Biology unit 5 the cell

Endosymbioctic theory

Eventually, larger cells engulfed these ancestral chloroplasts and mitochondria through endocytosis, entrapping the primitive chloroplasts and mitochondria in a second membrane were provided food and energy and in exchange the primitive chloroplasts and mitochondria were offered a safe place to live

Golgi Apparatus

Here proteins are collected and modified from the rough ER and shipped to their final destination again by vesicle transport. only in eukaryotes

Who is Robert hooke

In 1665, Robert Hooke, placed a small sample of cork under a compound light microscope and saw what he described as "small chambers". Hooke settled on calling these chambers "cells" because they reminded him of the rooms or cells in a monastery

spindle fibers

In animal cells, the spindle fibers are produced by the centrioles and help to move and separate the chromosomes during cellular division.

centrioles

Like the cytoskeleton, the centrioles are formed of microtubules. This organelle helps to organize cellular division in animal, but not plant cells.

Chloroplast

a double membrane organelle present in plant cells. is the organelle where photosynthesis occurs and is primarily responsible for converting carbon dioxide, water and solar energy into simple sugars such as glucose

Microfilaments

are composed of proteins called actin and help in cellular movement.

microtubules

are composed of tubulins and are move involved with cell shape. Microtubules also play a key role in cellular division as the mitotic spindle

Mitochondria

are highly complex and important organelles that convert food stored in macromolecules (usually carbohydrates) into usable energy as ATP found in all eukaryotic cells. have two membranes

vesicals

are membrane bound sacs that help to transport large quantities of molecules around the cellVesicles share the same lipid bilayer seen in cellular membranes and can be formed by the budding (pinching off) of the plasma/cellular membrane. found in eukaryotic organisms.

vacuoles

are modified vesicles that store excess nutrients. Plants typically have one large, central vacuole that fills with water which helps to keep plants rigid or turgid, while animals have multiple smaller ones.have a lipid bilayer found in eukaryotic organisms.

Cell Wall

are reinforced structures that surround cells. They exist beyond the cell membrane can are composed of different materials depending on the organism only found in plant cells

lysosomes

are specialized vesicles that contain digestive enzymes. Lysosomes function like a "clean up" crew that digests excess nutrients (carbohydrates, lipids and proteins) and break down old organelles for reuse within the cell found in animal, and sometimes plant

ER

internal membrane system found within eukaryotic cells around the nucleus. This is where lipid and proteins molecules are assembled and packaged.

capsule

is an additional level of cellular protection found in many bacteria cells. The capsule is composed of polysaccharides not found in eukaryotic cells.

cytoskeleton

is literally the backbone of the cell. provides a road network for moving substances throughout the cell. is composed of microfilaments and microtubules and found in all cell types

cytoplasm

is the gel-like matrix that fills the inside of the cell. It exists within the cell membrane, but outside of the nucleus. holds and supports the other organelles with in the cell. All cell types contain cytoplasm

Endocytosis

is used to import large molecules or large quantities of molecules into the cell. The molecules gather on the cell membrane, outside the cell, and the cell membrane begins to bulge inward, eventually pinching off

Smooth ER

lacks the ribosomes, is responsible for building and packaging lipid molecules. Just as in the rough ER, lipid molecules are packaged into vesicles formed from the smooth ER itself. Often the smooth ER contains enzymes to help build these lipid molecules. only in eukaryotes

Rough ER

lined with ribosomes,produce large quantities of proteins. Before the proteins are released from the rough ER, they are packaged into vesicles that bud off the membranous rough ER. only in eukaryotes

Nucleus

protects and houses the DNA in eukaryotic cells.

Ribosomes

ribosomes primary goal is to produce new proteins for the cell. Found freely in the cytoplasm or attached to the endoplasmic reticulum. Found in all cell types.

Cell Membrane

surrounds and protects and cell, separating the cell and its contents from the surrounding environment.is composed of phospholipids, more specifically a phospholipid bilayer and is found in all cell types

Protein channels

that form channels or passages through the cell membrane. Again, these protein channels are very selective, they only allow specific molecules to pass through them do not require energy

Exocytosis

the cell is expelling molecules. A vacuole or vesicle within the cell will fuse with the cell membrane and force its contents out of the cell.

Protein Pumps

transport molecules and ions into and out of the cell This requires energy in the form of ATP from areas of low concentration to high concentration, the reverse of diffusion

Three domains of life.

Domains Bacteria and Archaea are prokaryotic and species under the Eukarya Domain are eukaryotic and include plants, animals and fungi.

3 Things all cells have in common

-All cells have a cell membrane to separate their contents from the environment and help to establish homeostasis. -All cells contain genetic material in the form of DNA. -All cells contain small structures called organelles that each have specific functions and work to support the cell as a whole.

Cell theory

-All living things are made up of cells. -Cells are the most basic unit of structure and function in living things. -All cells come from pre-existing cells

Animal vs plant cells

-Animal cells are typically round and smooth, while plant cells tend to have straighter edges and appear more cubical or boxy due to cell walls. -Animal cells lack cell walls and only have a cell membrane. Plant cells have both a cell wall and cell membrane. The cell wall in plant cells have have varying degrees of thickness depending on the specific plant cell type. -Animal cells lack the chloroplasts found in plant cells, but do have centrioles to aid in cellular division. Plant cell division is slightly different from animal cell division and hence lacks centrioles. -Animal cells have multiple, smaller vacuoles to stores nutrients, while plant cells have one large, central vacuole that is primarily used to store water and provide turgor pressure and maintain the shape of the plant cell. In a plant cell, you can think of the vacuole as a swollen water balloon in a shoe box. The water balloon pushes outward and helps keep the shoebox rigid.

prokaryotic vs eukaryotic cells

-Prokaryotes lack a nucleus, but eukaryotic cells separate their DNA from the rest of the cell in a nucleus. -Eukaryotes tend to have larger cells and a greater diversity of organelles than prokaryotic cells. -Prokaryotic organism tend to be unicellular and their cells are independent, while eukaryotic cells tend to be multicellular and their cells are dependent on one another for survival.

who is Antonie van Leeuwenhoek

Anton van Leeuwenhoek observed pond water under a light microscope and observed what we know today as bacteria. Soon scientists realized that all life was made of cells.