Cell Structure, Function, Organization Flashcards
eukaryote
What cells require alot of energy in the body to function? What organelle does this type of cell have the most of?
- skeleal muscle cell, neuronal cells
- mitochondria
eukaryote
What is found inside the nucleus?
- DNA (contains genes that will code for proteins), which are stored in chromosomes, which are highly condensed chromatin
- nucleolus: makes rRNA and ribosomes
remember: PROKARYOTES have NO nucleus, so the DNA and ribosomes are just free floating in the cytoplasm.
eukaryote
What processes occur in the nucleus?
DNA replication and DNA transcription into mRNA
eukaryote
Where does translation occur?
cytoplasm of the cell (done by ribosomes that are free (unbound) or bound to the rough ER)
What type of cells have alot of golgi?
secretory cells (ie. salivary gland cells)
Compare prokaryotes and eukaryotes aka what are the SIMILARITIES
- cell/ plasma membrane
- cytoplasm
- cytoskeleton
- DNA and ribosomes
Contrast prokaryotes and eukaryotes aka what are the DIFFERENCES
- nucleus status
- membrane organelle status
- mechanism of replication
biological hierachy
List the components of the biological hierachy from least to most complex
- chemicals: atoms –> moleulces –> macromolecules –> organelles (structures that allow for cell survival)
- cell = building block of a living organism
- tissues (groups of cells with similar function) - 4 types (epithelial, connective, muscle, nervous)
- organs
- organ systems
- organism
What are the 4 types of tissues?
- epithelial
- connective
- muscular
- nervous
Describe epithelial tissue (where is it found, characteristics of it)
- found in the lining of GI tract and other hollow organs (ie. respiratory tract and endothelium of blood vessels) and also the skins epidermis
Characteristics:
* Avascular and gets its nutrients from underlying basement membrane of connective tissue
* glandular (ie. oil secreted from skin and digestive juices from GI tract organs)
* named based on shape and arrangement (shape: squamous- flat, cuboidal, columnar- long); arrangement (simple- single layer of cells, pseudostratified- looks like multiple layers of cells BUT is not, stratified- multiple layers of cells)
Examples
* simple squamous (thinnest of the thin) - optimal for gas and nutrient exchange ( found in alveolar membrane of lungs and endothelium of blood vessels)
* simple columnar - lining of GI tract and fallopian tube
* stratified squamous - good for areas that get lots of friction (ie. epidermis of the skin, mouth, esophagus)
Describe connective tissue (where is it found, characteristics including function and what it’s made of)
- found throughout the body EXCEPT for the brain
Examples
* 3 fascial layers of the muscle (epimysium , perimysium, endomysium)
* tendons and ligaments (dense CT with LOTS of collagen)
* cartilage (made by chondrocytes)
* osseus tissue (bone tissue) made of osteocytes (mature bone cells) + bone matrix (INorganic Ca salts embedded into ORganic collagen fibers)
* adipose tissue (made of fat cells)
* blood (formed blood cells and plasma)
Characteristics
* HIGHLY vascular EXCEPT for tendons, ligaments, and cartilage
* funtion: protect and support the body
* made of ground substances- water, proteins, carbs- and protein fibers - COLLAGEN (MAIN one), elastin, reticular
Describe muscular tissue (where is it found)
- cardiac: heart myocardium
- skeletal: skeletal m. (when it contracts, it pulls the bone under it and moves it and so moves the entire body)
- smooth: generates the WEAKEST contractions bc of NO striations , so is present in the internal organs
Describe nervous tissue (where is it found)
- CNS- brain and spinal cord
- PNS- all the peripheral nerves (going to and from the brain via CN and the spinal cord via spinal nerves)
Note: NS comes from ECtoderm EXCEPT the CNS’s microglial, resident macrophages, come from MESODERM.
give an example of least to most complex of the biologial hierachy
lipids (macromolecule) –> neuron (cell) –> gray matter (tissue) –> brain (organ) –> CNS (organ system)
give an example of least to most complex of the biologial hierachy
lipids (macromolecule) –> neuron (cell) –> gray matter (tissue) –> brain (organ) –> CNS (organ system)
What organisms contain a cell wall?
plants, SOME bacteria, and fungi- yeast
animal cells and protists DO NOT have a cell wall & SO IS MORE FLEXIBLE
Contrast plant cells and animal cells
Animal cells - have centrosomes , NO cell wall
Plant cells- have all things animal cells BUT also contain a cell wall, chloroplasts carrying out photosynthesis (using sun light energy to generate glucose as food source), central vacuole (stores, water and glucose)
protists ALSO have NO CELL wall
What are the 2 prokaryotes?
bacteria and archae
What are the eukaryotes?
plants, animals, fungi-yeast, protists aka protozoans
The method of binary fission to replicate is asexual or sexual?
asexual (done by prokaryotes)
What is the purpose of the cell wall?
protect and support the cell and provide cell shape in plants, SOME bacteria, fungi- yeast
What does the cell/ plasma membrane divide?
inside of cell from outside environment
Describe the permeability of the cell membrane
selective permeability - small, NON polar (hydrophobic, water INsoluble) items are able to freely cross the membrane (ie. simple diffusion of gases like O2 and CO2) while large, POLAR (hydrophilic, water SOLuble) substances aren’t. (this is the door to the cell)
What is passive transport? What are the 3 major types?
taking a substance from HIGH to LOW concentrations (DOWN the concentration gradient) , so requires NO ATP (energy)
- simple diffusion of small, NONpolar (uses NO channels) ie. of O2 and CO2
- facilitated diffusion of large, POLAR (USES channels) ie. water aquaporin channels inserted by ADH/ vasopressin, glucose channels inserted by insulin, voltaged GATED Na and K channels)
- osmosis = diffusion of water from high to low concentration (either simple or facilitated through aquaporin channels)
Where is Na and K usually found (inside or outside the cell)? What maintains this gradient?
- Na: OUTSIDE the cell (think salt rim of a marg) - serum Na is 135-145
- K: INSIDE the cell- serum K is 3.5 -5.1
- Na/ K ATPase maintains this by pumping (3 Na OUT and 2 K IN)
very important for electrical impulse (AP ) conduction down axon, muscle contractions
What happens when voltage gated Na and K channels are open
- Na channels open = Na diffuses INTO the cell –> depolarize –> (skeletal m. contracts)
- K channels open = K diffuses OUT of the cell –> repolarize or hyperpolarizes (ie. dec contraction of cardiac m. cells)
going DOWN concentration gradient
What is active transport? What are some examples?
taking a substance from LOW to HIGH concentrations (against the concentration gradient), so it REQUIRES ATP (energy)
examples: Na/ K ATPase (pumps 3 Na + OUT and 2 K+ IN to the cell) , endo/ exocytosis (requires energy BUT doesn’t necessarily go against the conc. gradient)
Osmosis is what type of transport (active or passive)?
passive transport of water from high to low cocentrations so does NOT require energy