Biology Chapter: Cell Transport and Organelles

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of the central vacuole in plant cells?

Photosynthesis

Maintenance of turgor pressure (correct)

Protein synthesis

Storage of genetic material

Which of the following statements is true regarding vacuoles?

Vacuoles serve as storage sites for various substances. (correct)

Vacuoles are found only in animal cells.

Vacuoles contain specialized enzymes for digestion.

Vacuoles are always smaller than vesicles.

What differentiates vacuoles from vesicles?

Vacuoles originate from the endoplasmic reticulum, while vesicles do not.

Vacuoles have no internal structure unlike vesicles.

Vacuoles are smaller than vesicles.

Vacuoles perform more diverse functions than vesicles. (correct)

What type of vacuoles are involved in expelling excess water from protozoa?

Contractile vacuoles Signup and view all the answers

What is the tonoplast?

Membrane surrounding the plant vacuole Signup and view all the answers

What role do contractile vacuoles play in freshwater microorganisms?

They pump out excess water. Signup and view all the answers

What is turgor pressure primarily associated with in plant cells?

The filling of central vacuoles with water. Signup and view all the answers

Which of the following describes active transport?

It involves moving molecules against the concentration gradient. Signup and view all the answers

What process is described by the term endocytosis?

The intake of solids and liquids into the cell. Signup and view all the answers

What is the function of the sodium-potassium pump?

It pumps out 3 sodium for every 2 potassium taken in. Signup and view all the answers

What did the term organelle originally refer to?

Only membranous structures. Signup and view all the answers

How do organelles in a cell operate compared to factory assembly lines?

They function simultaneously to process chemicals. Signup and view all the answers

What does exocytosis accomplish in a cell?

It pushes substances out of the cell. Signup and view all the answers

What does the cell theory state about organisms?

All organisms are composed of one or more cells. Signup and view all the answers

What is the significance of the surface/volume ratio in cells?

It affects the ability to get nutrients and expel wastes. Signup and view all the answers

What is the largest type of cell mentioned in the content?

A frog's egg. Signup and view all the answers

Why are cells typically small in size?

Surface area affects the exchange of materials. Signup and view all the answers

What is the smallest unit of measurement for cell inclusions and macromolecules?

Nanometers (nm) Signup and view all the answers

Which of these statements is false according to cell theory?

Cells can form spontaneously from nutrients. Signup and view all the answers

What is the approximate size of a typical cell relative to a millimeter?

Most cells are far smaller than one millimeter. Signup and view all the answers

Cells are primarily the basic units of which two aspects?

Structure and function. Signup and view all the answers

What are plasmids in prokaryotic cells?

Small accessory rings of DNA Signup and view all the answers

What role do ribosomes play in prokaryotic cells?

Synthesis of proteins Signup and view all the answers

What is the significance of thylakoids in cyanobacteria?

They are involved in photosynthesis Signup and view all the answers

How do prokaryotes compare to human beings in metabolic competence?

Prokaryotes are more metabolically competent than humans Signup and view all the answers

What can prokaryotes synthesize given adequate nutrients?

Any kind of molecule they may need Signup and view all the answers

To what extent can prokaryotes adapt to different environments?

Prokaryotes are adapted to live in almost any kind of environment Signup and view all the answers

What is one way humans exploit the metabolic capabilities of bacteria?

To produce a variety of chemicals and products Signup and view all the answers

What characterizes the cytoplasm of prokaryotic cells?

It is a site of thousands of chemical reactions Signup and view all the answers

What is the diameter of actin filaments?

7 nm Signup and view all the answers

What role do actin filaments play in cellular movement?

They form a dense network under the plasma membrane. Signup and view all the answers

Which type of filaments are classified as having a diameter of 8–11 nm?

Intermediate filaments Signup and view all the answers

What is a key characteristic of intermediate filaments with respect to their structure?

They are ropelike assemblies of fibrous polypeptides. Signup and view all the answers

What allows cells to move in an amoeboid fashion?

Actin filament assembly Signup and view all the answers

What supports the nuclear envelope and the plasma membrane?

Intermediate filaments Signup and view all the answers

What protein is primarily responsible for providing mechanical strength to skin cells?

Keratin Signup and view all the answers

Which structural feature allows both actin and intermediate filaments to be dynamic?

Their ability to assemble and disassemble Signup and view all the answers

Study Notes

Transport Across Cell Membranes

Moving molecules against the concentration gradient is active transport.
Active transport requires energy.
Taking substances into the cell is endocytosis.
Pinocytosis involves taking in water, phagocytosis involves taking in solids.
Pushing substances out of the cell is exocytosis.
Exocytosis is how waste is removed from cells.
The sodium-potassium pump moves 3 sodium ions out of the cell for every 2 potassium ions moved in.

Organelles of Animal and Plant Cells

The term organelle once referred to only membranous structures.
All organelles in a cell function simultaneously.
Organelles process incoming chemicals.

Prokaryotic Cells

Many prokaryotes have small rings of DNA called plasmids.
Prokaryotes have ribosomes for protein synthesis.
Photosynthetic cyanobacteria have flattened disks called thylakoids which contain light-sensitive pigments.
Prokaryotes display a wide variety of metabolic functions.
Prokaryotes live in diverse environments.
Prokaryotes can use almost any organic matter as a nutrient.
Prokaryotes are more metabolically competent than human beings.
Prokaryotes can synthesize any molecule they need given adequate nutrients.
Humans use bacteria to produce products for human use.

Cell Theory

Cells come from pre-existing cells.
All organisms are made up of cells.
Cells are the basic living units in all organisms.

Cell Size

Cells are usually small.
A frog’s egg is visible to the human eye.
Micrometers are used to measure cells.
Nanometers are used to measure cell inclusions and macromolecules.
The surface area to volume ratio of cells is important for nutrient intake and waste removal.

Vacuoles

Vacuoles are large membrane-bound sacs.
Vacuoles are distinguished from vesicles by size.
In plants, algae, and fungi, vacuoles perform many of the roles that lysosomes perform in animals.
The central vacuole is usually a single large sac found in plant cells.
Vacuoles store water, food, salts, pigments, and metabolic wastes;
The vacuole maintains turgor pressure.
The tonoplast is the membrane of the plant vacuole.
Food vacuoles are found in protozoa and some animal cells.
Contractile vacuoles remove excess water.

Microbodies

Microbodies are small membrane-bound organelles.
Microbodies carry out specific cellular functions.

The Cytoskeleton

Actin filaments are thin fibers.
Actin filaments form a network beneath the plasma membrane.
Actin filaments are involved in forming pseudopods.
Intermediate filaments are thicker than actin filaments but thinner than microtubules.
Intermediate filaments support the nuclear envelope and the plasma membrane.
Keratin is an intermediate filament that is important for the strength of skin cells.
Intermediate filaments are dynamic structures.

Studying That Suits You

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

Description

Test your knowledge on cell transport mechanisms, including active transport, endocytosis, and exocytosis. Additionally, explore the characteristics and functionalities of animal and plant cell organelles, as well as prokaryotic cell structures. This quiz will challenge your understanding of cellular processes and organelle functions.