BIO 1010 Chapter 4 Flashcards

Flashcards covering the fundamentals of cell biology, including cell theory, prokaryotic and eukaryotic structures, organelles, and the endomembrane system.

What are the smallest basic units of life?

Cells

Where do all life functions happen in an organism?

Inside cells

What are primitive cells called?

Prokaryotic cells

What are more advanced cells with organelles called?

Eukaryotic cells

List the three domains of life.

Bacteria, Archaea, and Eukarya

Which two domains are categorized as prokaryotic?

Bacteria and Archaea

Which domain is categorized as eukaryotic?

Eukarya

What is the first part of the cell theory?

All living things are made of cells.

What is the second part of the cell theory?

Cells are the basic unit of structure and function in living things.

What is the third part of the cell theory?

All cells come from pre-existing cells.

What is the function of the plasma membrane in prokaryotic cells?

Controls what enters and leaves the cell.

What is the function of the cell wall in prokaryotic cells?

Protects the cell and gives it shape.

How is the glycocalyx or capsule described?

A sticky outer coating

What are the two functions of the glycocalyx?

Protects the cell and helps it attach to surfaces.

What is the role of the cytoplasm in a prokaryote?

Internal fluid where many chemical reactions happen.

What is the site of protein synthesis in a cell?

Ribosome

What is the specific job of a ribosome?

Makes proteins

In a prokaryotic cell, where is the DNA located?

Nucleoid region

What is the long whip-like tail used by prokaryotes for movement?

Flagella

What are short hair-like structures used for attachment in prokaryotes?

Pili

Do prokaryotic cells contain membrane-bound organelles?

No

Do eukaryotic cells contain membrane-bound organelles?

Yes

What is the main advantage of having organelles?

They separate cell jobs into compartments, making the cell more efficient and organized.

What physically separates the compartments created by organelles?

A membrane

In general, how would you describe the size of cells?

Small

Why is a small size beneficial for a cell?

Small cells have a higher surface area-to-volume ratio.

How does a high surface area-to-volume ratio affect cell function?

It allows the cell to move nutrients, gases, and waste in and out faster.

What is the definition of the cytosol?

The fluid portion of the cytoplasm inside the cell.

What happens within the cytosol?

Many chemical reactions happen and organelles are suspended.

What is the primary job of the cytoskeleton?

It gives the cell shape, support, organization, and helps with movement.

What are microfilaments made of?

Actin

List three jobs of microfilaments.

Cell movement, muscle contraction, and cell shape.

What are the functions of intermediate filaments?

Give strength, support, and help anchor organelles.

How are microtubules physically structured?

Hollow tubes

Name three roles of microtubules.

Act as tracks, move chromosomes, and form cilia/flagella.

What is the general function of cilia and flagella?

Help cells move or move fluid/materials across the cell surface.

What specific protein makes up both flagella and cilia?

Microtubules

How do cilia compare to flagella in terms of length and number?

Cilia are short and usually many.

How do flagella compare to cilia in terms of length and number?

Flagella are longer and usually one or a few.

What math organization describes the microtubules in cilia and flagella?

$9 + 2$ organization

Which molecule is contained within the nucleus?

The DNA molecule

What is the nuclear envelope?

A double membrane surrounding the nucleus.

What is the function of a nuclear pore?

Opening that controls what enters and leaves the nucleus.

What is the nuclear matrix?

Internal protein framework that supports the nucleus.

What is the function of the nucleolus?

Makes ribosomes/ribosomal RNA.

How is chromatin defined?

Loose, uncondensed DNA wrapped around proteins inside the nucleus.

What specific proteins does DNA wrap around?

Histones

What structures are formed from DNA wrapping around histones?

Nucleosomes

List the components of the endomembrane system.

Nuclear envelope, rough ER, smooth ER, Golgi apparatus, vesicles, lysosomes, and plasma membrane.

What characterizes the appearance of the Rough ER?

It has ribosomes.

What are the functions of the Rough ER?

