Exam 1: General Information Flashcards
Cells with the same morphology for function form???
Tissues
Anatomically discreet collections of tissues. they perform certain functions
Organs
Cells that make up a functional element of an organ
Parenchyma
structural framework of an organ or background tissue.
Stroma
Contains modified cells responsible for intercelluar communication
Nervous tissue
What happens to unfixed tissues??
The autolyze and dentature
What can be used to fix tissues in tissue preparation?
fix in FORMALIN, (37% formaldehyde). This causes cross-linking for proteins and preserve the tissue.
What are most common types of stains??
Hematoxylin- blue basic dye. This stains acids and is basophilic (blue/purple).
Eosin which is a red pink acidic dye which stains bases (esinophillic means red/pink)
What is another name for cell membrane
plasmalemma. This is semi-permable membrane (SPM)
What does amphoteric mean?
Able to reaction with both acids and bases.
What does Amphipathic mean?
Something that has both hydrophobic and hyrdophillic parts.
Describe the hydrophilic portion of the cell membrane
Contains + charged N Groups and Charged phosphate groups.
Describe the hydropobic portion of the cell membrane
This portion contains two long FA’s chains. These are covalently linked to glycerol.
Tri-laminar appearance of Cell membrane on EM
2 electron dense layers (phopholipid heads)
1 electron lucent layer of the FA tails
Describe changes in the fluidity of the cell membrane
Fluidity increases when the temperature increases and also increases with the decrease in the saturation of FA’s.
How does cholesterol function in the cell membrane
It decreases fluidity and stiffens the membrane.
What is the ratio of cholesterol to phopholipds
about 1:1
Synonyms for surface proteins
Peripheral, and extrinsic
What is an intrinsic protein?
is within the cell membrane also know as integral protein
Synonym for transmembrane protein?
transmural
Cell membrane channels
Allow the passage of water-soluble molecules via diffusion
What is a transducer in the cell membrane?
It initiates enzymatic rxns following the binding of ligand molecules
Enzymes
component of ion pumps and digestive action
What is a gyloccalyx ?
What are the two types?
What are their functions?
- cell membrane proteins or lipids conjugate with short polysac. chains containing glucose molecules.
- form glycoproteins and glycolipids
- protects the surface of cell memebrane, cell recogn. and importance in exchange of material inside and out of cell.
What is another name for bulk diffusion??
vesicular
What can increase the amount of passive and facilitated diffusion across the cell?
surface area via microvilli
where does active transport take place??
“Dynamic pore sites” usually transmmebrane proteins
Two types of Bulk (vesicular) Transport
Endocytosis= phago- and pino-
In receptor mediated transport, what is another name for the membrane receptor??
Clathrins or clatherin coated pit.
What are the two types of categories of organisms??
Prokaryotes: monera and cyannobacteria
Eukaryotes: single celled protists (protazo and metazoans)
Know the difference between Ekaryotes and Prokaryotes:
Prokaryotes:
- lack -
nucleus with envelope, membrane bound organelles, histones, lack axoneme
- circular DNA
Eukaryotes:
have nuclues, and organelles, complexed histones with dna,
What is the composition of protoplasm and what is it?
70-85% water; electrolytes, protiens, lipids, and carbohydrates
What percent of the nuclues does the genome take up?
20%
Chromatin
DNA and nucleoprotiens
Alleles
different forms of the same gene.
Diploid vs. Haploid
diploid in humans =46
haploid of sex cells =23
Karyotyping definition
sorting fo chromosomes pairs by shape and size
What is Heterochromatin?
electron dense, dark staining, inactive DNA and nucleoproteins
- FEMALES HAVE BARR BODY
- show degenerat X chromosome; only one pair active other degenreates
What is euchromatin?
disperesed, active DNA in transcription. (RNA Synthesis)
- cells with active transcription will have prominent nucleolus
What happens when Heterochromatin becomes Euchromatin?
Active portions of the chromosomes unravel to become visible as “lamp brush chromosomes”
What is a histone and how does it function?
The most common nucleoprotein.
Assists in DNA folding–> chromatin organization into chromosomes.
What is a nucleosome?
segments of DNA wrap around several histones to regulate DNA Activity.
NON-Histones
not histones, but are nucleoproteins which can help regulate gene activity.
What is the function of the nuckear envelope??
It separates the nucleoplasm from the cytoplasm
What are the layers of the nuclear envelop?
Inner Layer
Perinuclear Cisterna
Outer layer
What is unique about the inner nuclear membrane?
It is associated with a network of lamina called the nuclear lamina
What is unique about the Out nuclear membrane??
The outer surface is studded with robosomes. This layer is continuous with the ER.
What connects the inner and out nuclear membranes?
Nuclear pore complex.
This is a channel that is about 70-80 nm in diameter, and is surrounded with rings of proteins called, Nucleoporins.
What is a nucleoporin??
A ring of proteins that make up the edges of the nuclear pore complex in the nuclear pore complex.
What is the function of the nuclear envelop? AKA that nuclear membrane??
This regulates the exchange of macromolecules between the cyotplasm and the nuclearplasm.
How are ribosomes measured??
- Svedberg units
- Ribosomes are two subunits a 40s and a 60s
- They are proteinaceous and contain rRNA.
Where can you find Ribosomes
In the cytoplasm
On the ER
On the Nuclear Envelope!
What is a polysome or polyribosome?
It is a grouping of ribosomes.
What cells lack mitochondria?
RBC and Keratincoytes
What are some characteristics of the mitochondria outer membrane??
it is permable and and contains pore forming proteins called porins.
What are some characteristics of the mitochondria inner membrane?
Pleaded to form cristae.
On these cristae there are elementary paticles that contain enzymes for oxidative phos.
What fills the inner matrix?
There is an amorphous matrix material.
there are also dense granules that function to store CA.
Describes the genetic characteristic of Mitochondria
the DNA is maternal, it is circular and the mitochondria reproduce through binary fission,
Where does cell respiration begin?
In the cytosol with glycolysis.
Is glycolysis anaerobic or aerobic?
It is an anaerobic production.
What is produced form glycolysis?
Pyruvic acid which enters into the mitochondria through diffusion.
Where does the Krebs cycle take place.
In the mitochondrial matrix.
What is produced from the Krebs cycle?
CO2, H20 and ATP
What functions to cytochromes have in in the ATP cycle?
Cytochromes are a part of oxidative phos. and are located in the Electron Tranport Chain
Where are cytochromes located??
They are enzymes located on the inner membrane of the cristae.
What is the function of Smooth ER?
lipid synthesis
transport proteins from ER to golgi
membrane formation and recycling
It also functions in cholesterol and steroid hormone production, and is the site of detoxification and conjugation of drugs and toxins
The coated vesicles of the smooth ER are used for??
they are used for transport between the smooth Er and the golgi and the golgi to the cell surface.
What is the function of the golgi
The golgi function in post-translation modification.
This can include sulfation, phosphorylation, and gylcosylation