Cell Structure and Function Eukaryotic Cell Structure Plant Cells vs. Animal Cells

Here are two types of eukaryotes Plant Cell Animal Cell

What is the cell membrane? Thin double-layered sheet surrounding the cell Flexible structure that forms a strong barrier between the cell and its environment Regulates what enters or leaves the cell Semipermeable Provides protection and support

What is the nucleus? Controls most cell processes. Contains the hereditary information of the cell (DNA) Surrounded by a double membrane (nuclear envelope) Provides support Controls movement of substance into and out of the nucleus.

What is the nucleolus? Small, dense region inside the nucleus Produces rRNA which later joins with proteins to form the subunits of ribosomes

What is the cytoplasm or cytosol? Fluid made of mostly of water, salts, some proteins, and many organelles Found outside the nucleus and inside the cell membrane Site of many of the cell’s chemical reactions

What are ribosomes? Small particles of rRNA and proteins Found throughout the cytoplasm or attached to the endoplasmic reticulum. Ribosomes assemble proteins. Cells active in protein synthesis are often packed with ribosomes.

What is the endoplasmic reticulum? Internal membrane system that processes and transports proteins within the cell The rough ER is in the synthesis of proteins. The smooth ER makes lipids. It’s also involved in some cellular processes such as regulating and releasing calcium ions, and processing toxins. In the testes and adrenal cortex, smooth ER produces steroid hormones, in the liver is involved in the detoxification of drugs.

What is the Golgi apparatus? Stack of folded membranes Modifies, sorts, and packages proteins and other materials from the ER for storage in the cell or secretion outside the cell.

What are mitochondria? The powerhouse of the cell! Aerobic RESPIRATION happens here. They use oxygen to breakdown food molecules (glucose) and release the energy that has been stored in chemical bonds to recharge lots of ATP! In humans, all or nearly all of our mitochondria originate from the cytoplasm of our mother’s ovum.

What are vacuoles? Saclike structures Store materials such as water, salts, proteins, and carbohydrates Plant cells have a single, large central vacuole filled with liquid that provides internal pressure/support.

What is the cytoskeleton? Network of protein filaments Helps the cell to maintain its shape. Involved in movement. Microfilamentsand microtubules are the two of the principal protein filaments

lysosomes Small organelles filled with enzymes. Waste is expelled by exocytosis Useful stuff is recycled and used by cell Small organelles filled with enzymes. Formed by the Golgi apparatus. Digest macromolecules such as lipids, carbohydrates, and proteins into small molecules. Break down organelles that have outlived their usefulness. Food Vacuole Fingers of a human embryo are at first webbed, but they are freed from one another by lysosomal action. Lysosome Food or bacteria are taken in by endocytosis Damaged Mitochondria in a vacuole

What are chloroplasts? Capture the energy from sunlight and convert it into chemical energy (sugars) in a process called photosynthesis Chloroplasts contain the green pigment chlorophyll

What is the cell wall? Extra layer that surrounds the cell membrane. Gives additional support, shape and strength to the cell. In plants, the cell wall is made of cellulose.

Flagellum and Cilia They are made of microtubules Used for movement of the cell (or of the environment it’s found in). Usually one flagellum Usually many cilia

How are plant and animal cells similar? Have cell membranes that enclose the cell Have cells filled with cytoplasm Have a nucleus Have ribosomes Have mitochondria Have vacuoles Have endoplasmic reticulum Have Golgi apparatus Have a cytoskeleton (microfilaments and microtubules)

How are plant and animal cells different? Plant Cell Animal Cell Rectangular shape Have cell walls. Have chloroplasts for photosynthesis. Have only one large central vacuole No lysosomes Circular shape No cell walls No chloroplasts/no photosynthesis Have many small vacuoles Have lysosomes