Cells (Prokaryotic & Eukaryotic)

There are two types of cells Prokaryotes and Eukaryotes

Prokaryotes cells that lack membrane-bound organelles. Bacteria are the only organism to have prokaryotic cells.

Prokaryote Cell

A prokaryotic cell does not have internal organelles surrounded by a membrane. Most of a prokaryote’s metabolism takes place in the cytoplasm.

1. Ribosomes

2. DNA 3. Plasma membrane

4. Cell wall

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Chapter Assessment

Eukaryotes

Eukaryotes have a higher level of complexity.

Eukaryotic Cells contain organelles that are bound by membranes.

All cells other than bacteria are Eukaryotic cells

This eukaryotic cell from an animal has distinct membrane-bound organelles that allow different parts of the cell to perform different functions.

4. Plasma membrane

1. Nucleus

2. Nucleolus

3. Chromosomes

5. Organelles

Chapter Assessment

Components of Cells

Cell Membrane - functions as semi-permeable barrier. Allowing a few molecules across it while fencing the majority of organically produced chemicals inside the cell.

Cell Walls

The Cell Wall is a structure surrounding the cell membrane.

Cell Walls contains cellulose that makes the cells more ridged.

Plants and Plant-liked organisms have cell

walls

The Plasma Membrane

Cytoplasm

The cytoplasm is defined as the material between the cell membrane and the nucleus of a cell.

A semi-gel fluid that helps moves substances in a cell.

Organelles

Organelles are formed bodies within the cytoplasm that perform certain functions in a cell.

Examples include: nucleus, ribosomes, endoplasmic reticulum, mitochondria.

Nucleus /Nucleolus/Nuclear membrane or envelope

The nucleus controls the functions of the cells

The nucleus is found only in eukaryotic cells.

The nucleolus found in the nucleus is where nucleotides are constructed, begins the assembly of ribosomes.

Nuclear membrane (con’t)

The nuclear membrane or sometimes called the nuclear envelope is a double-membrane structure.. Numerous pores occur in the envelope, allowing RNA and other chemicals to pass, but not DNA.

Chromosomes

Chromosomes are found in the nucleus. They may appear as “Xs”.

Chromosomes contain the hereditary material of DNA which control all cell activities.

Chromosomes are able to replicate or reproduce.

Centrioles

Play a major role in cell reproduction only found in animal cells.

Generally only seen during cell division

May look like a long cylindrical asterisk in most models

Cytoskeleton

The cytoskeleton is a network of protein filaments that helps the cell to maintain its shape. The cytoskeleton is also involved in movement.

Vacuoles

Vacuoles are usually a storage area and recycling site.

Vacuoles usually appear larger in plant cells than in animal cell.

Plant Cell

Animal Cell

Ribosomes

Ribosomes are the sites of protein synthesis

Some ribosomes are free floating some are attach to endoplasmic reticulum.

Endoplasmic Reticulum Rough and Smooth Endoplasmic

Reticulum Rough ER Serves the function of

storing and transporting proteins. Rough ER is so named because of its

rough appearance due to the numerous ribosomes that occur along the ER.

Smooth ER contains collections of enzymes that perform tasks such as synthesizing membrane lipids and the detoxifications of drugs. Named because it does not have ribosomes attached to it

Mitochondria

Mitochondria function as the sites of energy production.

The mitochondria has been termed the “powerhouse” of the cell.

Golgi Apparatus

Golgi bodies are flattened stacks of membrane-bound sacs (looks likes pancakes).

They function as a packaging plant, for carbohydrates and proteins.

Lysosomes

Lysosomes are the “disposal units” of cells

Lysosomes function in the extracellular breakdown of materials.

Generally found only in animal cells.

Plastids (Chloroplast, Leucoplast, & Chromoplasts) Chloroplast - are the

sites of photosynthesis in eukaryotes.

They contain chlorophyll , the green pigment necessary for photosynthesis

Leucoplast

Leucoplast- stores starch.

Leucoplast are most likely found in the roots tissue of most plant. Example: potato

Chromoplast

Stores pigments associated with the bright colors of flowers and or fruits.

Cilia & Flagella

Cilia and Flagella are similar except for length, cilia being much shorter (hair-like). Flagella are long whip-like.

Both are responsible for movement.

Cilia on a paramecium

Flagella on a Euglena