chapter 1 Flashcards
All living organisms are made of what?
one or more cells
What is the fundamental unit of structure and function in all living organisms?
CELL
Are all cells the same in chemical composition?
yes
What are the 7 simple molecules in the Miller-Urey experiments
water vapor, nitrogen (N2), ammonia (NH3), carbon dioxide (CO2), CO Methane (CH4) hydrogen (H2)
Was there any Oxygen in the Miller-Urey experiment?
NO
What were the results of the Miller-Urey experiment?
- aldehydes
- simple acids
- more complex acids (including amino acids)
What was the next step in the origin of life?
self-replication macromolecules
What might have been the first genetic system?
RNA
Ribozyme-catalyzed reactions are observed in what?
genome replication in some RNA viruses
intron splicing
ribosome function in translation
Some RNA molecules have what type of activity?
enzymatic activity
What has been observed in RNA but not DNA ?
Ana can catalyze the polymerization if nucleotides including the synthesis of complementary RNA using its self as a template.
Hypothetically: the ribozyme and the substrate of replication may be what?
Two domains of the same RNA molecule.
The first cells thought to consist of what?
Self-replicating RNA and other life-promoting molecules inside a phospholipid memrane.
A smaller cell has a ____ surface area to volume.
Greater
Smaller cells can interact with its surroundings more_____.
Efficiently
Smaller cells are more likely to ____ energy as heat to their _____.
lose,
surroundings.
Prokaryotes lack what?
Nuclear envelope
membrane bound organelles
cytoskeleton
What type of cells are the most diverse?
Prokaryotes
Photosynthetic bacteria get their energy from____.
Sunlight
The membrane that uses the sunlight and converts it to energy for the photosynthetic bacteria is_____.
Chloroplast
The Anabaena cylindrica form filaments of what type of specialized cells?
nitrogen fixing
photosynthetic
weather-resistant spores
Phormidium laminosum contains intracellular membranes where ______ occurs.
Photosynthesis
The filamentous bacteria beggiatoa can live in what kind of environment?
A hydrogen sulfide contaminated marine environment.
What does chemosynthetic mean?
Derives energy from oxidation of hydrogen sulfide
The nucleus of the eukaryotic cell contains ______ of the DNA in the cell.
MOST
Mitochondria
organelles found in the eukaryotic cell and generate most go the cells supply of usable energy.
DNA containing organelles
Enclosed by a double membrane
Chloroplasts
Organelles found in plant cells and eukaryotic algae.
harvest energy from the sunlight by photosynthesis
DNA containing organelles
larger than mitochondria
2 membranes + 3rd membrane system which contains the photosynthetic pigment
What is the name of the 3rd membrane of the chloroplast that contains the photosynthetic pigment?
thylakoid
What is the photosynthetic pigment called?
chlorophyll
Endocytosis
Import mediated by the formation of endocytic vesicles
Exocytosis
Export of the cell
Endosymbiosis
mitochondria and chloroplasts were prokaryotes that entered eukaryotic cells and became specialized to perform specific cellular functions.
Evidence for endosymbiosis
resemble present day prokaryotes in size
contain their own DNA
organelles can divide independent of mitosis and cell division.
enclosed in double membrane.
Mitochondria and chloroplast can ____survive ousted of the cell.
NOT
The presence of organelles ___________ define eukaryotes.
DOES NOT
Animal cells consist of:
nucleus chromosomes mitochondria centrioles no cell wall
plant cells consist of:
nucleus chromosomes mitochondria chloroplast no centrioles, but still have some type of microtubule organizing center. large vacuoles cell wall
Epithelial cells:
bound by tight junctions and form sheets that cover body surfaces and form the lining of internal organs.
connective tissue
bone and cartilage
adipose tissue
fibroblasts
Blood cell types
red and white
Red blood cells need what to divide?
Stem cells
neurons
Are cells that receive and transmit signals throughout the body and are capable of generating electrical activity
Dentrite
a short branched extension of a nerve cell, along which impulses received from other cells at synapses are transmitted to the cell body.
(by the Soma)
Soma
neuron cell body
Axon
also known as a nerve fibre, is a long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron’s cell body.
Axon terminal
(also called synaptic boutons) are distal terminations of the branches of an axon.
Muscle cells
Are multi-nucleated cells that generate force and movement
What are the three types of muscle cells?
skeletal
cardiac
smooth
Is a virus alive?
NO
What distinguishes cells from other non-living entities?
Cells are highly complexed and organized
cells possess a genetic program and the means to use it
cells are capable of producing more of themselves
cells are capable of acquiring and utilizing energy.
cells carry out a variety of chemical reactions
cells engage in numerous mechanical activities
cells are able to respond to external stimuli
cells maintain their complex state by constant self-regulation
What is an example of response and self-regulation of a cell?
The sea urchin.
an isolated cell recognizes and respond to absence of its partner and regulates regular development to complete an entire embryo.
Most of our knowledge and studies (DNA replication) have come from this cell
E. coli
single circular chromosome
encodes ~4300 different proteins
dna replication and decoding genetic instructions.
What is a simple eukaryote thats observed?
saccharomyces cerevisae
can reproduce almost as rapidly as bacteria
2x as much DNA as bacteria
mechanism of cell division cycle
What is a simple model plant that is observed?
arabidopsis thaliana
can be grown indoors, produces thousands of offspring
genome 8x as large as yeast
evolution of flowering plants
model animal for studies
drosphila melanogaster
embryonic development, neurobiology, behavior, cancer
mutants
13000 genes
model animal
caenorhabditis elegans transparent nematode worm: can follow development in detail allowed for the understanding of programmed cell death 19000 genes
model organism for fish:
Danio rerio
rapid embryonic development ~3 days.
transparent as embryos and juveniles
model organism for mammal:
mus musculus
used to study mammalian genetics, development, immunology, cell biology
almost every human gene has a counter part in mouse.