Midterm1 Flashcards
(80 cards)
1
Q
Describe properties of living organisms
A
- Living organisms must be able to grow, metabolize substances, reproduce, and respond to external stimuli.
- Living organisms contain a common set of biological molecules, are composed of cells, and can maintain homeostasis and evolve
2
Q
List the components of water and some of the properties that make it important in living organisms
A
- water consists of 1 oxygen and 2 hydrogen atoms
- Water is a good solvent in part because of its polarity and ability to form hydrogen bonds. Hydrogen bonding in water facilitates chemical reactions, promotes cohesion, and allows fo rheat absorption.
- The polarity of water also facilitates the dissolving of salts
- water has a neutral pH.
3
Q
pH scale
A
measure of the relative percentages of ions in a solution and ranges from 0 (acidic or rich in hydrogen ions) to 14 (basic or rich in hydroxyl ions)
4
Q
describe how structure affects chemical bonding
A
- Chemical bonding depends on an elements electron configuration. Electrons closer to the nucleus have less energy than thos that are farther away from the nucleus.
- Atoms that have space in their valence shell form chemical bonds.
5
Q
hydrogen bond
A
weak attraction between hydrogen atoms and oxygen atoms in adjacent molecules
6
Q
covalent bond
A
bond that forms when atoms share electrons. Tend to be strong bonds
7
Q
Ionic bond
A
bonds formed between positively and negatively charge ions. Tend to be weaker bonds.
8
Q
Importance of Carbon
A
life on earth based on carbon chemistry. the element carbon can bond with up to 4 other elements.
9
Q
carbohydrates
A
function in energy storage and play structural roles. They can be single-unit monosaccharides or multiple unit polysaccharides with sugar monomers joined by covalent bonds
10
Q
proteins
A
play structural, enzymatic, and transport roles in cells. composed of amino acid monomers joined by covalent bonds
11
Q
lipids
A
partially or entirely hydrophobic and come in three forms. Fats are glycerol covalent bond to 3 fatty acids. fats store energy.
12
Q
Phospholipid
A
lipid composed of glycerol, 2 fatty acids, and a phosphate group. important structure component of cell membranes
13
Q
steroid
A
composed of 4 fused rings. Cholesterol is a steroid found in some animal cell membranes. Other steroids act as hormones
14
Q
Nucleic acids
A
polymers of covalently bonded nucleotides, each composed of sugar, a phosphate, and a nitrogen containing base
15
Q
prokaryotic cell
A
cell lacking a membrane bound nucleus
16
Q
eukaryotic cells
A
cells containing membrane bound nucleus
17
Q
mitochondria and chloroplasts
A
energy conversions
18
Q
lysosomes
A
breakdown of macromolecules
19
Q
ribosomes
A
sites for protein synthesis
20
Q
smooth endoplasmic reticulum
A
synthesizes lipids
21
Q
Golgi apparatus
A
sorts proteins and sends them to their cellular destination
22
Q
centrioles
A
help cell divide
23
Q
macromolecules in living organisms
A
carbohydrates, proteins, lipids, and nucleic acids
24
Q
metabolism
A
all of the chemical processes that occur in the cell including breakdown, synthesis and excretion
25
homeostasis
roughly constant internal environment
26
enzymes
proteins that accelerate and help regulate all chemical reactions that build up and break down molecules inside the cell
27
amino acids
monomer subunits of proteins. 20 commonly occurring carbons, hydrogens, oxygens, nitrogen, and side groups
28
nucleotide
sugar, phosphate, nitrogen containing base
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macronutrients
nutrients that are required in large amounts including water, carbohydrates, proteins, and fats
30
passive transports
includes simple diffusion and facilitated diffusion (diffusion through proteins) .
Always moves substance with their concentration gradient and does not require energy.
31
osmosis
diffusion of water across a membrane
32
active transport
active transport is an energy requiring process that requires proteins in cell membranes to move substances against their concentration gradient
33
endocytosis and exocytosis
large molecules move into and out of cells in membrane bound vesicles
34
enzyme
proteins speed up or catalyze the rate of biological reactions
35
substrate
chemicals that are metabolized by an enzyme catalyzed reaction are call the enzymes substrate
36
cellular respiration
series of metabolic reactions that converts the energy stored in chemical bonds of food into energy that cells can use while releasing waste product. glucose + oxygen = carbon dioxide + water
37
glycolysis
in cytesol part of cellular respiration 6 carbon sugar broken into 3 carbon pyruvic acid molecules
38
citric acid cycle
in the mitochondrial membrane. pyruvic acid is decarboxylated. remaining 2 carbon fragment moves to inner matrix of mitochondria and citric acid cycle strips them of carbon diozxid and electrons
39
electron transport chain
after glycolysis and citric acid cycle. electrons are carried by electron carrier (NADH) to inner mitochondrial membrane. added to series of proteins. oxygen pulls electrons toward itself. as electrons move down the chain the energy they release drives protons (H+) into intermembrane space. Once there, protons rush through the enzyme ATP synthase and produce ATP from ADP and phosphate
40
which of the following can neutralize dangerous free radicals within the body
antioxidants
41
what is the cause of 1/3 cancer deaths and 90% of lung cancer
smoking
42
the process by which cells of a malignant tumor can break and start new cancer at a distant location
metastasis
43
tumors that stay in one place and don't affect surrounding tissues
benign
44
which of the following is not a known carcinogen
| *the following are carcinogens
tobacco use, high fat/low fiber diet, lack of exercise, obesity, excess alcohol consumption, and increasing age
45
sister chromatids
replicated copy of chromosomes paired are called sister chromatids. each composed of one dna molecule and attached toward the middle and centromere.
