Introduction to Cells

Question 1

Cell Theory

Answer 1

The cell is the basic organizational unit of life

All organisms are comprised of 1 or more cells

Cells arise from pre-existing cells

Question 2

Prokaryote

Answer 2

No nuclei

Single-celled (can live in chains or communities)

Bacteria and Archaea (live everywhere)

Question 3

Eukaryote

Answer 3

Nuclei (membrane-bound nucleus)

Single-celled (Ex. Yeast) or multicellular

Plants, fungi, animals, humans

Question 4

Origins of Mitochondria (and Chloroplast)

Answer 4

Fossil evidence suggests that prokaryotes arrived/evolved first.

Prokaryotes and eukaryotes share many similar characteristic, thus we believe that they could not have arose separately.

Symbiotic relationship; endosymbiont theory; entangle-engulf-endogenize theory

Note: we do not really know how it happened

Question 5

Ectosymbiont

Answer 5

Live outside of their hosts’ cells

Question 6

Endosymbiont Hypothesis

Answer 6

some of the organelles in eukaryotic cells were once prokaryotic microbes

Question 7

Endosymbiont Hypothesis Support/Proof

Answer 7

Mitochondria and chloroplast have remnants of their own genomes and their genetic systems resemble that of modern-day prokaryotes

Mitochondria and chloroplasts have kept some of their own protein and DNA synthesis components and these resemble prokaryotes too

Membranes in mitochondria and chloroplasts often similar to those in prokaryotes and appear to have been derived from engulfed bacterial ancestors

Question 8

What are the general attributes of Model organisms?

Answer 8

Rapid development with short life cycles

Small adult (reproductive) size

Readily available (collections or wide-spread)

Tractability – Ease of Manipulation or modification

Understandable Genetics

Question 9

Model Organisms

Answer 9

A living thing selected for intensive study as a representative of a large group of species.

Question 10

Central Dogma

Answer 10

Original model for information flow (we now know it is far more complicated that this)

DNA —(transcription)— RNA — (Translation)— Protein

Question 11

DNA

Answer 11

a cells complete set of genetic information is the genome, that includes the mitochondria DNA

The nuclear genome may mean just the nucleus DNA.

Question 12

Trasncriptome

Answer 12

All the RNA present in a cell at a given point in time. Constantly changing (unlike the genome); lets us know the genes of a species and their sequences

Question 13

Proteome

Answer 13

All the proteins in the cell at given time. Changing all the time; the entire set of proteins that is, or can be, expressed by a genome, cell, tissue, or organism at a certain time.

Question 14

Interactome

Answer 14

All the protein-protein interactions in a cell at a given point in time. The set of all molecular interactions in cells, especially in the context of protein-protein interactions; feeds information to the metabolome

Question 15

Metabolome

Answer 15

The set of all the metabolites in a cell at a given times. Effects the genome, transcriptome and Proteome; complete set of low molecular weight compounds in a cell at a given time

Question 16

Phenome

Answer 16

comprised of everything above it in the photo, together with the observable characteristic (phenotypes) of the organism/cell

Question 17

Infromation Flow

This is the connection between RNA, DNA and Protein

Answer 17

DNA, RNA and proteins are synthesized as linear chains of info with definite polarity (there is directionality to the way the information is being organized, because one side is 5’ and the other is 3’, the bottom is 3’ to 5’, so they are oppositely parallel)

Info in RNA sequence is translated into an AA (amino acid) sequence via a Genetic Code which is essentially Universal among all species

Question 18

Nucleic Acids

Answer 18

The genetic material in a cell (aka organisms blueprint); basically telling the cell all the instructions.

DNA = Deoxyribonucleic acid

RNA = Ribonucleic Acid

Question 19

The 3 parts of Nucleotides

Answer 19

Pentose Sugar (scaffold for base); is the connector between the base and phosphate group

Nitrogenous base (varies)

Phosphate group (backbone; 1,2, or 3 Phosphate groups)

