Cell Biology Overview

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Questions and Answers

Which statement about cell theory is correct?

All living things consist of a single type of cell.

Cells can form from non-cellular matter.

All cells have different origins, depending on the organism.

Cells are the basic unit of structure in all living organisms. (correct)

What is the primary function of mitochondria in a cell?

To transport substances across the cell membrane.

To generate energy for cellular processes. (correct)

To synthesize DNA and RNA.

To package proteins for secretion.

What is the role of chloroplasts in plant cells?

To provide structural support.

To store genetic material.

To digest proteins.

To convert sunlight into chemical energy. (correct)

Which organelle is responsible for making ribosomes?

Nucleolus Signup and view all the answers

What distinguishes plant cells from animal cells?

Plant cells possess a cell wall. Signup and view all the answers

What is the process of osmosis primarily concerned with?

The movement of solvent molecules. Signup and view all the answers

Which part of the microscope is used to make large adjustments to focus the specimen?

Coarse focus knob Signup and view all the answers

What is meant by concentration in a solution?

The ratio of solute to solvent. Signup and view all the answers

What distinguishes osmosis from diffusion in terms of movement?

Osmosis refers to solvent moving to balance concentration, while diffusion involves any particle. Signup and view all the answers

Which statement best describes a hypertonic solution?

It has a higher concentration of solutes than the cell. Signup and view all the answers

What is the main structural component of the cell membrane?

Phospholipids Signup and view all the answers

Which of the following correctly describes an isotonic solution?

It has the same concentration of solutes as the surrounding environment. Signup and view all the answers

What major advantage do eukaryotic cells have over prokaryotic cells?

Their DNA is protected within a nuclear membrane. Signup and view all the answers

What is true concerning the sizes and complexities of prokaryotic and eukaryotic cells?

Eukaryotic cells are usually larger and more complex. Signup and view all the answers

What happens to a cell placed in a hypotonic solution?

It bursts due to excess water absorption. Signup and view all the answers

Which of the following is a disadvantage of prokaryotic cells?

If the single cell dies, the entire organism dies. Signup and view all the answers

Study Notes

Cell Theory

All living things are composed of one or more cells.
All cells originate from pre-existing cells.
Cells are the fundamental units of structure and function in living organisms.

Organelles

Cell Membrane

Surrounds both plant and animal cells.

Cell Wall

Surrounds plant cells, providing structural support.
Located as an inner layer.

Cytoplasm

Gelatinous substance that holds organelles in place within the cell.

Mitochondria

The "powerhouse" of the cell, responsible for energy production.

Chloroplast

Site of photosynthesis in plant cells.

Vacuole

Stores water and nutrients.

Lysosome

Digests and removes cellular waste.

Ribosome

Synthesizes proteins.

Nucleus

Controls cellular activities.

Nucleolus

Produces ribosomes.

Nuclear Membrane

Encloses the DNA, providing protection.

Nuclear Pores

Allow passage of DNA materials.

Smooth Endoplasmic Reticulum

Synthesizes lipids (fats).

Rough Endoplasmic Reticulum

Studded with ribosomes involved in protein synthesis.

Golgi Apparatus

Processes, packages, and transports proteins throughout the cell.

Organelle Interactions

Organelles work together to maintain cellular functions.

Animal vs. Plant Cells

Plant cells have a cell wall and a large central vacuole that animal cells lack.

Cell Arrangement Differences

Plant cells are often arranged in regular shapes due to the cell wall, while animal cells exhibit more varied shapes.
Vacuoles and cell walls contribute to this differing arrangement.

Microscopy

Microscope Focusing

Use the coarse adjustment knob with the low objective to initially focus.

Microscope Objective Differences

Low objective: 40x magnification
Medium objective: 100x magnification
High objective: 400x magnification

Microscope Importance

Enables visualization of structures invisible to the naked eye, such as bacteria.

Diffusion and Osmosis

Solute

The substance dissolved in a solution.

Solvent

The substance dissolving the solute.

Solution

A mixture formed when a solute dissolves in a solvent.

Concentration

The amount of solute in a given volume of solution.

Diffusion

Passive movement of particles from high to low concentration across a membrane until equilibrium is reached.

Osmosis

The passive movement of water across a selectively permeable membrane to equalize solute concentrations.

Active vs. Passive Transport

Active transport requires energy; passive transport does not.

Distinguishing Diffusion and Osmosis

Osmosis specifically refers to water movement; diffusion encompasses the movement of any particle across a membrane.

Cell Membrane Structure

Composed of a phospholipid bilayer.
Phosphate/glycerol heads are hydrophilic (water-loving).
Fatty acid tails are hydrophobic (water-repelling).

Semi-permeable Membrane

Allows certain molecules to pass through but not others.

Types of Solutions

Isotonic Solution

Same solute concentration compared to inside the cell.

Hypotonic Solution

Lower solute concentration compared to inside the cell.

Hypertonic Solution

Higher solute concentration compared to inside the cell.

Cellular Impact (Based on Solution Type)

Hypotonic solution: Cell swells due to water flowing in.
Hypertonic solution: Cell shrinks due to water flowing out.

Prokaryote vs. Eukaryote

Prokaryotic vs. Eukaryotic Cells

Eukaryotes have a membrane-bound nucleus; prokaryotes do not.

Prokaryotes vs. Eukaryotes (Specific Characteristics)

Prokaryotes tend to be smaller and less complex, while eukaryotes are larger and more intricate.

Prokaryotic vs. Eukaryotic Examples

Eukaryotic Organisms: Animals, humans (often multicellular)
- Prokaryotic Organisms: Bacteria (often single-celled)

Prokaryotic vs. Eukaryotic Advantages/Disadvantages

Prokaryotic: Faster nutrient movement, but unprotected DNA.
Eukaryotic: Protected DNA, but slow nutrient movement.

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Description

This quiz covers the fundamental concepts of cell theory and the various organelles that make up plant and animal cells. Learn about the functions and structures of key components, including the nucleus, mitochondria, and chloroplasts. Test your knowledge of essential cellular processes through this engaging quiz.