Cell structure/ types Flashcards

1
Q

Mitochondria

A

“cellular power plants” because they generate most of the cell’s supply of adenosine triphosphate (ATP), used as a source of chemical energy via aerobic respiration. They take in O2, and Glucose and expel, CO2 , H2O, and ATP

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2
Q

ATP

A

Adenosine triphosphate: energy within cells for metabolism. It is produced by photophosphorylation and cellular respiration and used by enzymes and structural proteins in many cellular processes

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3
Q

Cytoplasm

A

is the region between the cell membrane and the nucleus. All the contents of the cells of prokaryotic organisms (which lack a cell nucleus) are contained within the cytoplasm

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4
Q

Lysosome

A

(Recycling Center) organelles that contain acid hydrolase enzymes to break down waste materials and cellular debris. They can be described as the stomach of the cell

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5
Q

Smooth Endoplasmic Reticulum

A

is involved in the synthesis of lipids, including oils, and fats (liver/muscle cells) and steroids (ovary/teste cells), and detoxification of drugs and poisons (liver cells)

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6
Q

Ribosome

A

(workbenches) Not an organelle (no membrane) synthesizes protein chains. It assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule. Ribosomes are divided into two subunits. The smaller subunit binds to the mRNA and then the roughER. (some remain ‘free’ and unattached)

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7
Q

Golgi Complex

A

(Distribution Center) receive Transport Vesicles and their modified proteins from RER. They are sorted and addressed, and some further modified. The proteins exit either out of cell, to cell membrane or into cytoplasm.

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8
Q

Transport Vesicle

A

(shuttles) membrane-lined spheres that transport proteins or molecules through cytosol via the microtubules.

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9
Q

Endomembrane System

A

group of membrane-lined organelles and transport vesicles in Eukaryotes

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10
Q

Aerobic Respiration

A

The breakdown of glucose to ATP using Oxygen within mitochondria. Oxygen (breathed in) + Glucose (eaten) = CO2 (exhaled) + Water + ATP (energy)

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11
Q

Free Ribosomes

A

Ribosomes that do not attach to the RER. They synthesize proteins using mRNA/tRNA for use within the cell (usually)

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12
Q

RNA (4 types)

A

mRNA- messenger RNA, transcribe the DNA code for a particular protein in nucleus, exit via pores, enter ribosome.
tRNA- transfer RNA, enter ribosome and match nucleotides with mRNA bonding their attached amino acids to form protein chain.
rRNA- ribosomalRNA used to make Ribosomes
microRNA- small RNA chains that halt translation by binding to the mRNA and cutting it in half

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13
Q

Nucleus (4 parts)

A

Nuclear Envelope: double membrane that confines the DNA and Nucleus
Nucleolus: Center of Nucleus that synthesizes rRNA
Nuclear Pores: Exits from Nucleus
DNA: cookbook of information for assembling proteins.

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14
Q

Flagella

A

Tail-like extensions that function for cell movement. (only animal flagella is sperm cell tail) They are extensions of the microtubules.

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15
Q

Cilia

A

Hair-like growths that move very rapidly for propelling cell, or moving material around cell. Common among single-celled organisms.

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16
Q

Cytoskeleton (3 sizes)

A
  1. Microfilaments: small fibers that reach out for movement or to capture prey. (pseudopodium)
  2. Intermediate Filaments: most stabilizing of cytoskeleton.
  3. Microtubules: largest, determine shape of cell. Act as monorails for organelles movement.
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17
Q

Cytosol

A

Gel-like liquid (mostly water) within the Cytoplasm. The matrix.

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18
Q

Organelle

A

Membrane bound, highly organized internal structure of a cell that performs a specific function. Specific to Eukaryotes

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19
Q

Prokaryotes Characteristics

A
Bacteria and Archaea
DNA not enclosed (naked chromosomes)
Much smaller than Eukaryotes
single-celled
Ribosomes
Cell Wall
Cell Membrane
Flagella (sometimes)
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20
Q

Eukaryotes Characteristics

A
DNA enclosed within a Nucleus (membrane-lined)
Much larger than Prokaryotes
Multi-cellular (mostly)
Compartmentalized
Organelles (many types)
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21
Q

Virus

A

Alive/Not Alive debate
Largest Virus much smaller than smallest bacteria
cannot reproduce without using machinery of other cells

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22
Q

Nucleotides (3 parts)

A
  1. Phosphate Group the rails
  2. Sugar (deoxyribose)
  3. Nitrogen-containing base (4): Adenine(A) , Guanine(G), Cytosine(C), Thymine(T). the rungs
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23
Q

Nucleic Acids

A

DNA and RNA

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24
Q

Plant Cells have….. Animal Cells don’t

A

Cell Walls, Chloroplasts, Central Vacuole

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25
Q

Gap Junctions

A

Communication channels between adjacent cells in animals that open only as necessary.

