The Eukaryotic Cell - Lecture Notes Flashcards

Question-and-answer flashcards covering key concepts from the lecture notes on eukaryotic cells.

Which groups are included in the eukaryotic cell category according to the notes?

Algae, protozoa, fungi, higher plants, and animals.

What is the typical size range of a eukaryotic cell?

About 10–100 μm in diameter (larger than bacteria).

Do eukaryotic cells have standard names for their morphology?

No; there are no standard names for morphology.

Name two major features that differentiate plant cells from animal cells.

Chloroplasts and a cell wall (plant cells also typically have a large central vacuole).

What is the primary function of mitochondria?

To generate ATP; they have their own DNA and ribosomes, supporting the endosymbiotic theory.

What are the two sections of the endoplasmic reticulum and their main roles?

Rough ER (with ribosomes) synthesizes proteins into the lumen; Smooth ER synthesizes phospholipids, fats, and sterols.

What is the Golgi complex and its main function?

The post office of the cell; it modifies, sorts, and packages proteins for transport.

Describe the ribosome types in eukaryotic cells and organelles.

80S ribosomes in the cytosol and on the rough ER (composed of 40S and 60S subunits); mitochondria and chloroplasts use 70S ribosomes.

What are lysosomes?

Membrane-bound organelles with digestive enzymes for breaking down biomolecules; play a role in immune defense.

What are peroxisomes and their role?

Detoxification organelles that oxidize toxic compounds; can produce/convert hydrogen peroxide to water and oxygen.

What is the function of vacuoles?

Membrane-bound storage cavities; variable in size and function; derived from the Golgi.

What are chloroplasts and what features relate to photosynthesis?

Organelles containing chlorophyll and the enzymes for photosynthesis; contain thylakoids in granum; have 70S ribosomes and own DNA.

What is the Endosymbiotic Theory?

A theory that eukaryotic organelles originated from engulfed prokaryotes that became integrated into the host cell.

What evidence supports the Endosymbiotic Theory?

Mitochondria and chloroplasts resemble bacteria in size/shape, have circular DNA, contain 70S ribosomes, and replicate independently; antibiotics can affect them similarly to bacteria.

What are the key features of the nucleus?

A true nucleus with a double membrane (nuclear envelope) containing most genetic material and a nucleolus; DNA associated with histones and organized as chromatin.

What is the nucleolus?

Site of ribosomal RNA (rRNA) synthesis and ribosome assembly.

What is the function of nuclear pores?

Allow selective transport between the nucleus and cytoplasm; enable transcription/translation to be spatially separated.

What is chromatin and its relationship to histones?

DNA bound to histone proteins to form chromatin; condenses DNA and regulates transcription.

What is the cytoplasm?

Everything inside the plasma membrane and outside the nucleus.

What is the cytoskeleton and what is it composed of?

A network of microfilaments, intermediate filaments, and microtubules that maintains shape, organization, and movement.

What are the main features of the plasma membrane in eukaryotic cells?

Phospholipid bilayer with proteins and sterols; carbohydrates on the surface; serves in signaling, adhesion, and selective transport.

What is glycocalyx and its function?

A layer of sticky carbohydrates on the cell surface involved in attachment and cell-cell recognition; some cells also have a pellicle instead (e.g., protozoa).

Do eukaryotic cells contain peptidoglycan?

No; peptidoglycan is absent in eukaryotic cells and is targeted by antibiotics in bacteria.

What types of transport occur across the plasma membrane?

Simple diffusion, facilitated diffusion, active transport, passive transport, and endocytosis.

What are the three types of endocytosis?

Phagocytosis, pinocytosis, and receptor-mediated endocytosis.

What are basal bodies and their role in locomotion?

Structures at the base of flagella and cilia that anchor them and organize the microtubules.

How do prokaryotic and eukaryotic flagella differ?

Prokaryotic flagella rotate; eukaryotic flagella beat in a wave; eukaryotic flagella are about 200 nm in diameter.

What is the difference in number and length between cilia and flagella?

Cilia are short and numerous; flagella are long and fewer in number.

What are the main components of eukaryotic cell walls for plants/algae and fungi?

Plants/algae: cellulose; fungi: chitin (N-acetylglucosamine).

What are the main components of yeast cell walls?

Glucan and mannan.

What covers some eukaryotic cells instead of a cell wall?

Glycocalyx.

What is the Golgi apparatus often described as?

The post office of the cell; it packages and transports proteins via secretory vesicles.

Where are ribosomes located and what are their destinations?

Ribosomes are either free in the cytosol (proteins for the cytosol) or bound to the rough ER (proteins for secretion or membranes).

What special features do mitochondria have that support the endosymbiotic theory?

Circular DNA, 70S ribosomes, and the ability to replicate independently within the cell.

What is the difference between transcription and translation in eukaryotes?

Transcription occurs in the nucleus; translation occurs in the cytoplasm, separated by the nuclear envelope.

What are the inner membrane folds of mitochondria called and their purpose?

Cristae; they increase the surface area for ATP production.

What is the matrix of mitochondria?

The fluid-filled space inside the inner membrane where metabolic reactions occur.