Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key

image

Play button

image

Play button

image

Progress

1/67

Click to flip

67 Cards in this Set

  • Front
  • Back
Cells are what?
small membrane-enclosed units filled with a concnetrated aqueous soluiton of chemicals.
Cells can create ___ of themselves by____ and ____ ?
Cells can create copies of themselves by growing and dividing in two.
living things exist as ____ or ____
Living things exist as solitary cells or as communities of cells derived from grwoth and divsion of a sigle founder cell.
What does cell biology address?
Fundamental question of life.
What are the fundamental question of life?
1. What is life?
2. How did life areise on earth?
3. How did so many diverse forms of life arise and populate the earth?
4.How do we, and othe rmulticellusar oranisms, develop from a single cell?
5.Why do we get sick, grow old, die?
Cells vary enormously in ___ and ___?
In appearance and function.
The discoveries of ___ gives us a clearer view of life?
molecular biology.
What is the definition of life?
The discoveries of molecular biolgoy give us a clearer view of life: all living things chare a fundamental chemical machinery for grwoth and reproduction.
All living cells have a similar fundamental chemistry, what is it?
1. DNA synthesis (replication)
2. RNA synthesis (transcription)
3. Protein synthesis (translation)
All present-day cells must have evolved form a common ancestor. What is it and how long has it estimated to have lived from?
LUCA (last universal common ancestor)

Estimated to have lived 3.5-3.8 billion years ago.
LUCA estimate is basted on what?
Based on comparing DNA seequences of organism alive today.
What is a descripiton of LUCA?
1.Must have been a cell with DNA as the information repository,
2.Must have had the same basic machinery to replicate DNA and to translate DNA sequence into protein as all orgainisms have today.
What allows for the generation of diversity among living things?
the abilityof DNA sequences to code for an immense variety of proteins, which adapt different confromations.
How do cells reproduce?
By duplicating their DNA and dividing in two.

DoubleD
When copying of DNA is not perfect what happens?
1. Mutations arise that change the DNA sequence

2. Daughter cells therefore don't exactly match the parent cell.
What 3 characteristics do mutations possess?
1.Most are deleterious
2.Some are neutral
3.Few imporve reproduction ofthe resulting organism.

The next generation may therefore include more individuals with the mutation.
Mutation and natural selection lead to what?
diversity and adaptation
Who discovered cells and by what?
Robert Hooke (1665)

by microscopyof thin slices of cork
What did early microscopy showed?
That new cells form by division of existing cells.
The Cell Theory
1. All cells arise from preexisiting cells

-first proposed by Schwann, Schleiden and others in 1830's (used animal and plant tissues)

-Louis Pasteur confirmed this theroy in 1860's
The Law of Biogenesis:
Omne vivum ex vivo

all life [is] from life
Who tested this assumption using a flask and declared it a dream?
Pasteur's used a flask to test spontaneous generation.
What can microscopy reveal?
the internal structures of cells.
-up to organells and molecules
What can not be viewed by microscopy?
atoms
Light microscopy allows us to see structures larger ____?
than 0.2 um (200 nm)
Electron microscopy is used for____?
Higher magnification (shows structures larger than .2 nm - 200 nm)
What are the two major types of organisms ?
Prokaryotes & Eukaryotes
Major difference btwn prokaryotes and eukaryotes?
Eukaryoes have a nucleus
Description of (all) Prokaryotes
1. Small
2. Can reproduce quickly
3. Most are single celled
4. incredibly diverse
Description of (diverse) Prokaryotes
1. Enorous range of habitats
2. Some are aerobic other are ananerobes
3.Different pro- use diff. organic material as food
4. some can live entirely on inorganic materials
Def. Aerobic
use oxygen to brek down food molecules
Anaerobes
poisoned by oxygen.
What is Anabanena cylindirica
a photosyntheic bacterium that forms long multcelular filaments
What does Anabaena c. 3 differnent cells do?
1. fixes nitrogen
2. fixes Co2 (through photosynthesis)
3. one becomes a spore.
A bacterium gets energy by doing what?
by oxidizing H2S to produce sulfur.
What are the two classes (domains) of prokaryotes?
bacteria & archaea
How are bacteria and archaea differnt form each other? How are they same
chemically differnet
bot live in everyday enviroments (archaea can live in extreme)
Differenent shapes and sizes of bacteria
spherical
rod-shpedcells
spiralcells

