Structures of Eukaryotic Cells

Structures of Eukaryotic Cells

Nucleus: 1.-Brain of cell , the cells control center2.-Surrounded by another membrane/nuclear envelope2.- Contains DNA

-has code for making all proteins/traits of cell4.- Contains pores for items to move in and out.

Nuclear Envelope:-outside of nucleus, studded with pores

Nucleolus:-circular structure within nucleus-makes ribosomes

Nucleoplasm:-cytoplasm inside the nucleus

Chromatin:1.-loosely coiled DNA found within the nucleus

-each human cell has 46 pieces of DNA2.-can tightly coil into a bow tie shaped “chromosome”

Chromosomes are made up of genes.

Genes: -segments of DNA which code for specific proteins

These proteins determine our traits.

Ribosomes:

The cells “workbench”

Job: Makes proteins, in their linear form, by assembling amino acids in the correct order based on DNA’s code.

Ribosomes are made up of RNA and proteins.

Found attached to the endoplasmic reticulum

or

Free floating in the cytoplasm

Endoplasmic Reticulum (ER):-Known as the “cells subway system-Transports proteins around the cell

The E.R is a made up of a series of interconnected, hollow channels.

Two types of E.R:

1. Smooth E.R.-has no ribosomes attached.-responsible for making new membranes for the cell

2.Rough E.R.-has ribosomes attached-helps with protein synthesis

1.Proteins, made by the ribosomes2.Travel through the hollow channels of the rough ER into the smooth ER.

3. The end of the smooth ER pinches off around the protein forming a “transporting vesicle”

4. Transporting vesicle transports the newly formed protein to the golgi body.

Golgi Complex, Apparatus or Bodies

-a stack of flattened membranes clustered in one area.

-Made up of a collection of transporting vesicles.

The golgi is known as the Fed-Ex man

Job: Collects, stores, modifies and packages materials

it receives from the transporting vesicles/ER and then deliver them to where they need to go. This is where a protein gets it 3D shape

Example: Insulin production in a pancreas cell

Mitochondria:

1. -cell’s powerhouse2. -the place were the cell converts food and oxygen into energy.3. -found in all eukaryotic cells~plant-like and animal like.

4. -site of cellular respirationsugar + oxygen ATP energy + carbon dioxide + water

Form of energy used by a cell to do “work”.

-12 to 1000 mitochondria per cell-plant cells have less than animal cells.

Why?-less active-require less energy

-Which cells in our body would have the most mitochondria?

-muscle cells ~ very active

Mitochondria are made up of 2 membranes:-outer membrane-inner membranes known as cristae.

Chloroplast:-Found only in plant-like cells-site of photosynthesis

Sun + CO2 + H2OC6H12O6 + O2

CHLOROPLAST:-Trap energy of the sun and convert

it into sugars which can be stored by the plant or broken down in the mitochondria into ATP energy.

Plant store sugar in their fruits, stems, and roots.

ROY G BIV

Absorbs: -all spectrums of light but green is reflected.

Lysosomes:

Nickname: Clean Up Crew or Suicide Sack

Job: Organelles which contain digestive enzymes made by the ribosomes and processed in the golgi.

Two Jobs:

1. Fuse to an old or damaged cell organelle, injects its enzymes into it and digest the old organelle .

3.Lysosomes in an older or damagedCell breaks open and releases enzymes into theCytoplasm ~ digesting the cell from the inside out.

Example: lifespan

RBC’s 120 daysWBC’s 8 daysSperm 5 days

Lysosomes

LysosomesSee last page of note package:

Formation of a lysosome:

1. Ribosomes make a digestive enzyme2. Enzymes travel through ER3. Smooth ER pinches off and dig. enzyme is contained in a transporting vesicle.4. Transporting vesicle fuses with golgi5. Golgi modifies enzyme giving it a 3D shape6. Section of golgi moves away with enzyme inside it ~ now a lysosome.

Vacuoles: Storage area for cell

Stores excess water, food or

waste.

Plant-like cells have 1 or 2 large central vacuole which stores excess water or sugars

Animals-like cells have many small vacuoles which store excess water and waste.

Plastids: specialized vacuoles in plants

Chloroplast: Stores chlorophyll

Leucoplast: Stores starch

Chromoplast: Stores color pigments

See last page:

Centrioles: used by animal cells to help with cell division

Plant and Animal Cell Comparison

Plant cells have: Animal cells have: cell wall and membrane cell membrane chloroplast no chloroplast 1 or 2 large vacuole many small vacuoles No centrioles 1 pair of centrioles Has plastids No plastids Rectangular in shape Roundish in shape Small # of mitochondria Large # of mitochondria

Prokaryotic and Eukaryotic Cell Comparison

Prokaryotic Cells Eukaryotic Cells

-No nucleus -Has a nucleus-DNA in 1 circular loop -DNA in several linear pieces-Has no membrane bound organelles -Has membrane bound organelles

-both have cytoplasm-both have ribosomes

Ex/ Bacteria Ex/ all protist, fungi, plants and animals