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26
Q

Centriole

A

Cluster of microtubules that, during mitosis, pull DNA pairs apart to separate cells

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27
Q

channel protein

A

a type of pore in the cell membrane that channels molecules or ions across the membrane through the protein.

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28
Q

carrier protein

A

protein that selectively combine with ion or substance to help it move across the membrane. Think of a key fitting into a lock

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29
Q

fluid-mosaic model

A

a phospholipid bilayer has a fluid consistency similar to oil, allowing lipid molecules the freedom to move. Proteins embedded on the outside or within the bilayer form a mosaic pattern

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30
Q

glycolipids

A

are phopholipids that have attached carbohydrate (sugar) chainsglyco=sugar

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31
Q

glycoproteins

A

have attached carbohydrate (sugar) chainsglyco=sugar

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32
Q

selectively permeable

A

the fluid-mosaic membrane is selectively permeable because some small molecules can pass through the phospholipid bilayer but larger molecules cannot

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33
Q

Active Transport

A

Transport of a substance across a membrane that does not rely on the potential energy of a concentration gradient for the substance being transported and therefore requires and addititonal energy source (often ATP)

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34
Q

Amphipathic Molecule

A

A molecule containing both hydrophobic and hydrophilic regions.

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35
Q

Concentration Gradient

A

A difference in the concentration of a substance from one point to another, as for example, across a cell membrane.

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36
Q

Diffusion

A

The net movement of particles (atoms, molecules, or ions) from a region of higher concentration to a region of lower concentration, resulting from random motion.

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37
Q

Endocytosis

A

The active transport of substances into the cell by the formation of invaginated regions of the plasma membrane that pinch off and become cytoplasmic vesicles.

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38
Q

Exocytosis

A

The active transport of materials out of the cell by fusion of cytoplasmic vesicles with the plasma membrane.

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39
Q

Facilitated Diffusion

A

The passive transport of ions or molecules by a specific carrier protein in a membrane.

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40
Q

Gated Channel

A

Channel proteins that open or close based on the presence or absence of a physical or chemical stimulus.

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41
Q

Hypertonic Solution

A

A term referring to a solution having an osmotic pressure (or solute concentration) greater than that of the solution with which it is compared

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42
Q

Hypotonic Solution

A

A term referring to a solution having an osmotic pressure (or solute concentration) less than that of the solution with which it is compared.

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43
Q

Integral Protein

A

A protein that is tightly associated with the lipid bilayer of a biological membrane.

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44
Q

Isotonic Solutions

A

Solutions that have identical concentrations of solute molecules and hence the same osmotic pressure.

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45
Q

Ligand

A

A molecule that binds to a specific site in a receptor or other protein.

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46
Q

Osmosis

A

The net movement of water by diffusion through a selectively permeable membrane from a region of higher concentration of water to a region of lower concentration of water.

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47
Q

Passive Transport

A

The diffusion of a substance across a biological membrane.

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48
Q

Peripheral Protein

A

A protein associated with one of the surfaces of a biological membrane.

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49
Q

Phagocytosis

A

Literally, “cell eating”; a type of endocytosis by which certain cells engulf food particles, microorganisms, foreign matter, or other cells.

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50
Q

Pinocytosis

A

Cell drinking; a type of endocytosis by which cells engulf and absorb droplets of liquids.

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51
Q

Receptor-Mediated Endocytosis

A

A type of endocytosis in which extracellular molecules become bound to specific receptors on the cell surface and then enter the cytoplasm enclosed in vesicles.

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52
Q

Selective Permeability

A

Allowing some substances to cross more easily than others.

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53
Q

Sodium-Potassium Pump

A

Active transport system that transports sodium ions out of, and potassium ions into, cells.