46
DNA polymerase
moves along length of unwound dna helix and helps bind nucleotides to eachother on newly formed daughter strant.
47
mitosis
asexual division that produces daughter nuclei that are exact copies of the parent. happens in somatic cells
48
somatic cell
non sex cell
49
Steps of mitosis division
Interphase, mitosis, cytokinesis
50
Interphase
two phases G1 and G2. g1 organelles duplicate. G2 proteins synthesize to drive mitosis. cell grows and prepares to enter mitosis. S phase is when dna replicates but does not condense (happens between g1andg2) .
51
mitosis phase
prophase: dna condenses into chromosomes, microtubules phorm and anchored by centrioles. nuclear envelope breaks down.
- metaphase:chromosomes ALIGN at the middle of cell between the 2 poles. microtubules grow long enough to attach to centromeres.
- anaphase: Microtubules contract and separate sister chromatids
- telophase: nuclear envelope reforms chromosomes uncondense
52
cytokinesis
filaments band and contract around equator of cell producing two daughter cells to form. Mitosis: two daughter cells 46 chromosomes, meiosis: four daughter cells 23 chromosomes
53
growth factor
protein that stimulate cell to divide
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meiosis
cell division reduces chromosomes to produce gametes with only half the chromosome of further cell. produced in sex organs. through phases g1, s, g2, meiosis1, meiosis2
55
alleles
different versions of the same gene are called alleles of a gene.
56
meiosis 1 phase
prophase1: nuclear envelope breaks down, microtubules begin, dna condenses to chromosome.
- metaphase: homologous chromosomes align at middle of cell in random alignment
- anaphase:homologous chromosomes are separated
- telophase1 and cytokinesis: cell divides produce 2 daughter cells.
- carries on to meiosis 2
57
meiosis 2 phase
- prophase2:microtubules lenthen
- metaphase2:chromosomes align at middle of cell
- anaphase2:sister chromatids separated
- telophase 2 and cytokinesis: four haploid daughter cells result nuclear envelope reforms
58
crossing over
occurs during prophase 1 of meiosis1. portions of chromosomes exchange from one homologous pair to the other member. increases genetic diversity
59
nondisjunction
the failure of chromosomes to seperate
60
trisomy
presence of extra chromosome
61
monosomy
absence of a chromosome
62
genetic variation
process of transmitting genes from one generation to the next with variation among genes
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independent assortment
alleles for each gene are inherited mostly independent of each other
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genotype
the genetic composition of an individual
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phenotype
physical traits of an individual
66
heterozygous
two different alleles for a gene
67
homozygous
two copies of same allele for a gene
68
fig. 8.11 from textbook. what are the chances a hemophiliac male and unaffected female could have a baby that is a hemophiliac male?
none
69
a family tree that is used to follow human matings that have already occured
pedigree
70
incomplete dominance
phenotype of progeny is intermediate to that of both parent
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codominance
both alleles of a given gene are expressed
72
x inactivation
one of 2 x chromosomes in females is inactivated and genes residing on it are not expressed. inactivation passed to all daughter cells.
73
mutation
changes to dna sequences that effect protein structure and function.
neutral mutation changes to dna that do not result in a different amino acid being incorporated. can result in frameshift mutations that change protein drastically
74
gene expression
- given cell only expresses small % of genes organism posseses
- eukaryotic cells one of 5 ways:1 increasing transcription through use of proteins that stimulate RNA polymerase binding, 2. varying time that dna spends in the uncondensed active form, 3. altering mRNA lifespan, 4. slowing down or speeding up translation, 5. affecting protein life span
75
stem cells
undifferentiated cells that can be programmed to act as a variety of cell types. may allow scientists to treat degenerative diseases
76
human genome project
resulted in production of complete DNA sequence of humans
77
gene therapy
replacing defective genes or their products in an embryo or affected adult tissue. gene therapy is experimental but hold promise when scientist learn to target genes to the right location and express them in proper amounts
78
nuclear transfer
used to clone animals with desirable agricultural traits.
79
transcription
copying of dna gene into rna synthesized by rna polymerase.
80
translation
mRNA used to produce protein for which the gene encodes. needs mRNA, amino acids, ATP energy, ribosomes and tRNA
