Biology- Chapter 4- Cells

Robert Hooke

Discovered cells in a slice of cork with a microscope

Named them cells after the rooms in his monastery

Thought they were only in plants and fungi at the time

Anton van Leeuwenhoek

Discovered protists and bacteria cells

Called them “animalcules“

Matthias Schleiden and Theodor Schwann

Declared the basic unit in living things is cells

Discovered all plants and animals have cells

Rudolf Virchow

Declared all cells come from other living cells

1. All living things are composed of one or more cells

2. Cells are an organism’s most basic unit of structure and function

3. Cells can only be created from pre-existing cells

The cell theory states…

Prokaryotic and Eukaryotic

Two types of cell

do not store their genetic information in a nucleus

Genetic information is stored in the cytoplasm

very basic cells (unicellular)

Bacteria cells

Prokaryotic cells

Contain a nucleus

Genetic information stored in Nucleus

Other organelles are bound by membranes

Can be unicellular or multicellular

Plant and Animal cells

Eukaryotic cells

Organized or specialized structures in a cell; like mini organs

Organelle-

group of organs that work together to perform a specific function

Organ System-

Protective barrier that is semi permeable, controls what goes in and out of the cell

Cell membrane-

Control center of the cell and controls the functions within the cell, contains the genetic information

Nucleus-

threadlike structures made of DNA molecules that contain and display genetic information

Chromosomes-

Only in plants, give structure and support to the cell, not a gate, its a wall

Cell Wall

only plants, uses light energy to make food

Chloroplast-

Stores food, water, and waste products (allows plants to support heavy objects)

Vacuole

Converts food energy into usable energy for the cell

Mitochondria-

Makes proteins

Ribosomes

Gel-like substance that fills the cell, helps move nutrients in a cell and helps shape the cell

Cytoplasm-

Disposes of waste products, invading molecules, etc.

Lysosome-

Receives, processes, and packages molecules around and out of the cell

Golgi Bodies-

Rough ER- assists in making proteins

Smooth ER- makes lipids

Endoplasmic Reticulum

Pulls apart chromosomes and assists in cell movement

Microtubules-

Tough flexible framework that makes up the cell, assists in cell movement

Microfiliaments-

Make up the majority of the membrane (Phospholipid Bilayer)

The lipids in the cell membrane…

hydrophilic, water loving

The head of a lipid is

hydrophobic, water hating

The tail of a lipid is

are large masses that act as a channel and control what goes in/out

Proteins in the cell membrane…

Little chains on the surface of the cell membrane that help with cell communication

Carbohydrates in the cell membrane…

membranes that allow some substances through but not others

Semi Permeable-

Concentration of specific molecules inside and outside of a cell

Concentration Gradient-

High to low- with the gradient

Low to high- against the gradient

What is the flow of the concentration gradient?

1 type, requires energy, goes against the gradient (low to high)

Active Transport-

diffusion, osmosis, facilitated diffusion

Passive Transport types

3 types, does not require energy, moves with the gradient (high to low)

Passive transport

Diffusion

Movement of SMALL molecules from an area of higher concentration to an area of lower concentration that results in an equilibrium

Facilitated Diffusion

Movement of LARGE molecules from an area of high concentration to low concentration, uses protein channels, results in equilibrium

Osmosis

movement of water across the cell membrane, solvents not solutes crossing the membrane, aims to even the ratio of solvents to solutes out

Hypotonic solution

More solvents than solutes (ex: more water than salt), the cell swells and might burst

Hypertonic

Is this a Hypotonic, Hypertonic, or Isotonic solution

Hypotonic

Is this a Hypotonic, Hypertonic, or Isotonic solution

Isotonic

Is this a Hypotonic, Hypertonic, or Isotonic solution

Hypertonic Solution

More solutes than solvents (ex: more salt than water), the cell shrivels

Isotonic solution

Equal solutes and solvents, cell remains the same

Solution concentration equation

mass of solute (thing being dissolved) divided by mass of solvent (thing doing the dissolving)

the faster the diffusion 

The more surface area in a cell…

the slower the diffusion

The more volume in a cell…

Small cells

What size cell is more effecient?

Size, growth, and to replace other cells

Why does a cell divide?

The process of cell division and growth that cells undergo

Define cell cycle

cyclin

What protein regulates the cell cycle?

replicate (duplicate) its DNA

In order for a cell to fully divide and function it must

chromosomes

Where is DNA located

Carry the DNA and transfer genetic information

What is the main function of chromosomes

interphase, mitosis, cytokinesis

Stages of the Cell Cycle

G1, Synthesis, G2

Stages of Interphase

Interphase

Most of a cell's life is spent in which stage?

G1

Most cell growth occurs during this stage

Synthesis

Cell duplicates DNA

G2

Cell finishes growth and prepares to divide

Prophase, Metaphase, Anaphase, Telophase

Stages of Mitosis

Spindle fibers form, nuclear envelope disappears, Prepares to divide.

Prophase-

Duplicated chromosomes line up in the middle of the cell, spindle fibers connect in the middle of the chromosome pair by a centromre

Metaphase-

Chromosomes are pulled apart by spindle fibers, separated into two identical chromatids

Anaphase-

2 new nuclei are formed, spindle fibers disappear

Telophase-

Full division of one cell into two

Cytokinesis

Energy, space, and pre-existing DNA

What must a cell have in order to divide?

Cancer occurs when cells divide uncontrollably and become cancer cells

What is Cancer?

Unorganized, unusual looking large or multiple nuclei

What do cancer cells look like?

UV exposure, Genetics, diet, radiation, viruses, etc.

What are risk factors for cancer?

It can spread to the rest of the body and potentially kill an organism

What happens when cancer is left untreated

What are the treatment options for cancer

Surgery, radiation, chemotherapy, various therapies