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54
Q

Transport Protein

A

A protein that helps molecules or ions pass through lipid bilayer membranes.

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55
Q

Define a tissue.

A
  • aggregation of similar cells and intervening extracellular matrix that serve specific function
  • group of similar cells and surrounding extracellular matrix and extracellular fluid (also known as ‘intercellular’)
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56
Q

Name the four main tissue types.

A
  1. epithelia
  2. connective tissue
  3. muscles
  4. nervous tissue
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57
Q

Define organ.

A
  • groups of tissues that are assembled into units that serve broad bodily functions
  • ie: bones, skin
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58
Q

Cells perform these seven general functions (also list the associated cells):

A
  1. Movement (muscle cells)
  2. Conductivity (nerve cells)
  3. Metabolic absorption (kidney and intestinal cells)
  4. Secretion (mucous gland cells)
  5. Excretion (all cells)
  6. Respiration (all cells)
  7. Reproduction (most cells)
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59
Q

What are seven membrane proteins in the cytoplasmic membrane?

A

Channel Proteins

Enzyme Receptors Receptor Sites Identifier Proteins Carrier Proteins

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60
Q

Define: Metabolism

A

The sum of all physical chemical changes that occur in the body.

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61
Q

Define: anabolism

A

The building of larger substances from smaller substances, such as the building of proteins from amino acids.

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62
Q

Define: catabolism

A

The breakdown of larger molecules into smaller ones that the body can use for its own needs.

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63
Q

The three stages of cellular respiration:

A

Glycolysis Krebs (citric acid cycle, tricarboxylic acid cycle)Electron Transport System

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64
Q

Define: oxidation

A

Utilization of glucose by the cell

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65
Q

Cytoplasmic membrane

A

Contains cellular contents; regulates what enters and leaves the cell

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66
Q

Nucleus

A

Contains genetic information; control center of the cell

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67
Q

Protons

A

in nucleus, positive charge

68
Q

Neutrons

A

in nucleus, no charge

69
Q

Electrons

A

orbit nucleus, negative charge

70
Q

1st valence shell

A

holds 2 electrons

71
Q

2nd, 3rd, 4th, etc shells

A

holds up to 8 electrons

72
Q

Chemical bonds

A

formed to stabilize atoms

73
Q

Ions

A

charged atoms

74
Q

Ionic bond

A

bond between 2 ions of opposite charges

75
Q

Hydrogen bond

A

attraction of hydrogen atoms of one molecule to an atom of another molecule; it’s a weak bond

76
Q

Chemical reactions

A

a substance are changed into one or more new substances

77
Q

Synthesis reaction

A

builds, requires energy- A + B –> AB

78
Q

Decomposition reaction

A

breaks apart- AB –> A + B

79
Q

Exchange reaction

A

synthesis & decomposition reactions both involved- AB + CD –> AD + CB

80
Q

Reversible reaction

A

chem bonds can be made and can be broken down- AB A + B

81
Q

Atomic #

A

of protons

82
Q

Atomic mass

A

of protons and neutrons

83
Q

Acid

A

donates hydrogen ions when dissolved in water; proton donator

84
Q

Base

A

donates hydroxide ions when dissolved in water; proton acceptor

85
Q

Salt

A

dissolves into cations & anions when dissolved in water; formed when acids & bases react

86
Q

pH scale 0-14

A

7 on pH scale more hydroxide (OH-) ions, more basic/alkaline

7 on pH scale equal # of OH- and H+ ions, neutral

87
Q

Human blood on pH scale

A

7.35-7.45

88
Q

Interphase

A

cell prepares for mitosis, DNA & chromosomes duplicate

89
Q

Prophase

A

chromosomes condense, nuclear envelope disassembles

90
Q

Metaphase

A

chromosomes align along equator, spindle fibers attach to duplicated chromosomes

91
Q

Anaphase

A

spindle fibers contract to separate duplicated chromosomes

92
Q

Telophase

A

nuclear envelope reforms around 2 groups of identical chromosomes

93
Q

Cytokinesis

A

cytoplasm of one cell is divided into two daughter cells

94
Q

Mitosis

A

division of nucleus and chromosomes- stages: prophase, metaphase, anaphase, telophase

95
Q

Peroxisomes

A

detoxifies harmful substances (alcohol) and breaks down lipids in liver/kidneys

96
Q

Osmosis

A

water molecules diffuse in an attempt to equalize concentration on both sides of membrane

