Cell Biology Basics

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Questions and Answers

What is the primary function of squamous cells?

Support and protection

Diffusion (correct)

Absorption

Production of hormones

What is the main function of Golgi bodies in the cell?

Storing materials and conducting digestion

Producing ATP energy

Facilitating cell division

Modifying and packaging proteins and lipids (correct)

Which location is NOT associated with squamous cells?

Bone marrow (correct)

Air sacs

Lining of heart

Kidney

Which of the following statements best describes mitochondria?

They are the powerhouse of the cell producing ATP. Signup and view all the answers

What is the shape of cuboidal cells?

Dice-shaped Signup and view all the answers

Which function is primarily associated with columnar cells?

Absorption and secretion Signup and view all the answers

What role do lysosomes play in a cell?

Digestion and waste disposal Signup and view all the answers

Where are ciliated columnar cells predominantly found?

Nose and fallopian tubes Signup and view all the answers

Which type of plastid is responsible for the green pigment in plants?

Chloroplastids Signup and view all the answers

What is the function of the vacuole in a cell?

Storing materials and maintaining pressure Signup and view all the answers

What is the primary role of bone tissue?

Support and hematopoiesis Signup and view all the answers

What characteristic distinguishes fibro cartilage?

Absorbs compressive shock Signup and view all the answers

What is the primary role of the nucleus in eukaryotic cells?

To store the genetic material and facilitate transcription Signup and view all the answers

What structure do centrioles form when paired together?

Centrosome Signup and view all the answers

What defines prokaryotes in comparison to eukaryotes?

Prokaryotes lack a true nucleus and are typically single-celled. Signup and view all the answers

Which component of the cytoskeleton is responsible for maintaining cell shape?

Microfilaments Signup and view all the answers

What type of matrix do elastic cartilage cells have?

Elastic fibers Signup and view all the answers

What is the primary role of the glycoalyx in animal cells?

Cell recognition and adhesion Signup and view all the answers

What is the function of the endoplasmic reticulum?

To transport substances and synthesize proteins and lipids Signup and view all the answers

Which of the following correctly distinguishes between rough ER and smooth ER?

Rough ER has ribosomes on its surface, Smooth ER does not. Signup and view all the answers

What is cytoplasm primarily composed of?

Fluid matrix and organelles Signup and view all the answers

Which part of the nucleus is known as the site of ribosome biogenesis?

Nucleolus Signup and view all the answers

What is the function of the cytoskeleton in a cell?

To support and maintain cell shape Signup and view all the answers

Which of the following best describes a semi-permeable membrane?

A barrier that selectively allows certain materials to pass Signup and view all the answers

What is the primary role of chondrocytes in the body?

Producing collagen and maintaining cartilage. Signup and view all the answers

How do fibroblasts contribute to tissue maintenance?

By secreting collagen proteins. Signup and view all the answers

What adaptation allows muscle cells to perform their function effectively?

Ability to contract and relax. Signup and view all the answers

What is a key characteristic of fat cells that aids in their energy storage function?

They can expand to store more fat. Signup and view all the answers

What is the primary function of ciliated cells in the airways?

To move mucus and dust out of the airways. Signup and view all the answers

Which of the following is NOT a function of epithelial tissue?

Energy storage. Signup and view all the answers

Which type of epithelial tissue is classified based on the number of cell layers?

Simple, stratified, pseudostratified. Signup and view all the answers

What structural feature is characteristic of ciliated cells?

Presence of tiny hairs called cilia. Signup and view all the answers

What is the primary function of areolar cartilage?

Supports and conveys tissue fluid Signup and view all the answers

Which specialized cell is primarily associated with adipose tissue?

Adipocytes Signup and view all the answers

What type of matrix is found in cartilage tissue?

Rubbery matrix with collagen and chondroitin Signup and view all the answers

Which type of muscle tissue is involuntary and striated?

Cardiac muscle Signup and view all the answers

What are the two main properties of neurons?

Irritability and conductivity Signup and view all the answers

Which of the following is NOT a characteristic of skeletal muscle cells?

Single nucleus Signup and view all the answers

What type of cells in nervous tissue provide support and nourishment to neurons?

Neuroglia Signup and view all the answers

What function does the matrix serve in areolar tissue?

Holds organs in place Signup and view all the answers

Study Notes

Cell Theory

The cell, from the Latin "cella" meaning "small room," is the fundamental structural, functional, and biological unit of all known organisms.
It's the smallest unit of life, often called the "building blocks of life."
A semi-permeable membrane allows only certain materials to pass through under specific conditions.

Cytoplasm

The fluid portion of the cell containing the cytoskeleton, organelles, and inclusions.
Also known as the "soup" of the cell.

Cytoskeleton

A network of protein filaments (microtubules, microfilaments) providing support and maintaining cell shape.
Acts as the framework of the cytoplasm, aiding organelle movement.

Nucleus

A membrane-bound organelle containing the genetic material (DNA) of eukaryotic organisms.
Maintains cell integrity by facilitating transcription and replication.
The largest organelle, occupying about a tenth of the cell's volume.

Parts of the Nucleus

Nuclear Envelope: A membrane separating the nucleus from the cytoplasm.
Nucleoplasm: A protoplasm composed of water, molecules, and dissolved ions.
Nucleolus: The site of ribosome biogenesis.

