apbio

What is the primary function of the nucleus?

stores genetic dna

What is the function of mitochondria?

breaks down sugars to produce atp

What are ribosomes and what do they do?

responsible for protein synthesis assembling amino acids into proteins.

Differentiate between the functions of the Rough Endoplasmic Reticulum (RER) and the Smooth Endoplasmic Reticulum (SER).

The RER (studded with ribosomes) is involved in the synthesis and modification of proteins destined for secretion or insertion into membranes. The SER is involved in lipid synthesis, detoxification of drugs and poisons, and storage of calcium ions.

What is the primary function of the peroxisomes?

Peroxisomes are involved in diverse metabolic processes, including the breakdown of fatty acids and detoxification of harmful substances, often producing hydrogen peroxide as a byproduct.

What are centrosomes and what do they do?

Centrosomes are the main microtubule-organizing centers in animal cells, crucial for cell division by forming the spindle fibers.

What are centrioles?

Centrioles are small, cylindrical structures located within the centrosome of animal cells, involved in the formation of spindle fibers during cell division.

What are cilia?

Cilia are short, hair-like appendages that project from the surface of eukaryotic cells, involved in cell movement (e.g., moving fluid over surfaces) or acting as sensory organelles.

What are flagella?

Flagella are longer, whip-like appendages that extend from the cell surface, primarily responsible for cell locomotion.

What is the extracellular matrix (ECM)?

The extracellular matrix (ECM) is a complex network of macromolecules (proteins and carbohydrates) secreted by cells, providing structural and biochemical support to the surrounding cells in animal tissues.

What are tight junctions?

Tight junctions are cell junctions that form a watertight seal between adjacent animal cells, preventing the leakage of extracellular fluid across a layer of epithelial tissue.

What are desmosomes?

Desmosomes are anchoring junctions that fasten animal cells together into strong sheets, providing mechanical strength and resisting tearing.

What are gap junctions?

Gap junctions are communicating junctions that provide cytoplasmic channels between adjacent animal cells, allowing for the passage of small molecules and ions for direct cell-to-cell communication.

What are plasmodesmata?

Plasmodesmata are microscopic channels that perforate plant cell walls, connecting the cytoplasm of adjacent plant cells and allowing for the transport of molecules and communication.

Define the endomembrane system.

The endomembrane system is a group of membranes and organelles in eukaryotic cells that work together to modify, package, and transport lipids and proteins. It includes the nuclear envelope, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, and the plasma membrane.

What is the function of the nucleolus?

The nucleolus is a dense region within the nucleus primarily involved in the synthesis of ribosomal RNA (rRNA) and the assembly of ribosomes.

What is the nuclear envelope?

The nuclear envelope is a double membrane that encloses the nucleus of a eukaryotic cell, separating its contents from the cytoplasm.

What are nuclear pores?

Nuclear pores are protein-lined channels within the nuclear envelope that regulate the passage of molecules (e.g., RNA and proteins) between the nucleus and the cytoplasm.

What is the generalized function of vesicles?

Vesicles are small, membrane-bound sacs within the cytoplasm that are involved in storing and transporting substances, as well as in metabolic reactions.

What is cytosol?

Cytosol is the jelly-like substance that fills the cytoplasm of a cell, in which the organelles are suspended and many metabolic reactions take place.

What are cristae in mitochondria?

Cristae are the folds of the inner mitochondrial membrane, which significantly increase the surface area for the chemical reactions of cellular respiration (specifically the electron transport chain and ATP synthesis).

What are thylakoids in chloroplasts?

Thylakoids are flattened, interconnected sacs within chloroplasts where the light-dependent reactions of photosynthesis occur.

What are grana in chloroplasts?

Grana (singular: granum) are stacks of thylakoids within the chloroplast, increasing the surface area for light absorption during photosynthesis.

What is the stroma in chloroplasts?

The stroma is the fluid-filled space surrounding the grana within a chloroplast, where the light-independent reactions (Calvin cycle) of photosynthesis take place.