structures of eukaryotic cells -nucleus -nucleolus -mitochondria -chloroplast -ribosomes...

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Structures of Eukaryotic Cells-Nucleus-Nucleolus-Mitochondria-Chloroplast-Ribosomes-Endoplasmic Reticulum-Golgi bodies-Lysosomes-Vacuoles-Plastids-Cytoskeleton-Villi

Nucleus: 1.-Brain of cell2.-Cells control center3.-Contains DNA4.-Made up of another lipid bilayer

5.-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 nucleus2.-can tightly coil into a bow tie shaped “chromosome”

Chromosomes are made up of genes.

Genes: -segments of DNA which code for specific proteins

Mitochondria:

1. -cell’s powerhouse2. -the place were the cell converts food 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.

Cristae increase the surface area so more energy can be produced without taking up too much room.

Analogy:

verses

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.

Thylakoids: platelike structures which collect the sun’s energy.

Grana or Granum: Stacks of thylakoids (10 to 100/chloroplast)

Stroma: Liquid part of the chloroplast

Lumen: Inside thylakoids ~ contains chlorophyll

ROY G BIV

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

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 phospholipids for new membranes

2. Rough E.R.-has ribosomes attached-aids in protein synthesis

1.Proteins, made by the ribosomes, travel through the hollow channels of the rough ER into the smooth ER.

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

3. 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.

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. -Where a protein gets it 3D shape

Example: Insulin production in a pancreas cell

Lysosomes:

Nickname: Clean Up Crew or Suicide Sack

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

Three Jobs:

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

2. Lysosomes fuse to food and digest the food for the cell.

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

Example: lifespanRBC’s 120 daysWBC’s 8 daysSperm 5 days

Lysosomes are rarely found in plant cells.-when plant cells die, parts of the cell remains.

Formation of a lysosome:

1. Ribosomes made dig. enzyme2. 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

Cytoskeleton: cell’s framework

Cyto skeleton= cell = support

A woven web-like system embedded into an animal cell’s cell membrane and cytoplasm, provides some support to the cell.

Different animal cells have specific cells:

Cytoskeleton is made up of both:

1. Microfilaments:-long, solid tubes of proteins-allow for movement within cell tissue like muscles.

2. Microtubules:-long, hollow tubes of protein

Flagella: Long whip like tail Cilia: short hairlike

Centrioles: used by animal cells for cell division

Villi: fingerlike projections or extensions of the cell membrane. Increases the surface area of the cell’s membrane.

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

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