A. Zoology  1. A subset of biology dealing with animals.

 Subsets of zoology – – Entomology – Ichthyology – Ornithology

B. Cells  1. Cells are the basic organizational units of life. 2. Cells can be prokaryotic or eukaryotic.

 3. Prokaryotic cells have no nucleus.  4. Eukaryotic cells have a nucleus containing DNA.

 5. All eukaryoic cells have three basic parts. a. A plasma membrane b. Cytoplasm c. A nucleus

C. Plasma membrane  1. Outer boundary of the cell.  2. Fluid mosaic model – a membrane has two layers of proteins and phospholipids.

 3. The membrane is constantly changing shape and shifting. There may be many types of proteins dispersed through the membrane.

 4. The membrane is selectively permeable. This means they let some things through while keeping others out.

 D. How do things cross the membrane? There are 7 ways!

 1. Simple diffusion – the movement of particles from areas of high concentration to areas of low concentration.

 2. Facilitated diffusion – carrier proteins help molecules get across the membrane.

 3. Osmosis – the diffusion of water. Tonicity refers to the relative concentration of solutes in water inside and outside the cell.

 a. ISOTONIC – same concentration inside as outside the cell. (no effect on cell)

 b. HYPERTONIC – Concentration is higher outside the cell than inside the cell. (The cell shrinks)

 c. HYPOTONIC – Concentration is higher inside the cell than outside. (the cell swells)

 4. Filtration – uses water pressure to force molecules across the membrane.

 5. Active transport – moves molecules from areas of low concentration to high concentration.(opposite of diffusion) Requires ATP energy.

 6. Endocytosis – The bulk movement of particles across the membrane INTO the cell. There are 3 types!

*a. Pinocytosis – the taking in of fluids. *b. Phagocytosis – the taking in of solids.

 *c. Receptor-mediated endocytosis ~ uses a protein to bring molecules into the cell.

 7. Exocytosis – Molecules are removed from the cell in packets called vesicles.

 E. Organelles

 1. VACUOLE – a membrane-bound fluid filled sac within the cytoplasm of a cell. Animal cells have many small ones.

 2. MITOCHONDRIA – among the largest organelles, surrounded by a double membrane, produces small energy packets that can be used by the cell. Powerhouse.

 3. NUCLEUS – large round body, the most prominent structure in the cell, it is enclosed by a nuclear membrane. Chromosomes with genetic info are inside the nucleus.

 4. RIBOSOMES – most numerous and smallest of the organelles, it is the site of protein synthesis. Often associated with endoplasmic reticulum.

 5. ENDOPLASMIC RETICULUM – Makes proteins and hormones.Transports material throughout the cell. Comes in smooth and rough.

 6. GOLGI BODIES – flattened stacked sacs, acts as a distribution center, packages and routes products throughout the cell.

 7. CILIA – Short hair- like projections used for locomotion and to sense the environment

 8. FLAGELLA – long thread-like structures used for locomotion.

 Cilia and flagella have filaments made of a protein called tubulin

 9. MICROFILAMENTS – thin protein fibers in cytoplasm, helps the cell change shape.

 10. MICROTUBULES – hollow cylinders of protein, provide support.

 11. CYTOSKELETON – holds’ the cell upright and helps give it shape, helps it move, and holds other organelles in place.

 12. LYSOSOMES – bags of enzymes, they are involved in breaking down material. “stomach” >

 13. CYTOPLASM – a jelly-like substance made of proteins dissolved in water.

 A semifluid phase of cytoplasm where metabolic reactions occur is called the cytosol.

F. Levels of Organization  1. First level – protoplasmic organization. Examples include euglena, amoeba, paramecium.

 2. Second level – cellular organization, division of labor. Ex. some sponges.

 3. Third level – tissue level, no organs. Ex. Jellyfish

 4. Fourth level – organ level, organs composed of one or more tissues. Ex. flatworms.

 5. Fifth level – system level, organs work together to form systems. Ex. most animals.

G. Tissue Types  A tissue is a group of similar cells specialized for a specific job. There are 4 types of animal tissue.

 1. EPITHELIAL – Usually covers or lines something. – Renewable

– Can be found lining the intestine, in the kidneys, the skin, etc. – Classified on the basis of shape and number of layers present.

– Simple: one layer – Stratified: two or more layers – Squamous: flat – Cuboidal: cube shaped – Columnar: column shaped

 2.CONNECTIVE TISSUE – Supports and binds – Loose connective tissue helps connect skin to underlying muscle.

 Fiberous connective tissue creates very strong cords like ligaments (connect bone to bone) and tendons (connect muscle to bones or other muscles.

 Adipose tissue – fat  Cartilage – hard and flexible tissue for support

 Bone – hard. Provides protection and support. Spaces within bone or cartilage which house the living cells are called lacunae.

 Blood – a fluid connective tissue that transports material throughout the body.

 3. Muscle tissue – Skeletal muscle attaches to bone and is used for movement

– Smooth muscle creates a churning motion and helps move material around inside the body.

– Cardiac muscle is found in the heart.

 Nervous tissue – Neurons are impulse conducting cells

– Neuroglia are involved in protection, support, and nourishment

– Peripheral glial cells form sheaths that protect the nervous system.