97
Q

Facilitated transport

A

molecules move from area of HIGH TO LOW concentration with help from a transport protein

98
Q

Active transport

A

molecules move from area of LOW TO HIGH concentration against concentration gradient, requires ATP

99
Q

Phagocytosis

A

eating of worn out cells, bacteria, viruses

100
Q

Exocytosis

A

material moved out of cell by being pinched off; membrane sac formed around it & it fuses w/ cell membrane

101
Q

Cellular respiration

A

process of converting food molecules into ATP

102
Q

Aerobic respiration

A

oxidation of molecules in presence of oxygen, in mitochondria; very efficient

103
Q

Anaerobic respiration

A

oxidation of molecules in absence of oxygen, in mitochondria; less efficient

104
Q

Isotonic solution

A

solution outside cell has equal amount of dissolved solutions in cell

105
Q

Inorganic compounds

A

lack carbon, simple structure; dissolve in water

106
Q

Organic compounds

A

always contains carbon and usually hydrogen; dissolve in organic liquids (ie. alcohol)

107
Q

Carbohydrates

A

-function: fuel; -structure: C, H, O, monosaccharides are basic bldg block

108
Q

Monosaccharide

A

one sugar molecule; simple sugars (ie. glucose in blood sugar)

109
Q

Disaccharide

A

two sugar molecules bonded together (ie. glucose + fructose = sucrose aka table sugar)

110
Q

Polysaccharide

A

many sugar molecules bonded together; complex carbs (ie. starches- storage form of sugar in plants)

111
Q

Proteins

A

-function: support, energy source, antibodies, bio catalyst; -structure: C, H, O, N, S, amino acids are bldg blocks; made in ribosomes

112
Q

Amino acids

A

-structure: amino group- NH2, carboxyl group- COOH, hydrogen atom, r-group- gives amino acid unique properties, bonded to central carbon atom

113
Q

Nucleic acids

A

-structure: C, H, O, N, P, bldg blocks are nucleotides; -function: has code for genetic info

114
Q

Nucleotides

A

composed of a 5 carbon sugar (deoxyribose), nitrogenous base, phosphate group;

115
Q

Process inside the nucleus when the DNA code is “copied” as an mRNA molecule forms

A

Transcription

116
Q

Genetic material of he cell that carries the chemical “blueprint” of the body (2 words)

A

Deoxyribonucleic Acid

117
Q

A nucleic acid found in the cytoplasm that is crucial to protein sysnthesis (2 words)

A

Ribonucleic Acid

118
Q

One pair of tiny cylinders in the centrosome of a cell

A

Centriole

119
Q

A beadlike structure that attaches one chromatid to another during the early stages of mitosis

A

Centromere

120
Q

Condition in which cells change in orientation to each other and fail to differentiate into specialized cell type

A

Anaplasia

121
Q

Synthesis of a protein in cytoplasm by ribosomes

A

Translation

122
Q

Amino acids of the nearly 100 found in nature are used to build body protein. Proteins are used in the formation of:

A
Hormones
Enzymes
Plasma proteins
Muscle proteins
Hemoglobin
Most cell membranes
123
Q

Arrange the phases of mitosis in the correct sequence:

A
  1. Interphase 2. Prophase 3. Metaphase 4. Anaphase 5. Telophase
124
Q

Nucleic acids are composed of units called nucleotides that have three parts. The nucleotides for DNA are:

A
Sugar (Deoxyribose)
Phosphate group (PO4)
Bases--
-Adenine (A)
-Thymine (T)
-Cytosine (C)
-Guanine (G)
125
Q

What is the system of bonding known as complementary base pairing?

A

Adenine can only pair with thymine (A-T).

Cytosine can only pair with guanine (C-G)

126
Q

RNA is also a nucleotide that is composed of three parts:

A
Sugar (ribose)
Phosphate group (PO4)
Bases--
-Cytosine (C)
-Guanine (G)
-Adenine (A)
- Uracil (U)
127
Q

DNA directs the function of each protein cell

A

True. In addition to carrying genetic code, DNA also directs the function of cellular proteins

128
Q

What type of division occurs in sex cells?

A

Meiosis

129
Q

In meiosis, how many times does the cell divide, and how many cells do you get from the division(s)?

