular organelles
- scanning: view 3D surface of objects
23
Q
what is the most common magnification for the ocular lens
A
10X
24
Q
what are the most common magnifications for the objectives lenses
A
4X, 10X, 40X, 100X
25
what happens to the field of view as you increase magnification
it decreases
26
what happens to the depth of field as you increase magnification
it decreases
27
what are differences between light microscopes, dissecting microscopes, and electron microscopes
- light: use light to produce image, views thin sections, intermediate magnification
- dissecting: use light to produce image, views objects in 3D, lowest magnification
- electron: use beam of electrons to produce image, can view thin sections or 3D surfaces, highest magnification
28
define biomolecules
- large molecules
- necessary for life
- built from smaller organic molecules
29
what are the four major biomolecule classes
- carbohydrates
- lipids
- proteins
- nucleic acids
30
what is the ratio of carbon to hydrogen to oxygen in carbohydrates
1:2:1
31
what are the 3 subtypes of carbohydrates
- monosaccharides
- disaccharides
- polysaccharides
32
what is the most common monosaccharide
glucose
33
how may carbons are in monosachharides
3 to 7
34
how are disaccharides created from monosaccharides
dehydration synthesis
35
what are some common disaccharides
- lactose: glucose and galactose
- maltose: glucose and glucose
- sucrose: glucose and fructose
36
examples of polysaccharides
- starch
- glycogen
- chitin
37
what are the main functions of carbohydrates
- energy
- energy storage
- structure
38
are lipids polar or nonpolar
- nonpolar
- hydrophobic
39
what is the structure of triglycerides
- glycerol
- 3 fatty acids
40
what are the main functions of lipids
- energy storage
- insulation
- metabolize vitamins
- growth and development
- protection
- hormones
- cholesterol
41
what is the most common type of lipid
fats/triglycerides
42
which type of fat is bad and why
- saturated fats
- have only single bonds
- saturated with H
- can pack tightly
- solid at room temperature
43
which macromolecule has the most diverse range of functions
proteins
44
functions of proteins
- enzymes
- transporting molecules
- structure
- hormones
- immune response
- cell adhesion
45
what are proteins made from
amino acids
46
define enzymes
- catalyst in biochemical reactions
- complex protein
- each is specific for a substrate
47
define catabolic enzymes
break down substrates
48
define anabolic enzymes
build more complex molecules from substrates
49
define hormones
- chemical-signaling molecules
- usually small proteins or steroids
- regulate growth, development, metabolism, reproduction
50
what is the most important macromolecule for the continuity of life
nucleic acids
51
functions of nucleic acids
- carry cells genetic blueprint and instructions for functioning
- heredity
52
what are the two main types of nucleic acids
- DNA
- RNA
53
define dehydration synthesis
- how biomolecules are built
- bonds formed through the removal of water
- remove OH from one group and H from another
54
what bonds are formed between monosaccharides after dehydration synthesis
glycosidic bonds
55
what bonds are formed between glycerol and fatty acids after dehydration synthesis
ester linkages
56
what bonds are formed between amino acids after dehydration synthesis
peptide bonds
57
why are the bonds between monomers of biomolecules important
test for presence of bonds to see if a biomolecule is present in a solution
58
benedicts reagent: what does it test for, what is the positive color, what is the negative color
- tests for monosaccharides
- positive: low amount is green, high amount is orange/red
- negative: blue
59
lugol's solution: what does it test for, what is the positive color, what is the negative color
- tests for polysaccharides/starch
- positive: dark blue/black
- negative: orange/brown
60
biruret's test: what does it test for, what is the positive color, what is the negative color
- tests for proteins
- positive: violet
- negative: pale blue
61
sudan IV test: what does it test for, what is the positive color, what is the negative color
- tests for lipids
- positive: red
- negative: clear, dye sinks to bottom
62
which test for biomolecules must be heated
- benedicts reagent
- tests for monosaccharides
63
what is the smallest unit of a living thing
cell
64
