Topic 3: Cellular Level of Organization Flashcards
The Cell
- Basic structural and functional unit of the body
- can perform all basic life functions
- atom loses election and becomes a positive ion (cation)
Principle Parts of the Cell
- Cell membrane/Plasma membrane/Plasmalemma
- Cytoplasm
- Non-membranous organelles
- Membranous organelles
- Nucleus
Principle Parts of the Cell
Cell Membrane/Plasma Membrane/Plasmalemma
composed of?
- Phospholipid bilayer
- Cholesterol
- Membrane Proteins
- Membrane carbohydrates
- Microvilli
Principle Parts of the Cell
Cell Membrane/Plasma Membrane/Plasmalemma
composed of?
Phospholipid bilayer
- phosphate head group (hydrophilic)
- FA tails (hydrophobic)
- Divides ICD + ECF
- →intracellular fluid (ICF) = inside cell
- →extracellular fluid (ECF) = outside cell
Principle Parts of the Cell
Cell Membrane/Plasma Membrane/Plasmalemma
composed of?
Cholesterol
- scattered throughout membrane
- adds stability to the cell membrane
Principle Parts of the Cell
Cell Membrane/Plasma Membrane/Plasmalemma
composed of?
what are the types of membrane proteins
- integral proteins
- peripheral proteins
Principle Parts of the Cell: Cell Membrane/Plasma Membrane/Plasmalemma is composed of?
Membrane Proteins: integral proteins
- what does it contain?
- what do some do and what is that called?
- within a membrane have a hydrophobic region
- some extend across entire membrane = transmembrane (some do not extend throughout entire membrane)
Principle Parts of the Cell: Cell Membrane/Plasma Membrane/Plasmalemma is composed of?
Membrane Proteins: peripheral proteins
- attached to either surface of integral proteins
Principle parts of the cell
Cell Membrane/Plasma Membrane/ Plasmalemma composed of?
Membrane carbohydrates
- only on outer surface
- bound to proteins (glycoproteins) or lipids (glycolipids)
- functions
- cell recognition (e.g. egg and sperm)
- anchor cells together
Principle parts of the cell
Cell Membrane/Plasma Membrane/ Plasmalemma composed of?
Microvilli
- definition:
- function:
- where is it best seen?
- small projections of cell membrane
- function
- increase surface area
- best seen on cells of the small intestine and kidney
function: microvilli
increase surface area
function: membrane proteins
- enzymes
- transporters
- channels
- receptors
- anchors - hold cells to one another
- identity markers (for immune system)
function: mebrane carbohydrates
- cell recognition (e.g. egg and sperm)
- anchors cell together
Fluid Mosaic Model of the cell membrane:
Fluid
Mosaic
fluid: membrane constituents can move around (phospholipids + some proteins)
mosaic: proteins dot durface like tiles in a mosaic
Principle parts of the cell
Cytoplasm
- where is it located?
- how many divisions?
- AREA between the inside of the cell membrane and the outside of the nucleus
- 2 divisions
Melanin
Skin color
Glycogen
stored glucose
Polysaccharide
Cytoplasm
Cytosol
- one of the two divisions of cytoplasm
- gel-like intracellular fluid
- contains water and a suspension of carbohydrates, proteins, and lipids
- may contain inclusions
- example: melanin, glycogen
Cytoplasm
Organelles
- one of the two divisions of cytoplasm
- structures that perform a specific function and are essential for life
-
non membranous
- in direct contact with cytosol
-
membranous
- surrounded by membrane that isolates them from the cytosol
-
non membranous
Cytoplasm → Organelles
non membranous
in direct contact with cytosol
Cytoplasm → Organelles
membranous
surrounded by membrane that isolates them from the cytosol
Principle parts of the cell
Non-Membranous organelles
- ribosomes
- centrosomes
- cytoskeleton
Principle parts of the cell → Non-Membranous Organelles
Ribosomes
- what happens here?
- site for what?
- what does it contain?
-
may be located where?
- what is the difference between where they are located?
- where we take amino acids to join covalent bonds
- sites for protein synthesis
- contain ribosomal RNA (rRNA) + proteins
- may be:
- free in cytosol - make proteins destined for cytosol, mitochondria, nucleus
- attached to endoplasmic reticulum (ER) - make proteins destined for all other sites
- free in cytosol - make proteins destined for cytosol, mitochondria, nucleus
what does the ribosome contain?
proteins and have own RNA
Principle parts of the cell → Non-Membranous Organelles
Centrosomes
- dense area of cytoplasm, usually contains 2 centrioles (function uncertain - some cells lack them)
- organizes microtubules to form spindle apparatus (for cell division)
- organizes cytoskeleton
Principle parts of the cell → Non-Membranous Organelles
Cytoskeleton
- what does it determine?
- it is formed by what?
- what is its function?
- what are the types of cytoskeletons?