A

The cell divides twice, leaving you with four new cells.

130
Q

What is the order of stages in meiosis?

A

Interphase, prophase, metaphase, anaphase, telophase, prophase 2, metaphase 2, anaphase 2, telophase 2, cytokinesis.

131
Q

What happens during the interphase stage of both meiosis and mitosis?

A

cell carries on normal functions- growing, respiration, making proteins;2/3 of cell life happens in this stage; DNA (chromatin) and centrioles replicate.

132
Q

What happens during prophase(1)?

A

Chromatin becomes chromosomes (sister chromatids); nucleus disappears; centrioles move to opposite poles; spindle forms (in meiosis crossing over occurs)

133
Q

What parts of the cell are important for cell division ans what is their function?

A

centrioles-Centrioles are involved in the organization of the mitotic spindle and in the completion of cytokinesis. [5] Centrioles were previously thought to be required for the formation of a mitotic spindle in animal cells. However, more recent experiments have demonstrated that cells whose centrioles have been removed via laser ablation can still progress through the G1 stage of interphase before centrioles can be synthesized later in a de novo fashion .[6] Additionally, mutant flies lacking centrioles can develop almost normally, although the adult flies lack flagella and cilia, a lack that underscores the requirement of centrioles for the formation of these organelles Cells whose centrioles have been removed via laser ablation or genetic manipulation lack aster microtubules. These cells often fail to undergo proper asymmetric cell division, as the aster microtubules help to position the spindle within the cell. chromatids- A chromatid is one among the two identical copies of DNA making up a replicated chromosome, which are joined at their centromeres, for the process of cell division (mitosis or meiosis). The term is used so long as the centromeres remain in contact. When they separate (during anaphase of mitosis and anaphase 2 of meiosis), the strands are called sister chromatids. ribosomes-Ribosomes are the workhorses of protein biosynthesis, the process of translating mRNA into protein. The mRNA comprises a series of codons that dictate to the ribosome the sequence of the amino acids needed to make the protein. Using the mRNA as a template, the ribosome traverses each codon (3 nucleotides) of the mRNA, pairing it with the appropriate amino acid provided by a tRNA. Molecules of transfer RNA (tRNA) contain a complementary anticodon on one end and the appropriate amino acid on the other. The small ribosomal subunit, typically bound to a tRNA containing the amino acid methionine, binds to an AUG codon on the mRNA and recruits the large ribosomal subunit. The ribosome then contains three RNA binding sites, designated A, P, and E. The A site binds an aminoacyl-tRNA (a tRNA bound to an amino acid); the P site binds a peptidyl-tRNA (a tRNA bound to the peptide being synthesized); and the E site binds a free tRNA before it exits the ribosome. Protein synthesis begins at a start codon AUG near the 5’ end of the mRNA. mRNA binds to the P site of the ribosome first. The ribosome is able to identify the start codon by use of the Shine-Dalgarno sequence of the mRNA in prokaryotes and Kozak box in eukaryotes

134
Q

How many chromosomes does each cell end up with in meiosis and mitosis?

A

Quantity In humans, for example, there are normally 23 pairs of homologous chromosomes in each cell (N=23). However, the quantity of chromatids will be a multiple of 23. It can be either 4N, 2N or 1N. N does not refer to haploid or diploid; it refers to the number of chromatids in the cell as a multiple of the haploid number of chromosomes for the organism. For example, because a human haploid germ cell has 23 chromosomes, then “N” refers to a multiple of 23. (e.g. 2N=46 chromatids). The last is only seen in haploid gametes, with only one of each homologous chromosome pair. Such are created in gametogenesis. [edit] 4N In a cell with 4N chromatids, there are 23 chromosome pairs (46 chromosomes), and each chromosome has 2 chromatids. Thus, there are 92 chromatids in each cell (4N). It occurs after the S phase of interphase. (See cell cycle). [edit] 2N Immediately after a mitosis, where a cell has divided in two, but not yet duplicated its DNA in S phase, there are still 23 chromosome pairs (46 chromosomes). However, each chromosome only has one chromatid. Thus there are 46 chromatids (2xN) Alternatively, a haploid cell with two chromatids per chromosome also has 46 chromatids. However, this doesn’t occur naturally in human somatic cells. [edit] 1N Immediately after meiosis, each cell, called a gamete, only has half the number of chromosomes (23 chromosomes). Furthermore, each chromosome only has one chromatid. Thus, there are 23 chromatids (1xN)

135
Q

What are the stages of mitosis?

