Cells Flashcards
(21 cards)
What are the main components of the cytoskeleton?
- Microfilaments (Actin Filaments)
- Intermediate Filaments
- Microtubules
What is the role of microfilaments?
They are crucial for muscle contraction, amoeboid movement, and form the structural core of microvilli.
What functions do microtubules serve?
found in all eukaryotic cells, and they are involved in mitosis, cell motility, intracellular transport, and maintenance of cell shape.
What distinguishes prokaryotic genetic material?
It consists of a single, circular chromosome located in a nucleoid region, which is not enclosed by a membrane.
What is the function of ribosomes?
They are responsible for protein synthesis.
What is the structure of the eukaryotic nucleus?
- Contains chromatin
- Surrounded by nuclear envelope
- Contains nucleolus
What is the function of the nucleolus?
It is the site of ribosomal RNA (rRNA) synthesis and the assembly of ribosomes
What is the endomembrane system?
A group of membranes and organelles in eukaryotic cells that work together to modify, package, and transport lipids and proteins.
What are the two types of Endoplasmic Reticulum (ER)?
- Rough ER (RER) -studded with ribosomes. Synthetize proteins for secretion.
- Smooth ER (SER) lipid synthesis, detoxification of drugs (liver), steroid hormones, storage calcium
What are lysosomes?
Membrane-bound sacs containing hydrolytic enzymes that digest cellular waste.
What is the role of chloroplasts?
They are the sites of photosynthesis, converting light energy into chemical energy.
Double membrane called Stroma
Thylakoid- a membrane sac where chlorophyll is found (captured energy)
Grana-attached to ^
What do peroxisomes do?
- Detoxify harmful substances -alcohol in liver
- Break down fatty acids
- Neutralize hydrogen peroxide
Share some detoxification function with smooth ER
What is the extracellular matrix (ECM)?
An intricate network of proteins and carbohydrates found outside of animal cells that provides structural support and plays roles in cell communication.
Cisternae
Received protein from ER cis =facing it
Trans face sends off for delivery
Phagocytosis
fuse with food vacuoles (phagosomes) or vesicles containing ingested pathogens, digesting their contents.
Autophagy
They break down and recycle old or damaged organelles.
The secretion pathway
- Proteins destined for secretion or other specific locations follow a path: synthesis in RER → transport vesicle → Golgi apparatus for further processing and packaging → transport vesicle → final destination (e.g., exocytosis from the cell). Doping tests can sometimes identify synthetic proteins by their lack of specific ER and Golgi modifications.
-
Plant cell three layers
Cell wall primary: made of cellulose, allows cell wall to expand. permeable, allowing water and other molecules in
Secondary cell walls, thicker and more rigid than primary cell walls.containing lignin, provide support in tissues like wood and maintain the shape of specialized cells like xylem cells.
The middle lamella, formed during cell division, connects adjacent cells by pectin, a ‘glue’ that holds them together. It also facilitates cell communication and material movement.
Nuclear Pore
Found within nuclear envelope that regulates what comes in and out the nucleus
Centrosomes
Found in most organelles, micro tubular- organization
Actin snd myosin
Actin is globular protein that forms to microfilaments. Aid in cell structure, muscle contraction
Myosin ATP dependent motor protein