Question 20

DNA bases

Answer 20

G, C, A, T

Question 21

RNA Bases

Answer 21

G, C, A, U

Question 22

Nucleoside monophosphate

Answer 22

Sugar + base + 1P

Question 23

Nucleoside diphosphate

Answer 23

Sugar + base + 2P

Question 24

Nucleoside Triphosphate

Answer 24

Sugar + base + 3P

Question 25

DNA is synthesized from

Answer 25

Deoxynucleotide triphosphates, aka dNTPs

Question 26

RNA is synthesized from

Answer 26

ribonucleoside triphosphates, aka NTPs

Question 27

Nucleosides are linked by

Answer 27

phosphodiester bonds

Question 28

Electrostatic Attraction

Answer 28

include ionic bonds, attractions between oppositely charged molecules; happen within and between larger molecules. Especially strong in the absence of water (not possible in cells, relatively weak)

Question 29

Hydrogen Bonds

Answer 29

weaker than covalent bonds, important for intermolecular bonds and structure (water). Initially and individually not strong, but the more of these you have the stronger it is. Usually includes an H+.

Question 30

Van der Waals Attraction

Answer 30

fluctuation in the distribution of electrons, causes a flickering dipole. Are not weakened by water.

Question 31

Hydrophobic force

Answer 31

all hydrogen bonding with hydrophilic things, pushing things that are non-polar out of the water and out of the bonding network.

Question 32

Base pairing

Answer 32

1. Holds the DNA double helix together 2. A-T is connected by 2 H-bonds G-C is connected by 3 H-bonds

Question 33

Purines

Answer 33

G, A 2 rings

Question 34

Pyrimidine

Answer 34

A, T, U 1 ring

Question 35

Forces that keep DNA strands together

Answer 35

1. Hydrogen bonds 2. Hydrophobic Interactions 3. Van der Waals attractions

Question 36

DNA has a ____ charge along its___ so it is quite___

Answer 36

Negative, backbone, hydrophilic

Question 37

Why are bases inside?

Answer 37

Bases are in the middle because H+ bonding bases are non-polar, so they are being pushed towards the middle (away from the water/hydrophilic conditions)

Question 38

5' groups is ____

Answer 38

Phosphate group (-PO_4)

Question 39

3' group is

Answer 39

Hydroxyl group (OH)

Question 40

Central Dogma (with DNA, RNA and protein)

Answer 40

In every cell, long polymer chains of DNA are made from the same set of four monomers (nucleotides), strung together in different sequences like the letters of an alphabet. DNA encodes information (info direct assembly of proteins) The information encoded in these DNA molecules is transcribed in RNA. RNA is translated into protein.

Question 41

Proteins in DNA replication and the central dogma

Answer 41

Proteins catalyze the replication DNA and it's transcription into RNA and they participate in the translation of RNA into proteins. They also catalyze many other chemical reactions that keep the self-replicating system (and others) running.

Question 42

Genome

Answer 42

The entire sequence of nucleotides in an organism's DNA. Provides a genetic program that instructs a cell how to function. Note: Different cells express different genes (produce some RNAs and proteins but not others)

Question 43

What are the three main domains | Cell and organism types

Answer 43

Eukaryote, Bacteria, and Archea

Question 44

Cytosol

Answer 44

Is the part of the cytoplasm that is not contained within the intracellular membranes. It is the largest single compartment Contains a host of large and small molecules Behaves like a water-based gel

Question 45

Cytoskeleton

Answer 45

A crisscrossed by long, fine filaments (is not a structureless soup) . A system of protein filaments. Actin filaments (thinnest); serve as a cental part of the machinery responsible for muscle contraction. They are abundant in all eukaryotic cells but occur in especially large numbers inside muscle cells Microtubules (thickest filament); have the form of minute hollow tubes. Are found in dividing cells, helping pull the duplicated chromosomes apart and distributing them to the daughter cells. Intermediate filaments (intermediate thickness); serve to strengthen most animal cells. Filaments + proteins form a system of girders, ropes, and motors that give the cell its mechanical strength, contols its shape and drives/guides its movements.

Question 46

Bacterial and Molecular model organism

Answer 46

E. Coli

Question 47

Simple Eukaryote Model Organism

Answer 47

Brewer's Yeast

Question 48

# ``` ``` Model Plant

Answer 48

Arabidopsis Provides insight into cell and molecular biology, specifically the mechanisms that enable plants to grow

Question 49

Model Animals (vertebrates)

Answer 49

Worms, flies, mice, and fish Sometimes humans too.

Question 50

Gene Expression

Answer 50

the process by which the nucleotide sequence of a gene is transcribed into the nucleotide sequence of an RNA molecule and then, translated into the amino acid sequence of a protein.