1.02: Cells Flashcards
Double Membrane Bound Organelles
Nucleus and Mitochondria
Single Membrane Organelles
ER, Golgi, Lysosomes
Nonmembrane Organelles
Ribosomes, centrosomes, basal bodies
Passive Transport
- simple diffusion
- osmosis
- facilitated diffusion
Active Transport
- Ion pumps
- Vesicles (endocytosis + exocytosis)
Microfilaments
Actin
7 nm diameter
Intermediate Filaments
In Keratin and Vimentin
8-10 nm diameter
Microtubules
Tubulin arranged to form hollow tubes
Important for cilia and centrioles
25 nm diameter
Microvilli
- short projections that increase SA:Vol ratio
- contain microfilaments
- nonmotile
Stereocilia (Stereovilli)
- like microvilli, but longer
- also increase SA:Vol ratio
- Nonmotile
Cilia
- 9x2 + 2
- often motile
- most non-epithelial cells have nonmotile sensory primary cilium
Flagella
- motile fail of sperm
- same internal microtubule structure as cilia
Where do cilia attach to?
Basal bodies at the apical margin of the cell
Axoneme
(9 x 2) + 2
Do sensory, nonmotile cilia have a central pair?
NO
Centrioles
- microtubules arranged in 9 sets of triplets in a circular pattern
- important in mitotic spindle formation for cell division
- generate new microtubules
Centrosome
2 centrioles, microtubules organizing center
What are the basal bodies of cilia made of?
centrioles
Mitochondria
- aerobic cellular respiration
- early role in Apoptosis
- contain circular mitochondrial DNA
Rough ER
- continuous with outer nuclear membrane
- has ribosomes
- cisternae (interconnected flat tubules)
- produces proteins for lysosomes or cell membrane
Where do proteins produced by free ribosomes go?
The cytoplasm
Smooth ER
- Lacks ribosomes
- synthesizes phospholipids, cholesterol, and steroids
Golgi Apparatus
- cisternae
- cis side nearest ER is convex
- Trans face is where vesicles depart, concave
Peroxisomes
oxidative digestion
Nucleolus
- NOT membrane bound
- site of ribosome synthesis
Heterochromatin
Densely packed, stains darker
Euchromatin
loosely packed, stains lighter
G1 Cell Cycle Phase
Replication of organelles and cytoplasm
S Phase of Cell Cycle
DNA replication
G2 phase of Cell Cycle
growth + protein synthesis
Prophase
- chromosomes condense
- centrioles move to opposite ends
- nuclear envelope disappears
Metaphase
Chromosomes align along metaphase plate
Microtubule Organizing Center
- assembles around centrioles
- serve as mitotic spindle poles
kinetochore
Where spindle attaches to the centromere region of chromosome
Anaphase
Chromosomes are pulled apart
Telophase
- chromosomes decondense
- nuclear envelope reforms
- nucleolus reappears
cytokinesis
Formation of 2 daughter cells
Inclusions definition
Cytoplasmic or nuclear structures that are nonliving components of cell
Inclusion examples
- secretory vesicles
- lipid droplets
- mucus in goblet cells
- granules (glycogen)
- pigments (melanin, lipofuscin)