SCIE- BIO REVIEWER FOR UMAK ENTRANCE EXAM

Carbohydrates

major source of energy and include sugars and starches made up of carbon, hydrogen, and oxygen with a 2:1 ratio of hydrogen to oxygen plants and animals use carbohydrates for maintaining structure within the cells

Proteins

Nitrogen-containing compounds made up of chains of amino acids 20 amino acids can combine to form a great variety of protein molecules can compose enzymes, hormones, antibodies, and structural components

Lipids

water-insoluble (fats and oils) made up of carbon, hydrogen and oxygen; composed of glycerol and fatty acid provide insulation, store energy, cushion internal organs, found in biological membranes saturated (with hydrogen, single bonds, see example ) and unsaturated (double bonds)

Nucleic Acids

direct the instruction of proteins genetic information an organism receives from its parents two types: DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)

Chloroplast

– capture solar energy for photosynthesis (plant cells, some algae)

Golgi Body

– package, distribute products

Lysosomes

– digests excess products and food particles

Mitochondria

– transform energy through respiration

Nucleus

– contains DNA which controls cellular activities

Ribosome

– produce proteins

Vacuole

– store substances

Cell (plasma) membrane

phospholipid bilayer that protects and encloses the cell; controls transport; maintains homeostasis

Cell wall

– rigid second layer that protects and encloses the cell (plant cells and some bacteria)

Cytoplasm

– fluid-like substance that contains various membrane-bound structures (organelles) that perform various functions

Endoplasmic Reticulum

– site of chemical reactions

- ROUGH: contains ribosomes

- SMOOTH: lipid production

Cytoskeleton

– provides internal structure

- MICROFILAMENTS: fibers

- MICROTUBULES: cylinders

Unicellular

– organism that exists as a singular, independent cell

Multicellular

– organism that exists as specialized groups of cells; cells are organized into tissues that perform the same function; tissues form organs and organs make up an organ system

Prokaryote

– has nuclear material in the center of the cell, but is not enclosed by a nuclear membrane; no membrane- bound organelles; found in bacteria and blue-green bacteria

Eukaryote

– contain a clearly defined nucleus enclosed by a nuclear membrane and membrane-bound organelles; found in plants, animals, fungi, and protists

Passive Transport

– movement of substances across the plasma membrane without the use of the cell’s energy (with the concentration gradient)