Kaarten: bio unit 2.9/2.10 | Quizlet

what is the function of the nucleus

stores DNA and controls gene expression; acts as the contol center of the cell

what is the nucleolus

the region in the nucleus where ribosomes are assembled

What is the function of ribosomes?

synthesize proteins by translating mRNA

what is the function of the rough ER

modifies and folds newly made proteins; ribosomes attached to its surface

what is the function of the smooth ER

synthesis lipids, detoxifies toxins and stores calcium

What does the Golgi apparatus do?

Modifies, sorts, and packages proteins for secretion or transport.

What is the function of lysosomes?

Break down waste materials and cellular debris using hydrolytic enzymes.

What is the function of peroxisomes?

Break down fatty acids and detoxify harmful substances using peroxide reactions.

What is the function of mitochondria?

Produce ATP through cellular respiration (energy powerhouse).

What is the function of chloroplasts?

Conduct photosynthesis to produce glucose and oxygen.

What is the function of vacuoles?

tore water, nutrients, or waste; central vacuole helps maintain turgor pressure in plants.

What do vesicles do?

Transport materials within the cell or to/from the plasma membrane.

What is the cytoskeleton

Network of protein fibers (microtubules, microfilaments, intermediate filaments) that support cell structure and movement.

What is the function of centrioles

Help organize spindle fibers during cell division in animal cells

What is compartmentalization

The separation of different cellular processes into membrane-bound organelles to increase efficiency

Why is compartmentalization important

It isolates incompatible chemical reactions and creates optimal environments for different processes.

How do mitochondria demonstrate compartmentalization

They have separate compartments (matrix, intermembrane space) for different steps of cellular respiration

How do chloroplasts demonstrate compartmentalization

Thylakoids hold light-dependent reactions; stroma contains enzymes for the Calvin cycle.

What is the surface area-to-volume ratio

Measurement that determines how efficiently a cell exchanges materials with its environment

Why do cells need a high surface area-to-volume ratio

Higher SA:V allows faster diffusion of nutrients, gases, and wastes

What is the endosymbiotic theory

The theory that mitochondria and chloroplasts originated when early eukaryotic cells engulfed prokaryotes that became symbiotic partners

What evidence supports endosymbiotic theory regarding DNA

Mitochondria and chloroplasts contain circular DNA, similar to bacteria

What evidence supports endosymbiotic theory regarding membranes

Mitochondria and chloroplasts have double membranes, suggesting engulfment

What evidence supports endosymbiotic theory regarding reproduction

Mitochondria and chloroplasts reproduce by binary fission, like bacteria

What evidence supports endosymbiotic theory regarding ribosomes

They contain 70S ribosomes, similar to prokaryotes, not eukaryotic 80S ribosomes

What are the ancestral organisms that likely became mitochondria

Aerobic bacteria

What are the ancestral organisms that likely became chloroplasts

Photosynthetic cyanobacteria

What is apoptosis

Programmed cell death; mitochondria play a key role

What is a thylakoid

Membrane sac in chloroplasts where the light-dependent reactions occur

What is the stroma

The fluid-filled space in chloroplasts where the Calvin cycle happens