Modifies and folds proteins.

How does the Smooth ER look compared to the Rough ER?

It has no ribosomes.

What is the primary substance made by the Smooth ER?

Lipids

Besides lipid synthesis, what are two other jobs of the Smooth ER?

Detoxifies chemicals and stores calcium.

How do ribosomes build proteins?

By linking amino acids together.

Where in the cell can ribosomes be located free-floating?

In the cytoplasm/cytosol.

Where are ribosomes found when they are not free-floating?

Attached to the rough ER.

What are the functions of the Golgi apparatus?

Modifies, sorts, and packages proteins and lipids for transport.

What specific structures assist the Golgi apparatus with transport?

Vesicles

What is the function of a lysosome?

Digests old cell parts, food particles, and waste.

What is the nickname for the lysosome?

The cell’s "trash truck"

What is the general function of a peroxisome?

Breaks down toxic substances and hydrogen peroxide into safer products.

Into which specific products does a peroxisome break down hydrogen peroxide?

Water and oxygen ($H_2O$ and $O_2$)

What is the job of the plasma membrane?

Controls what enters and leaves the cell and helps separate the inside from the outside environment.

What is the main molecule found in the plasma membrane?

Phospholipids

What is the primary job of the mitochondria?

Mitochondria make $ATP$.

What is $ATP$?

The usable energy for the cell.

What type of membrane surrounds the mitochondria?

A double membrane

From what do scientists believe mitochondria evolved?

Free-living bacteria

What does the serial endosymbiosis theory state?

Mitochondria and chloroplasts were once free-living bacteria that were engulfed by a larger cell and became organelles.

What are two pieces of evidence for the serial endosymbiosis theory regarding DNA and division?

They have their own DNA and ribosomes and divide like bacteria.

What is one piece of evidence for endosymbiosis regarding external structure?

They have double membranes.

Which two organelles were created through the process of endosymbiosis?

Mitochondria and chloroplasts

What is the function of the chloroplast?

Site of photosynthesis.

How does a chloroplast produce sugars?

By using sunlight.

What is the role of the central vacuole in a plant cell?

Stores water/materials and helps maintain plant cell pressure.

What are the functions of the plant cell wall?

Provides support, protection, and shape.

True or False: Prokaryotic cells have a nucleoid region instead of a nucleus.

True

Which protein found in microfilaments helps with muscle contraction?

Actin

What are the hollow tracks used to move chromosomes during cell division?

Microtubules

What structure facilitates the entry and exit of materials in and out of the nucleus?

Nuclear pore

What is the loose form of DNA found in the nucleus called?

Chromatin

Which organelle is responsible for detoxifying chemicals?

Smooth ER

Where is ribosomal RNA (rRNA) produced?

Nucleolus

Which component of the endomembrane system packages materials in vesicles?

Golgi apparatus

What organelle would be most active in breaking down old cell parts?

Lysosome

What molecule results from the breakdown of hydrogen peroxide in peroxisomes?

$$H_2O$$

The usable energy $ATP$ is primarily produced by which organelle?

Mitochondria

What theory explains the origin of chloroplasts?

Serial endosymbiosis theory

What is the site of photosynthesis in plants?

Chloroplast

Which plant structure helps maintain cellular pressure?

Central vacuole

How many domains in the three-domain system are prokaryotic?

$$2$$

What does '9 + 2' refer to?

The organization of microtubules in cilia and flagella.

Which organelle modification involves folding proteins?

Rough ER

What type of membrane is found in the endomembrane system?

Single or double membranes (like the nuclear envelope).

What structure protects a prokaryote and maintains its shape?

Cell wall

What is the fluid where chemical reactions happen in a prokaryote?

Cytoplasm

What is the role of the nuclear matrix?

It acts as an internal protein framework to support the nucleus.

What organelle makes lipids and stores calcium?

Smooth ER

What allows eukaryotic cells to be more organized than prokaryotic cells?

Organelles (compartmentalization)