Cell Biology: Structure of Cilia and Flagella

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which scientist is credited with the observation that plant cells have a unique feature that distinguishes them from animal cells?

Robert Hooke

Matthias Schleiden

Rudolf Virchow

Theodore Schwann (correct)

What significant contribution did Rudolf Virchow make to the understanding of cell theory?

He discovered the plasma membrane.

He stated that new cells arise from pre-existing cells. (correct)

He proposed that all living organisms consist of one type of cell.

He introduced the concept that cells are the basic unit of life.

What did Schleiden and Schwann collectively propose regarding the nature of living organisms?

Cells only exist in multicellular organisms.

New cells are created through spontaneous generation.

All living organisms are composed of cells and products of cells. (correct)

The cell wall is present in all types of cells.

Which of the following statements reflects a limitation of the initial cell theory proposed by Schleiden and Schwann?

It failed to explain how new cells were formed. Signup and view all the answers

Which component is characteristic of plant cells but not animal cells?

Cell wall Signup and view all the answers

What defines a unicellular organism?

Capable of independent existence Signup and view all the answers

Which component is NOT a minimum requirement for a complete cell?

Nucleus Signup and view all the answers

Who first discovered the structure of cork cells?

Robert Hooke Signup and view all the answers

Which statement about viruses is true?

They lack independent living characteristics Signup and view all the answers

What was the contribution of Matthias Schleiden to cell theory?

Observing that all plants are made up of cells Signup and view all the answers

What is the role of cytoplasm in a cell?

Allowing independent living Signup and view all the answers

Who is credited with discovering the nucleus?

Robert Brown Signup and view all the answers

Which of the following statements is false regarding multicellular organisms?

They can perform independent functions Signup and view all the answers

What is the structural arrangement of microtubules in cilia and flagella known as?

9+2 array Signup and view all the answers

What connects the peripheral doublets of microtubules in cilia and flagella?

A-B Linker Signup and view all the answers

Where do both cilia and flagella emerge from in a cell?

Basal body Signup and view all the answers

What is a microbody?

A single membrane bound vesicle Signup and view all the answers

What are the central microtubules in cilia and flagella connected by?

Bridges & central sheath Signup and view all the answers

What type of cells possess structurally different flagella compared to eukaryotic cells?

Prokaryotic bacteria Signup and view all the answers

What is the main component found in the core of cilia and flagella?

Axoneme Signup and view all the answers

Which structure is NOT a component of the axoneme?

Basal body Signup and view all the answers

What is one of the primary functions of the Golgi complex?

Formation of Lysosomes Signup and view all the answers

What describes the cisternae of the Golgi body?

Flat, branched structures with varied numbers Signup and view all the answers

Which of the following is NOT a function of the endoplasmic reticulum?

Cell secretion Signup and view all the answers

What is the primary role of Cytochrome P450 in the smooth endoplasmic reticulum?

Detoxification Signup and view all the answers

What alternative name is used for the Golgi body in plant cells?

Dictyosome Signup and view all the answers

Which process occurs primarily within the Golgi complex?

Chemical modification of macromolecules Signup and view all the answers

Which of the following best describes the zone of exclusion surrounding the Golgi body?

Cytoplasm with fewer or no organelles Signup and view all the answers

What is the sequence of protein transfer from the endoplasmic reticulum to the Golgi body?

Cis face to Trans face Signup and view all the answers

What is the main function of thylakoids in the chloroplast?

Light absorption and photosynthesis Signup and view all the answers

Which characteristic distinguishes the inner membrane of chloroplasts from the outer membrane?

Absence of porin Signup and view all the answers

Why are chloroplasts referred to as semi-autonomous organelles?

They have limited DNA and depend on the nucleus for some protein synthesis. Signup and view all the answers

What is the space inside a thylakoid called?

Lumen Signup and view all the answers

Which of the following statements regarding ribosomes in chloroplasts is true?

Chloroplast ribosomes are 70s type. Signup and view all the answers

What is the primary role of enzymes found in the stroma of chloroplasts?

Synthesize carbohydrates Signup and view all the answers

What is the composition of a quantasome in chloroplasts?

Molecules of various pigments Signup and view all the answers

Which membrane component is more permeable in chloroplasts?

Outer membrane Signup and view all the answers

Study Notes

Structure of Cilia and Flagella

Cilia and flagella are hair-like extensions of the cell membrane, crucial for cell motility.
Eukaryotic flagella differ structurally from prokaryotic flagella.
Both structures are covered by a plasma membrane with a core called the axoneme.
The axoneme is characterized by a 9+2 arrangement: nine doublets of peripheral microtubules and two central microtubules.
Peripheral doublets are interconnected by linkers, and central tubules are connected by radial spokes and enclosed by a central sheath.
Cilia and flagella originate from basal bodies or blepharoplasts.

Microbodies

Microbodies are single membrane-bound vesicles containing various enzymes.

Cell Definition and Types

Cells are the structural and functional units of organisms.
Unicellular organisms are composed of a single cell, while multicellular organisms consist of many cells.

Minimum Requirements for a Cell

Essential components of a complete cell include: cell membrane, cytoplasm, and genetic material.
Unicellular organisms can perform all vital life functions independently.

History of Cell Discovery

First observed dead cells in cork by Robert Hooke.
First living cells discovered by Anton Von Leeuwenhoek.
Nucleus discovered by Robert Brown.

Cell Theory

Formulated by Schleiden and Schwann, stating all living organisms are composed of cells and their products.
Rudolf Virchow enhanced the theory by explaining that all cells arise from pre-existing cells, leading to modern cell theory.

Functions of Endoplasmic Reticulum (ER)

Key functions include protein and lipid synthesis, intracellular transport, mechanical support, and detoxification.
Facilitates formation of nuclear membrane, lysosomes, and microbodies.

Golgi Complex

First observed by Camillo Golgi; also known as lipochondria or dictyosome in plants.
Composed of cisternae (flattened structures), tubules (branched tube-like structures), and vesicles (membrane-bound structures).
Functions in cell secretion, modification of macromolecules, and formation of lysosomes.

Chloroplast Structure and Function

Surrounded by a double membrane: outer membrane is permeable; inner membrane is less permeable.
Contains stroma, which houses thylakoids stacked in grana, and is essential for photosynthesis.
Quantasome consists of pigment molecules within thylakoid membranes, playing a role in light absorption.
Contains circular, GC-rich DNA and 70s ribosomes, indicating a semi-autonomous nature.

Biogenesis of Chloroplasts

Chloroplasts can form from proplastids, indicating their ability to develop from precursor structures.
They are described as semi-autonomous organelles due to their limited DNA and reliance on the cell's main DNA for protein synthesis.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the intricate structures and functions of cilia and flagella in this quiz. Understand the differences between eukaryotic and prokaryotic flagella, as well as the importance of the axoneme's unique arrangement. Test your knowledge of microbodies and the essential characteristics of cells.