- determines cell shape (cell support)
- Formed from proteins
- functions:
- important in cell movement, cell division, movement/anchoring of organelles + proteins (e.g. receptors, enzymes)
- 3 types:
- microfilaments
- intermediate filaments
- microtubules
Principle parts of the cell → Non-Membranous Organelles→ Cytoskeleton
Microfilaments
- made of actin → made of protein
- function:
- muscle contraction (with myosin)
- cell locomotion
- maintenance of cell shape and projections (e.g. microvilli)
- cytokinesis
Principle parts of the cell → Non-Membranous Organelles→ Cytoskeleton
function: microfilaments
- muscle contraction (With myosin)
- cell locomotion
- maintenance of cell shape and projections (e.g. microvilli)
- cytokineses
Principle parts of the cell → Non-Membranous Organelles→ Cytoskeleton
intermediate filaments
- composition is tissue specific
- e.g. keratin
- function
- support the cytoplasm (scaffolding for the cell)
Principle parts of the cell → Non-Membranous Organelles→ Cytoskeleton
function: intermediate filaments
- support the cytoplasm (scaffolding for the cell)
Principle parts of the cell → Non-Membranous Organelles→ Cytoskeleton
Microtubules
- hollow tubes made of tubulin
- function
- form:
- centrioles
- spindle apparatus
- cilia (short)
- flagella (long)
- structural → make up structure of cells skeleton
- move or secure organelles in place
- form:
what functions do the membrane proteins have?
- enzymes
- transporters
- channels
- receptors
- anchors -> holds cells to one another
- identity markers (for immune system)
fluid mosaic model of the cell membrane
fluid - mebrane constituents can move around (phospholipids + some proteins)
mosaic - proteins dot surface like tiles in a mosaic
what are the 2 divisions of the cytoplasm?
- cytosol
- organelles
describe the cytosol of the cytoplasm
- gel like intracellular fluid
- contains water and a suspension of carbohydrates, proteins, and lipids
- may contain inclusions …e.g. melanin (pigment), glycogen (stored glucose)
describe the organelles of the cytoplasm
- structures that perform a specific function and are essential for life
- 2 types
what are the 2 types of organelles of the cytoplasm
- non membranous
- membranous
describe the non-membranous organelles of the cytoplasm
- in direct contact with cytosol
describe the membranous organelles of the cytoplasm
surrounded by membrane that isolates them from the cytosol
Name the membranous organelles
- Mitochondria
- Endoplasmic Reticulum
- Golgi apparatus
- Lysosomes
Membranous Organelles
Mitochondria
- site of ATP synthesis
- contains own DNA, RNA, + proteins
- have a double membrane
Membranous Organelles
ER
- Membranous network throughout the cytoplasm
- 2 types
- rough ER
- smooth ER
Rough ER
- ribosomes attached - synthesis of secretory, lysosomal and membrane proteins
Smooth ER
- Lacks attached ribosomes
- continuous with Rough ER (RER)
- synthesized lipids + steroid hormones
Membranous Organelles
Golgi Apparatus/Complex
- stacks of membrane discs
- modifies (e.g. trims or adds CHO groups), sorts, packages, and delivers proteins/lipids to cell membrane, lysosomes, or for secretion (cellular post office)
Membranous Organelles
Lysosomes
- break down things
- filled with digestive enzymes
- digest bacteria, viruses, worn-out organelles (clean up function)
Nucleus
- definition
- also what are the parts of the nucleus?
- cells may have one or more nuclei true or false?
- Largest membranous organelle
- cell control centre
- cells may have 1 or more nuclei
- Parts:
- nuclear envelope
- nucleolus
- chromosomes/chromatids
nuclear envelope of nucleus
and what is it CONNECTED to
- double membrane with nuclear pores
- connected to ER
nucleolus (>1 in some plants)
-what region?
- non-membranous
- dense (less light gets through) region of DNA, and proteins where ribosomes are made and assembled
chromosomes/chromatids of nucleus
- contain DNA + histone proteins
- can be:
- dipersed = chromatin
- condensed + individually visible
dispersed = chromatin of chromosomes of chromatids
- DNA uncoiled + not individually visible
- in this form MOST of the time (when cell is not dividing)
condensed + individually visible chromosomes
- found in dividing cells (during mitosis/meiosis)
what organelle containts
ribosomal RNA + proteins?
ribosomes
what contains water and suspensions of carbs, proteins, and lipids?
cytosol
what organelle has these functions?
- muscle contraction (With myosin)
- cell locomotion
- cytokinesis
- maintance of cell shape and projection
microfilaments
what may contain inclusions?
cytosol
what has these functions?
- enzymes
- transporters
- identity markers (for immune system)
- receptors
- anchoring (hold cells to one another)
- channels
membrane proteins
what forms:
- spindle apparatus
- centrioles
- cilia (short)
- flagella (long)
microtubules
what makes up structure of cells skeleton?
microtubules
what moves or secures organelles in place?
microtubules
what has this function?
cell recognition?
membrane carbohydrates
what has this function?
anchors cells together
membrane carbohydrates
largest membrane organelle
nucleus
cell control center
nucleus
dense region of DNA and proteins where ribosomes are made and assembled
Nucleolus
what organelle organizes microtubules to form spindle apparatus?
centrosomes
what is made of actin?
microfilaments
small projections of cell membrane
microvilli
what increases surface area
microvilli
what is best seen in small intestine and kidney?
microvilli
what is important in cell division, cell movement, movement/anchoring of organelles and proteins?
cytoskeleton
what contains DNA + histone proteins
chromosomes
what are bounded to glycoproteins and glycolipids
membrane carbohydrates
hollow tubes made of tubulin
microtubules
membranous network throughout cytoplasm
ER