what is the level of organization from cell to organism
- cell
- tissue
- organ
- organ system
- organism
65
what are 3 ways we can classify cells
- number: unicellular or multicellular
- photosynthesis ability: plant or animal
- presence of membrane-bound organelles: prokaryote or eukaryote
66
what four things do all cells share (prokaryotic and eukaryotic)
- plasma membrane
- cytoplasm
- DNA
- ribosomes
67
unique features of prokaryotes
- mostly unicellular
- lack nucleus or any other membrane bound organelles
- most have a peptidoglycan cell wall
- many have a polysaccharide capsule
- some have flagella or pili
68
what is the cell theory
- cells are the smallest unit of life
- all living things are made of one or more cells
- all cells come from pre-existing cells
69
function of the plasma membrane
- protects cell
- selectively permeable: allows certain things to enter or exit cell
70
function of the cytoplasm
- surrounds cells internal structures
- where metabolic reactions take place
71
function of nucleus
- holds genetic material (DNA)
- controls cell activities
- nucleolus: produces ribosomes
72
function of ribosomes
- synthesize proteins
73
function of cytoskeleton
- fibers that give support to cell and organelles
- aids in movement
74
functions of mitochondria
- produce energy
- site of cellular respiration
75
functions of vesicles/vacuoles
- storage
- transport
76
functions of lysosomes
- only in animal cells
- digestion and removal of cell waste
77
functions of endoplasmic reticulum
- RER: modifies proteins, synthesizes phospholipids
- SER: synthesizes carbs and lipids, detoxification
78
functions of golgi apparatus
- receives items from endoplasmic reticulum through vesicles
- sorts materials to determine where to send them
79
functions of cell wall
- protection
- maintains cell shape
80
functions of chloroplast
- only in plant cells
- make glucose through photosynthesis
81
functions of cilia and flagella
cell movement
82
unique features of eukaryotes
- have membrane bound organelles
- have nucleus
- have several rod shaped chromosomes
83
define plasma membrane
- phospholipid bilayer with embedded proteins
- controls passage of substances in and out of the cell
84
define diffusion
- passive transport
- substance moves from high to low concentration
85
define osmosis
- movement of water from area of low solute to high solute concentration
86
define hypertonic solution
- higher solute concentration outside of the cell
- water moves out of cell
- cell shrinks
87
define hypotonic solution
- lower solute concentration inside the cell
- water moves into the cell
- cell bursts
88
what is included in cytoplasm
- cytosol
- cytoskeleton
- various chemicals
89
define cytoplasmic streaming
movement of cytoplasm within the cell to transport nutrients, proteins, and organelles throughout the cell
90
which lipid is found within the plasma membrane and affects membrane fluidity
cholesterol
91
what organelles are specific to animal cells
- centrioles/centrosomes
- lysosomes
92
what is the purpose of cell division
- growth
- maintenance and repair of cells
- reproduction for single celled organisms
93
what are the two major phases of the cell cycle (mitosis)
- interphase
- mitotic phase
94
what happens during interphase
- G1: cell growth, protein synthesis, energy reserves
- S: DNA replicated and attached at centromere, centrosomes duplicate and give rise to mitotic spindle
- G2: cell growth, protein synthesis, replenish energy reserves, organelles duplicated, cytoskeleton dismantled
95
what happens during the mitotic phase
- duplicated chromosomes are aligned, separated, and moved to opposite sides of the cell
- cell divided into two identical daughter cells
96
what are the two parts of the mitotic phase
- mitosis
- cytokinesis
97
what happens during mitosis
- 5 stages
- nuclear division
98
what happens during cytokinesis
physical separation of cytoplasmic components into 2 cells
99
what happens during prophase
- nuclear envelope breaks
- centrosomes move to opposite ends of the cell
- spindle fibers emerge from centrosomes
- sister chromatids coil tightly and become visible under microscope
100
what happens during prometaphase
- chromosomes continue to condense
- kinetochores appear at centromeres
- microtubules attach to chromosomes at kinetochore
101
what happens during metaphase
- chromosomes align at metaphase plate
