Cell Organelles and Their Functions: Nucleus, ER, Golgi, Lysosomes, Mitochondria, Chloroplasts

What is the function of the nucleus in a cell?

The nucleus contains chromatin, which is a complex of DNA and proteins, and is responsible for synthesizing ribosomal RNA (rRNA) in the nucleolus.

What is chromatin and its role during cell division?

Chromatin is a complex of DNA and proteins that condenses into chromosomes during cell division.

What is the central dogma of molecular biology?

The central dogma states that DNA is transcribed into RNA, which is then translated into proteins.

What are ribosomes and where can they be found?

Ribosomes are composed of rRNA and proteins, and can be found free in the cytosol or bound to the rough endoplasmic reticulum (ER).

What distinguishes rough ER from smooth ER?

Rough ER has ribosomes on its surface and is involved in protein synthesis, while smooth ER lacks ribosomes and is involved in lipid synthesis, detoxification, and calcium storage.

What is the function of the Golgi apparatus?

The Golgi apparatus modifies, sorts, and packages proteins and lipids synthesized in the ER into vesicles for transport.

What are lysosomes and their primary function?

Lysosomes are membrane-bound vesicles containing digestive enzymes that break down macromolecules and old organelles.

What are vacuoles and their roles in cells?

Vacuoles are membrane-bound structures that store substances and help maintain turgor pressure; food vacuoles form through phagocytosis.

What is the primary role of mitochondria?

Mitochondria generate ATP through cellular respiration and have a double membrane structure with distinct compartments.

What is the function of chloroplasts?

Chloroplasts are responsible for photosynthesis and contain thylakoids organized into stacks called grana.

What are peroxisomes and their function?

Peroxisomes are single-membrane organelles involved in redox reactions, including the breakdown of hydrogen peroxide.

What is the significance of the cis and trans faces of the Golgi apparatus?

The cis face receives vesicles from the ER, while the trans face dispatches vesicles to their destinations.

How do lysosomes contribute to cellular recycling?

Lysosomes break down macromolecules and old organelles, facilitating recycling of cellular components.

What is the structure of mitochondria?

Mitochondria have a double membrane with an intermembrane space and a matrix where metabolic processes occur.

What is the fluid surrounding thylakoids in chloroplasts called?

The fluid surrounding thylakoids is called stroma.

What process do food vacuoles undergo?

Food vacuoles are formed through phagocytosis, where the cell engulfs food particles.

Why are peroxisomes considered less understood than other organelles?

Peroxisomes are less understood due to ongoing research into their origins and specific functions.

What is the role of the nucleolus within the nucleus?

The nucleolus synthesizes ribosomal RNA (rRNA), which is essential for ribosome production.

What types of proteins does the rough ER primarily synthesize?

The rough ER primarily synthesizes membrane proteins and glycoproteins.