Chapter 1: Life Flashcards
Prokaryotes have what basic organelles
- Ribosomes
- Flagella
- Nucleiod
- Pili
- Mesosome
- Cell wall
- Cell membrane
What is the cytoplasm of prokaryotic cell?
- single chromosome (DNA molecule) is condensed to form the nucleiod
- also contains numerous species of RNA
- contains a variety of enzymes
- contains thousands of ribosomes
Ribosomes are the site of what?
protein synthesis
Flagella are used for what?
locomotion
Pilil are used for what?
Sexual conjugation and for aiding in the attachment of bacterium to host cell
The nucleus is a structure of what?
Eukaryotic cells
The Nucleus is surrounded by what? and contains what?
Surrounded by a double membrane and contains a necleolus
How is the surface to volume ration different for eukaryotics than prokaryotics? why?
Eukaryotics have a much smaller surface to volume ratio than prokaryotics. This is because surface area increases as square of its radius where as volume increases as the cube.
The nucleus contains chromosomes which consist of what?
-chromatin, a complex of DNA and protein
In the nucleus the genetic material encoded by the DNA is transcribed into molecules of RNA which after extensive processing are what?
transported to cytoplasm where they direct ribosomal synthesis of proteins
The nuclear envelope consist of what?
double bound membrane that is perforated by numerous ~90 A- wide pores that regulate the flow of proteins and RNA between the nucleus and and cytoplasm
Nucleolus is the site of what?
Ribosomal assembly and is where genes are transcribed
After genes are transcribed in the nucleolus their resulting RNA is what?
combined with ribosomal proteins that have been transported from their site of synthesis in the cytosol.
After genes are transcribed and combined with ribosomal proteins in the nucleolous what happens?
The resulting immature ribosomals are then exported to the cytosol where their assembly is completed.
Protein synthesis occurs mostly entirely where?
In the cytosol.
What is the most extensive membrane in the cell?
Endoplasmic reticulum
The rough endoplasmic reticulum is what?
studded with ribosomes that are engaged in the synthesis of proteins that are either membrane-bound or destined for secretion.
The smooth endoplasmic reticulum is what?
devoided of ribosomes and is the site of lipid synthesis.
Many of the products synthesized in the endoplasmic reticulum are eventually transported where?
Golgi apparatus
What is the Golgi apparatus?
Is a stack of flattened membranous sacs in which these products are further processed.
Mitochondria is the site of what?
site of cellular respiration in almost all eukaryotes
Mitochondria have what shape?
vary in size and shape but are often ellipsoidal
The mitochondria has two membranes. The outer membrane is what?
has a smooth outer membrane and a highly folded inner membrane with invaginations called cristae.
The mitochondria has two membranes thus two compartments which are:
1) Intermembrane space
2) matrix space
The enzymes that catalyze the reactions of respiration are components of what?
- either the gel like matrix
- or mitochondrial membrane
The matrix space of the mitochondria contains wha?
- DNA
- RNA
- Ribosomes that participate in the synthesis of several mitochondrial components.
What are lysosomes?
Single membrane bounded organelle; Lysosomes contain a variety of hydrolytic enzymes that function to digest materials ingested by endocytosis and recycle cellular components.
How do lysosomes form?
Budding from the Golgi apparatus.
Peroxisomes are also called microbodies which are what?
membrane-enclosed organelles
Peroxisomes contain what?
oxidative enzymes
What are peroxisomes function?
function to protect sensitive cell components from oxidative attack by hydrogen peroxide.
what is the cytoskeleton?
an extensive array of filaments that gives the cell its shape and ability to move. It is also responsible for the arrangement and motion of its organelles.
Nucleic acids are polymers of what?
Nucleotides
Proteins are polymers of what?
amino acids
Polysaccharides are polymers of what?
monosaccharides
Anabolism is responsible for what type of synthesis?
Fatty acid
What does Anabolism do?
Converts small compounds to larger compounds
Catabolism produces what?
produces ATP
What does catabolism do?
Converts large compounds to smaller compounds
What is result of Translation of RNA
protein
What is the result of transcription of DNA
RNA
What is the reverse transcription of RNA
DNA
What is the result of replication of DNA
DNA
What are the major components of organic molecules?
Carbon and Nitrogen
microtubules are composed of what?
The protein tubulin
What is the function of microtubules?
They form supportive framework that guides the movements of organelles within a cell.
What are mitotic spindles?
An assembly of microtubules and associated proteins that participate in the separation of replicated chromosomes during cell division.
microfilaments consist of what protein?
actin protein
microfilaments interact with the protein myosin to do what?
form contractile assemblies that are responsible for many types of intracellular movements such as cytoplasmic streaming and the formation of cellular protuberances or invaginations.
What are the three major components of the cytoskeleton?
- Microtubules
- Microfilaments
- and Intermediate filaments
Intermediate filaments have what function?
Load bearing function
Keratin has an extensive network of what?
Intermediate filaments
Plant cells have a cell wall composed of what?
Cellulose
On addition to the organlles as most eukaryotes what additional features do plant cells have?
- cell wall
- chloroplast
what is a vacuole?
membrane-enclosed space filled with fluid
What cells do vacuoles appear in?
animals and plants but more prominent in plant cells where they occupy 90% of the volume of a mature cell.
Vacuole function as what?
storage depots for nutrients, wastes, and specialized materials such as pigments.
The realitively high concentration of solutes inside a plant vacuole causes what?
causes it to take up water osmotically, thereby raising its internal pressure.
chloroplast is what?
site of photosynthesis and generally several times larger than the mitochondria
chloroplast has how many membranes?
2 membranes: internal and external
Stroma is what?
Is the choloroplast’s internal membrane space which is similar to the mitochondria matrix in that it contain many soluble enzymes. however the stroma is not folded intro cristae.
The stroma encloses what?
third membrane system what forms interconnected stacks of dislike sacs called thylakoids.
Thylakoids are located where and does what?
located in the stroma which is located in the internal membrane space of the chloroplast; the thlakoids contain the pigment chlorophyl II