most few microns (um) in diameter
Description of (all) Eurkaryotic cell
1. all euckaryotes have a nucleus
2. All have mitochondria & other compartments
3. Internal membranes create cellular compartments
4. The cytosol: aqueous gel
5. They cytoskeleton: networks of fibers.
What are 4 examples of cellular compartments created by internal membranes?
1.ER
2.Golgi apparatus
3. lysosomes
4. peroxisomes.
Description of (diverse) Eukaryotic cell
1.Plants and algae are eukaryotic cells taht have chloroplasts
2. Many organisms are multicellulsar
A example of a single celled eukaryote
Saccharomyces cervisiae
What unique characteristic does the eukaryotic cell nucleus have?
2 cooncentric membranes with DNA enclosed inside.
What happens during cell divsion in eukaryotic cells?
DNA becomes compacted and thus visible
What is the fuction mitochondria?
-Organelles in which food molecules are oxidized to produce ATP
What is the structure of the mitochondria?
-have an outer membrane and an extensively folded inner membrane.
"Nucleus first" theory
Theory on the orgin of mitochondria.

1. Ancestral eucaryotic cell containing a nucleus and internal membranes enculfed a bacterium.
2. Bacterium develops into mitochondira
"Mitochondria first" theroy
Theroy on the orgin of eukaryotes.
-eukaryotic nucleus marked a seminal evolutionary transition
-the nuclear envelops fuction was to allow mRNA splicing to go to completion
-compeltion of splicign allwos translation to occur only on mRNA with intact reading frames.
-fast spread of introns forced nucleus -cytosol compartmentalization.
What is the fuction of the chloroplast?
to capture enery from sunlight to do photosynthesis
What is the structure of the chloroplast?
1.chrlophyll containing membranes
2. inner membrane
3. outer membrane
Evolution of chloroplast?
Chlroplasts eveolved from engulfed bacteria
1. Early eucaryotic cell (with mitochondria) engulf a photsytheic bacterium which forms into chloroplasts.
rough ER
a membrane network studded with ribosomes
Gogli apparatus
stacks fo flattened discs
Lysosomes
sites of intracellular digestion
Peroxisomes
isolate reactions with hydrogen peroxide
Fuction of plasma membrane
plasma membrane allows for continuous import and export of materials
Cytoplasm
stuffed with organells and large and small moleules (proteins polyscaharisdes)


everything in the cell except the nucleus


1. part of the cell which is contained within the entire cell membrane.
2. made of water up to 80% nucleic acids, enzymes, lipids, non-organic ions, amino acids, carbohydrates, and lightweight molecular compounds.
3.large scale cellular activities including glycolis, cell division and other metabolic paths take place in the cytoplasm.

Cytosol
1.Cytosol is the intra-cellular fluid that is present inside the cells.
2.comprises of a lot of water, dissolved ions, large water soluble molecules, smaller minute molecules and proteins
3.all the metabolic chemical reactions of prokaryotes take place.

soluble portion of the cytoplasm
Cytoskeleton
a network of filaments inside the cell
-actin
-microtubuels
-intermediate filaments
Microtubules
help to distribue chromosome sin a dividing cell
What did eukaryotes may have resembled before engulfing bacteria?
protozoa
What are protozoans
single celled orgnism that have among them the most complex cell architectures and diversity of function known
What are 6 methods to study cells
1. microscopy
2. cell fractionation
3. biochemistry
4. X-ray chrystallography
5. gentic analysis and molecular geneics using model orgnaisms
6. gneome comparisons
Model eukaryote
S. cerevisiae (brewer's yeast)
model plant for genetic analysis
Arabidopsis thaliana
Similar mutaionis in ____gene cause similar phenotypes in people and ___?
kit gene
mice
What is an excellent model system for studying cell division?
Yeast