Module 3 - Cells

What is the supportive network of protein rods and tubules in the cytoplasm of a cell?

Cytoskeleton

During prophase, the structures called ________ begin to form microtubules called spindle fibers.

centrioles

Ion _________ are protein structures that permit ions such as calcium, sodium, potassium, or chloride to cross the membrane.

channels

__________ functions to stabilize the cell membrane, increase the hydrophobicity of the interior of the cell membrane, and plays a role in the flexibility of the membrane.

cholesterol

The material in the nucleus called __________ is composed of protein and DNA; it contains information to guide synthesis of proteins and it condenses into chromosomes during cell division.

chromatin

The molecules within the cell membrane that function in cell recognition are the _________.

glycoprotiens

During interphase, in G1 and G2, cells _______.

growth and synthesize organelles

The cell membrane becomes _______ permeable to water-solube substances due to the presence of cholesterol molecules.

less

Hormones like estrogen are lipophilic. This means that they will be ________ - soluble and pass through the cell membrane.

lipid

Active transport is a process that moves particles through a membrane from a region of _______ concentration to a region of ______ concentration.

low;higher

In the cell membrane ____________function as receptors, cell surface markers, tranporterts, channels, enzymes, and cellular adhesion molecules.

proteins

A _________ protein is a type protein that binds to specific molecules, such as hormones, and triggers responses from within the cell.

receptor

On the extracellular surface of the cell membrane, a _____ binds molecules, initiating changes in the cell.

receptor

Cytoplasm contains protein rods and tubules that for a structural framework called the _________

Cytoskeleton

Structures with their functions

*Produces ATP - Mitochondria *Helps in protein synthesis - Ribosomes *Contains most of the DNA - Nucleus *Provides a framework for the cell - Cytoskeleton *Packaged proteins for transport - Golgi apparatus

Three functions of proteins in the cell membrane

- Adhere adjacent cells to each other - Receptors to bind to chemicals - Channels for ions to move through

The stages of Mitosis in order from beginning of the process at the top.

1) Prophase 2) Metaphase 3) Anaphase 4) Telophase

Order of the event that occurred during phagocytosis stating at the beginning at the top.

1. An engulfed particle is enclosed within a vesicle 2. A vesicle detaches from the cell's surface and moves into the cell's interior. 3. Vecsile-lysosomal enzymes decompose vesicle contents 4.Digestive lysosomal enzymes decompose vesicle contents 5. Products of intracellular digestion diffuse into the cytoplasm 6. Residues are expelled outside through exocytosis

________ functions to stabilize the cell membrane, increase the hydrophobicity of the interior of the cell membrane, and plays a role in the flexibility of the membrane.

Cholesterol

The components of the cell membrane

Cholesterol, Phospholipids, Carbohydrates, proteins

How many chromosomes are in each new cell after mitotic divisions?

2 sets of 23 chromosomes and 46 chromosomes.

A cholesterol molecule (within a low density lipoprotein) bind to a receptor; the membrane indents and forms a vesicle that fuses with a lysosome; enzymes digest the lipoprotein and release cholesterol inside the cell for cellular use.

????

The difference between active and passive transport is that active mechanisms use ________.

ATP

What are the forces that drive active transport?

ATP; Cellular energy

What type of protein molecules, due to their role in guiding cell-to-cell interactions, help guide which blood cells to an area of injured tissue?

Cellular adhesion molecules

The nucleus contains ________, which directs all cell activities.

DNA

The type of active transport mechanism in which large molecules or particles are conveyed by a vesicle into the cell is known as ________.

Endocytosis

The movement of glucose through a cell membrane using a carrier is an example of what process?

Facilitated diffusion

The process that involves membrane protein carries to transport glucose or amino acids across the cell membrane down a concentration gradient is called _____________ _____________.

Facilitated diffusion

Both facilitated diffusion and simple diffusion require no carrier to move molecules across the membrane. TRUE OR FALSE

False

When molecules move down the concentration gradient, it means that there is a net movement of particles from a region of lower concentration to a region of higher concentration.

False

Cholesterol enters cells via pinocytosis

False! it enters via pinocytosis

What transport mechanisms are classified as passive mechanisms?

Filtration, Osmosis, Facilitrated Diffusion, and Diffusion

Indicate sub-phases of interphase

G1; S

What is the term given to the difference in concentration of particles from one area to another.

Gradient

increase rate of diffusion

Higher temperature, shorts distance, larger concentration gradient

What part of each phospholipid molecule in the cell membrane comes in contact with the extracellular fluid?

Hydrophilic phosphate head

Concerning DNA, what is the difference between interphase and mitosis

Interphase is when DNA is duplicated and mitosis is when DNA is divided

What are the characteristics of chromatin?

Is made of protein and DNA and Condenses into chromosomes during cell division

What are the characteristics of the nucleus?

It contains the genetic material (DNA)

The characteristics of receptor-mediated endocytosis?

It requires receptors that combine with ligands and it is a type of active transport mechanism

______________ is the name the transport mechanism in which water molecules move through a selectively permeable membrane toward the solution with more impermeant solute (one that cannot cross the membrane)

Osmosis

A white blood cell engulfing a bacterial cell is an example of what process?