A

interphase, prophase, metaphase, anaphase, telophase, cytokinesis. ( I predict Molly ate two crabs)

136
Q

What does mRNA do?

A

Messenger ribonucleic acid (mRNA) is a molecule of RNA encoding a chemical “blueprint” for a protein product. mRNA is transcribed from a DNA template, and carries coding information to the sites of protein synthesis: the ribosomes. Here, the nucleic acid polymer is translated into a polymer of amino acids: a protein. In mRNA as in DNA, genetic information is encoded in the sequence of nucleotides arranged into codons consisting of three bases each. Each codon encodes for a specific amino acid, except the stop codons that terminate protein synthesis. This process requires two other types of RNA: transfer RNA (tRNA) mediates recognition of the codon and provides the corresponding amino acid, while ribosomal RNA (rRNA) is the central component of the ribosome’s protein manufacturing machinery

137
Q

Cell division for producing gametes (eggs or sperm) is called

A

MEIOSIS

138
Q

Cell division for growth is called

A

MITOSIS

139
Q

Chromosomes are long and string-like when..

A

cells are NOT dividing

140
Q

The first step in either MITOSIS or MEIOSIS is for the long string-like chromosomes to…

A

thicken and shorten

141
Q

How many daughter cells do we get from MITOSIS

A

TWO

142
Q

IN MEIOSIS the daughter cells have __________ the number of chromosomes of the original cell

A

half

143
Q

Which type of cell division is basically ‘cloning’ a cell (making an exact copy)

A

MITOSIS

144
Q

TRUE OR FALSE:

ALL the daughter cells from meiosis will have identical DNA

A

FALSE

145
Q

How many chromosomes does a human body cell have?

A

46

146
Q

How many chromosomes does a human egg cell have?

A

23

147
Q

TRUE OR FALSE:

During BOTH mitosis and meiosis, the chromosomes double and look like ‘x’s

A

TRUE

148
Q

A chromosome is …

A

A structure found inside the nucleus of a cell which carries some of the instructions for the organism. A chromosome has many genes (sections that relate to a specific trait)

149
Q

trait means …

A

characteristic

e.g. hair colour, adult height, type 1 diabetes

150
Q

recessive means …

A

if an allele (form of a gene) is recessive, then BOTH genes must be the same for the trait to be expressed.
e.g., Only bb would code for blue eyes

151
Q

dominant means …

A

if an allele (form of a gene) is dominant, then only ONE copy is needed for the trait to be expressed.
(The other copy of the gene can be the same or different)
e.g., BB OR Bb might code for brown eyes

152
Q

allele means …

A

form of a gene. E.g., blue eyes and brown eyes are two alleles for the gene that codes for eye colour

153
Q

what is a gene?

A

A gene is a part of a chromosome that codes for a specific trait
(e.g. the gene might be the instruction set for an amino-acid chain that may be used in making the pigment in brown eyes)

154
Q

If yellow eyes are dominant and red eyes are recessive, how would a scientist write the genotype for a red-eyed animal?

A

yy

the letter used is by convention/tradition the first letter of the dominant trait

155
Q

If Gray fur is dominant and blue fur is recessive, what colour fur would a creature with the genotype Gg have?

A

Gray fur

156
Q

What is Mm: a genotype or a phenotype?

A

Genotype (genotypes are always represented by letters)

157
Q

Genotype ratio shows the expected fraction or percentage of each ___________ in the offspring of a cross.

A

genotype

158
Q

Homozygous

A

when both of the alleles for a trait are the same

159
Q

Heterozygous

A

when an individual has difference alleles for a trait

160
Q

Phenotype

A

the physical expression of the genotype

161
Q

Pleioptropic genes

A

genes that affect many different characteristics

162
Q

multiple allelism

A

When traits are determined by more than two alleles

163
Q

Polygenic traits

A

Such is the case when more than one gene is responsible for the creation of a trait

164
Q

epistatic traits

A

When a gene interferes with the expression of another, masking the effect.

165
Q

Gene Linkage

A

when two (or more genes) are on the same chromosome and consequently linked