Cytoplasmic Organelles

Endoplasmic Reticulum (ER)

A network of flattened sacs and tubes extending from the nuclear membrane to the plasma membrane.
Transports substances and synthesizes lipids, enzymes, and proteins.
Rough ER: Has ribosomes on its surface.
Smooth ER: Lacks ribosomes.

Ribosomes

Sites of protein synthesis.
Found attached to rough ER or free in the cytosol.
Produced in the nucleolus.

Golgi Bodies

Flattened membrane stacks that modify and package proteins and lipids into vesicles.
A vesicle is a self-contained structure with fluid or gas enclosed by a lipid bilayer.

Mitochondria

The "powerhouse" of the cell, producing ATP (adenosine triphosphate).

Vacuole

A single-membrane sac involved in storage, waste release, intracellular digestion, and maintaining hydrostatic pressure.

Lysosomes

Small, membrane-bound structures containing enzymes for cellular digestion.
The "garbage disposal" of the cell.

Glycocalyx

The cell coat on the outer part of animal cells; involved in cell recognition and adhesion.

Plastids (Plant Cells)

Large, disk-shaped organelles containing pigments.
Found only in plant cells and some photosynthetic protists.
Chloroplasts: Contain green pigment.
Chromoplasts: Contain red, yellow, and orange pigments.
Leucoplasts: Lack color.

Centrosome

The main microtubule organizing center.
Regulates the cell division cycle.

Centriole

A cylindrical organelle composed mainly of tubulin.
Found in most eukaryotic cells.
A centrosome contains a pair of centrioles surrounded by pericentriolar material.

Prokaryotes vs. Eukaryotes

Prokaryotes

"Before the nucleus."
Single-celled organisms, the smallest and most metabolically diverse life forms.

Eukaryotes

Organisms with free-living cells (capable of independent existence) or trillions of cells working together.
Contain visible organelles and a true nucleus.

Specialized Animal Cells & Adaptations

Osteoclasts: Dissolve old bone tissue for replacement.
Chondrocytes: Produce collagen and extracellular matrix for cartilage maintenance.
Fibroblasts: Secrete collagen for tissue framework.
Muscle cells: Contract and relax; found in cardiac, skeletal, and smooth muscle.
Fat cells: Store energy as fat; expand to store more fat; have few mitochondria; act as padding.
Ciliated cells: Move mucus and other substances; have cilia that beat rhythmically.

Cell Types & Tissues (Animals)

Cells form tissues, which fulfil similar functions.
Four basic animal tissue types: epithelial, connective, muscle, and nervous.

Epithelial Tissue

Covers body surfaces (internal and external).
Functions: protection, absorption, secretion, sensory reception.
Classified by cell layer number (simple, stratified, pseudostratified) and cell shape (squamous, cuboidal, columnar).

Epithelial Cell Types Based on Shape

Squamous: Thin, scaly; diffusion, filtration, secretion, protection (kidneys, air sacs, heart lining).
Cuboidal: Dice-shaped; secretion, absorption (kidney tubules, egg cells, glands).
Columnar: Taller than wide; absorption, secretion, sensory reception (digestive tubes, gallbladder, uterus).
Ciliated Columnar: Have cilia; move mucus (nose, uterus).
Pseudostratified Columnar: False stratification; filtration, absorption, secretion (ducts, trachea).

Connective Tissue

Connects, binds, supports body parts.
Highly vascularized; contains cells and a matrix (ground substance and fibers).

Connective Tissue Types

Bone: Support, protection, leverage, storage, hematopoiesis (osteocytes, hard matrix).
Hyaline Cartilage: Support, cushioning (chondrocytes, firm matrix).
Fibrocartilage: Shock absorption (chondrocytes, collagenous matrix).
Elastic Cartilage: Support (chondrocytes, elastic matrix).
Areolar Tissue: Holds and conveys tissue fluid; inflammation (mast cells, white blood cells, fibroblasts, macrophages, gel-like matrix).
Adipose Tissue: Lipid storage (adipocytes, reticular matrix).
Cartilage Tissue: Support, structure (chondrocytes, rubbery matrix).
Areolar Tissue: Holds organs (fibroblasts, collagenous, elastic matrix).

Muscle Tissue

Composed of muscle cells that contract.
Contains sarcoplasm (cell membrane), sarcolemma (cytoplasm), and nuclei.

Muscle Tissue Types

Striated/Voluntary/Skeletal: Long, cylindrical; many nuclei, striations (skeletal muscles).
Striated/Involuntary/Cardiac: Short, branching; few striations, one or two nuclei (heart).
Non-striated/Involuntary/Smooth: Spindle-shaped; one nucleus, no striations (visceral muscles).

Nervous Tissue

Contains neurons (conducting cells) and neuroglia (supportive cells).
Neurons have irritability (respond to stimuli) and conductivity (transmit impulses).
Neuron parts: cell body (soma) containing the nucleus and processes.

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Description

Explore fundamental concepts of cell biology including cell theory, cytoplasm, cytoskeleton, and the nucleus. This quiz will test your understanding of the major components that make up living organisms. Delve into the essential building blocks of life and their functions.