Anatomy

How does the structure of the cell relate to its function?

How does the structure of the cell relate to its function?

 Building blocks and providing processes that help the organism it makes up stay alive. 

How do the organelles contribute to the function of the cell and the organism as a whole?

They have different functions and each play a part in their role. Nucleus, Mitochondria, Ribosomes, ER, Golgi, and more.

Cytology means

 Branch of Biology concerned with the structure and function of plant and animal cells.

Cells have 3 main parts:

1) Nucleus 

2) Cytoplasm

3) Cell Membrane

 The cell membrane is SELECTIVELY PERMEABLE meaning

controls what enters and leaves the cell

The cell membrane is a double layer of phospholipids with embedded proteins. How does this affect permeability?

The permeability is controlled by the lipid solubility of molecules and the presence of specific proteins that facilitate transport

Sketch the membrane to remember what it looks like.

Sketch it

What is cell differentiation? 

Cells that have developed specialized characeritistcs are said to be differentiated 

How are progenitor cells different from stem cells?

Process of specialization of cells,

Stem cells self-renew, differentiate into many types, and can repair organs.

Progenitor cells are partially differentiated and have limited ability to become other cells.

Cell Membrane: (also called phospholipid bilayer) consists of ______________________ and ______________________ proteins. Explain

Integral, Perpipheal Integral = Embedded within the phospholipid bilayer of the cell membrane. Peripheral proteins = not embedded within the phospholipid bilayer but are attached to the outer or inner surfaces of the membrane.

What is the difference between a semi-permeable and selectively permeable membrane?  Which type do cells have?

• A semipermeable membrane lets particles through based on size.

• A selectively permeable membrane controls what passes through based on factors like charge and chemical properties, not just size. Cells have selectively permeable membranes.
  
  Cells = selectively permeable membranes

Why is cystic fibrosis considered a disorder of the cell membrane?

Cystic fibrosis is considered a disorder of the cell membrane because it is caused by a mutation in the CFTR (cystic fibrosis transmembrane conductance regulator) gene,

CYTOPLASM =

the area between the plasma membrane and nucleus, where most metabolic reactions take place.

ENDOPLASMIC RETICULUM (E.R.) -

1. complex system of canals and channels
   Function = transporting materials throughout the cell, including proteins and lipids.

Rough ER -

where ribosomes are located
Ribosomes make proteins.

Smooth ER -

no ribosomes, where lipid synthesis takes place.

Golgi Apparatus:

• The droplets on the edges of the G.A. are vesicles.

• Function: Modifies, sorts, and packages proteins and lipids for export or delivery within the cell.

• Proteins are exported in: Vesicles.

Mitochondria -

the "powerhouse" of the cell, harvests energy.

Function: Energy from food is converted to ATP (adenosine triphosphate).

This process is called cellular respiration.

Cellular respiration requires glucose (food) and oxygen

Lysosomes:

• Contain enzymes; sometimes called the "digestive system" of the cell.

• Purpose of enzymes: Break down waste, damaged organelles, and cellular debris.

Peroxisomes:

Different from lysosomes as they contain enzymes that detoxify harmful substances (like hydrogen peroxide).

Centrosome (centrioles):

• Composed of 2 "cylinders" which lie perpendicular to each other.

• Involved in cell division.

• During cell division, centrioles form a spindle apparatus.

Cytoskeleton:

Made of microtubules and microfilaments that give the cell support and shape.

Nucleus:

• Directs the activities of a cell.

• Contains genetic information (DNA) in the form of chromatin.

What limits the size of cells?

Surface area to volume ratio and Diffusion rates

DIFFUSION

molecules move from an area of higher concentration to an area of lower concentration.

FACILITATED DIFFUSION

molecules diffuse through a membrane with the help of carrier proteins.

OSMOSIS

the diffusion of water through a selectively permeable membrane.

SOLUTIONS:

• Hypertonic Solution: A solution with a higher concentration of solutes outside the cell than inside, causing water to move out of the cell.

• Hypotonic Solution: A solution with a lower concentration of solutes outside the cell than inside, causing water to move into the cell.

• Isotonic Solution: A solution with equal concentrations of solutes inside and outside the cell, resulting in no net movement of water.

ACTIVE TRANSPORT:

Molecules are moved against the concentration gradient. This requires the use of cellular energy, and usually involves a carrier molecule.

Exocytosis

The process of expelling materials from the cell by fusing a vesicle with the cell membrane.

Endocytosis

The process of taking materials into the cell by forming a vesicle around them.

Pinocytosis:

Liquids are taken in, and the cell engulfs a droplet of water.

Phagocytosis:

Solids are taken in, and a vesicle forms around them.

Where does the energy come from to power this type of transport?

The energy comes from ATP (adenosine triphosphate).

• Interphase:

• Growth phase where chromosomes duplicate and organelles increase in number

• Mitosis:

• Nuclear division.

Cytoplasmic Division:

Also called cytokinesis, the process where the cell splits into two daughter cells.

Differentiation:

Cells become specialized, developing distinct characteristics in structure and function.

Mitosis:

• Prophase: Chromosomes condense and become visible; the nuclear membrane disappears, and spindle fibers form.

• Metaphase: Chromosomes align in the center of the cell (the metaphase plate).

• Anaphase: Sister chromatids are pulled apart toward opposite poles of the cell by the spindle fibers.

• Telophase: Chromatids reach opposite poles, the nuclear membrane reforms, and chromosomes begin to de-condense.

• Cytokinesis: The cytoplasm divides, resulting in two daughter cells.

Differentiation:

The process by which cells become specialized in structure and function.

Cancer:

A disorder where cells lose the ability to control growth and division, leading to uncontrolled cell proliferation.

Apoptosis:

Programmed cell death, a natural process where cells that are no longer needed are eliminated.

HeLa Cells:

A famous line of human cancer cells used in scientific research, derived from Henrietta Lacks.

PH scale =

• pH scale: 0 to 14.

• Less than 7 = Acid.

• 7 = Neutral.

• More than 7 = Base.