Phagocytosis

The type of endocytosis in which a cell membrane engulfs solid particles from its surroundings is called __________

Phagocytosis

The cell membrane is composed mostly of a bilayer of _________.

Phospholipid

Potassium is at a lower concentration outside the cell compared to the inside the cell, and the cell membrane is permeable to the potassium so which way will potassium molecules move?

Potassium will move from inside the cell to the outside the cell

A ligand binds to a receptor on a cell membrane and the cell membrane indents and forms a vesicle. What is this process called?

Receptor-mediated endocyrosis

DNA replication occurs during the _______ phase of interphase.

S

What are the characteristics of nuclear evelope?

Separates the nuclear contents from the cytoplasm and is a double-layered porous membrane

Decrease rate of diffusion

Smaller concentration gradient, large distance, lower temperature.

Components of Glycoprotiens

The contain peripheral proteins and carbohydrate groups

Which of the following is an example of simple diffusion?

The exchange of oxygen and carbon dioxide between the air in the lungs and the blood.

What is cytosol?

The liquid part of the cytoplasm

Which cell structure acts as a selectively permeable barrier, controlling the movement of substances into and out of the cell.

The plasma membrane

What is true of peripheral proteins?

They do not span the entire membrane; they project from the cell surface

Peripheral proteins may work as enzymes or as part of signal transduction pathways.

True

The cell membrane is not simply a boundary, but an actively functioning part of the cell. It is the site of important metabolic reactions and it also enables communication and interaction with other cells. True or False

True

What type of molecule should be able to pass through the cell membrane most easily?

a small, hydrophobic molecule

Interphase is a(n) ________ phase in the cell cycle

active

The source of energy for ________ transport mechanisms is cellular energy.

active

Components of the cellular structure called the ______ include phospholipids, carbohydrates, proteins and cholesterol.

cell membrane

Cytoplasmic division also called ________, is a process that begins during anaphase and continues through telophase. A contractile ring forms around the middle of the cell, eventually pinching the cell into two new cells with identical numbers of chromosomes.

cytokinesis

The process that divides the cytoplasm of a cell into two daughter cells is called __________.

cytokinesis

The three main stages of the cell cycle are interphase, mitosis, and ________.

cytokinesis

The three major parts of a cell the nucleus, __________, and cell membrane.

cytoplasm

Simple ________ occurs due to the random movement of atoms, molecules, or ions in air or liquid, from areas of higher concentration.

diffusion

Diffusional ______ occurs when the concentration of a given substance becomes uniform throughout a solution and there is no further net movement throughout the solution.

equilibrum

Some cells make substances and secrete them by the process of ___________.

exocytosis

What is the structure that buds off of one cell, then travels to and merges with another cell?

exosomes

The passive transports mechanism in which molecules or ions move via carrier proteins from a region of higher concentration to a region of lower concentration is called _________.

facilitated diffusion

In filtration, a solution is pushed through a membrane by a force called ________. This is a(n) ______ transport mechanism.

hydrostatic pressure; passive

A(n) _________ protein is a type of compact or globular protein that spans the cell membrane.

integral

The active period of the cell cycle, during which a cell grows, DNA replicates, and new organelles form, is called ___________. It terminates when the cell begins mitosis.

interphase

The phase that begins after cytokinesis and ends at prophase is called ___________.

interphase

The segment of the cell cycle called ________ is subdivided into the G1 phase, S phase and G2 phase.

interphase

DNA replicates during ______ but is distributed between two daughter cells during _________.

interphase; mitosis

After a particle has been phagocytized, the vesicle in which it is contained fuses with a ________ which will then break down the particle into smaller components.

lysosome

In somatic cell division, the nucleus undergoes a 4-stage process of ________.

mitosis

The ________ envelope is the double membrane that maintains the integrity of the nucleus and contains pores that control the passage of materials between the nucleus and the cytoplasm

nuclear

A(n) __________ is specialized structure inside a cell that performs specific functions such as extracting energy from nutrients or building proteins.

organelle

What is a specialized structure inside a cell called?

organelle

facilitated diffusion is a type of ___________ transport because it moves substances from areas of high concentration to areas of low concentration.

passive

Diffusion of a substance across a membrane can happen only if the membrane is _______ to that substance and a concentration gradient _______ across the membrane.

permeable; exists

Each phospholipid molecule has a water-soluble _________ the points outwards and water-insoluble __________ that makes up the middle of the membrane.

phosphate group; fatty acid tails

The nuclear envelope is perforated with openings called nuclear _________.

pores

Certain membrane proteins work as _______ which admit water molecules, while others work as ______, which admit small molecules or ions.

pores; channels

The cell membrane is _______ permeable.

selectively

Due to the phospholipid bilayer, the cell membrane is ________.

soft and flexible

Meiosis occurs in _________ cells and produces ________ daughter cells.

sperm and egg; four

Within the structure of a cell membrane, the phospholipid heads face ________, while the tails face ______.

the cytosol and extracellular fluid; each other

Within the structure of a cell membrane, the phospholipid heads face __________, while the tails face ________.

the cytosol and extracellular fluid; each other

In the type of active transport called _______, a substance or particle crosses a cell, combing endocytosis and exocytosis to rapidly ferry the particle through or across a cell.

transcytosis

Exocytosis uses ______ to move substances _______ the cell.

vesicles; out of