- sister chromatids still attached to each other and spindle fibers
- chromosomes maximally condensed
102
what happens during anaphase
- sister chromatids (now called chromosomes) pulled apart at centromere towards a centrosome
- spindle fibers elongate the cell
103
what happens during telophase
- chromosomes at opposite ends begin to decondense
- mitotic spindles broken down to assemble cytoskeleton
- nuclear envelope begins to form around chromosomes
104
what happens during cytokinesis in animal cells
- contractile ring composed of actin filaments forms at former metaphase plate
- actin filaments pull inward forming a fissure known as the cleavage furrow
- furrow deepens until cell is split
105
what happens during cytokinesis in plant cells
- enzymes, proteins, and glucose move into vesicles during interphase
- vesicles collect at metaphase plate during telophase
- vesicles fuse to form a cell plate
- enzymes use glucose to build new cell wall of cellulose
106
what is the G0 phase
- cells not actively preparing to divide
- some enter temporarily
- some never or rarely divide and remain in G0 permanently (mature cardiac muscle and nerve cells)
107
which phase takes up the majority of the time during the cell cycle
interphase
108
what type of cells does mitosis produce
genetically identical cells
109
what is the purpose of meiosis
to produce haploid gametes for sexual reproduction
110
what happens during prophase 1
- chromosomes seen microscopically
- nuclear envelope breaks down
- homologous chromosomes move towards each other
- synapsis: tight pairing of homologous chromosomes
- crossing over: genes on non-sister chromatids are aligned and segments are exchanged
111
what is the first source of genetic variation produced by mitosis
crossing over in prophase 1
112
what happens during meiosis 2
- connected sister chromatids will split to form 4 haploid cells
- chromosomes are not duplicated
- resembles mitotic division
113
differences between mitosis and meiosis
- mitosis: one division, results in 2 diploid cells that are genetically identical, does not have synapsis or crossing over
- meiosis: two divisions, results in 4 haploid cells that are genetically unique, synapsis and crossing over in prophase 1
114
what are the cells that meiosis makes called
gametes
115
why is meiosis 1 referred to as a reduction division
- number of sets of chromosomes is reduced from 2 to 1
- diploid to haploid
116
define diploid
- cells with 2 copies of DNA
- body cells
117
define haploid
- cell with a single copy of DNA
- gametes (sperm and ovum)
118
who is sometimes referred to as the father of genetics and why
- gregor mendel
- observed traits in peas
- determined individuals have alternate forms of genes called alleles
119
what is the difference between genotype and phenotypes
- genotype: alleles present for each gene; AA
- phenotype: individual's appearance (can be influenced by environment); purple flower
120
define the law of segregation
- genes segregate into gametes so that offspring have an equal likelihood of inheriting either factor
- gametes only carry one allele for a gene
121
define law of independent assortment
- genes do not influence each other during gamete formation
- every combination of alleles is equally likely to occur
122
are dominant traits always more common
- no
- dominant alleles may be rarer in a population
123
what is the phenotypic ratio for offspring from two heterozygous individuals in a dihybrid cross
9:3:3:1
124
what is the phenotypic ratio for offspring from two heterozygous individuals in a monohybrid cross
3:1
125
what antigens are on each blood type
- A: A
- B: B
- AB: A and B
- O: none
126
define codominance
- neither allele is recessive
- both phenotypes are expressed
- red cow mates with white cow and produce red and white spotted cow
127
define incomplete dominance
- two alleles produce intermediate phenotype
- red flower mates with white flower and produce pink flower
128
what happens when chromatids don't separate properly during meiosis 2
- genetic disease
- non disjunction
- ex: down syndrome
129
example of how the envrionment affect phenotypes
- plant has alleles that favor large growth rate
- with good soil and water the plant with grow large
- with poor soil and water the plant will be small
130
is most of out DNA the same or different
the same
