Medic14CytologyCh3

• 1. Cells are the building blocks of all plants and animals
• 2. Cells are smallest functional units of life
• 3. Cells are produced by the division ofpre-existing cells
• 4. Each cell maintains homeostasis

Study of cells

The cell membrane. Formed of lipids, proteins and carbohydrates. Proteins in PL-BL serve as receptors, channels, carriers, enzymes, anchors, or identifiers. 

Net movement of material from an area of high concentration to an area of low concentration. Ends when concentration gradient is eliminated. 

Diffusion of water across a membrane in response to differences in concentration. Force of movement of water is called osmotic gradient

Hydrostatic pressure forces water across a membrane. If pores are large enough, molecules of solute will be carried along with the water

A type of carrier-mediated transport that requires the presence of carrier proteins in the membrane

Mechanism that consumes ATP and are independent of concentration gradients. 

Material moves into or out of a cell in membranous sacs. Movement into the cell occurs through endocytosis. Movement out of the cell is called exocytosis.

Membrane enclosed little organs are surrounded by lipid membranes that isolate them from the cytosol. Eg: ER, the nucleus, Golgi apparatus, lysosomes, and mitochondria. Non-membranous organelles are always in contact with the cytosol. They include the cytoskeleton, microvilli, centuries, cilia and flagella, proteasomes, and ribosomes.

Gives cytoplasm strength and flexibility. Main components are microfilaments, intermediate filaments and microtubules. 

Small projections of the cell membrane that increase the surface area exposed to the extracellular environment. 

Direct the movement of chromosomes during cell division

Finger-like projections that beat rhythmically to move fluids or secretions across the cell surface. Ex: found in lungs and small intestine.

Move a cell through surrounding fluid rather and moving fluid past a stationary cell

Is an intracellular factory that manufactures proteins. Free ribosomes are in the cytoplasm, and fixed ribosomes are attached to the endoplasmic reticulum.

Remove and break down damaged or abnormal proteins

Network of intracellular membranes. Rough ER contains ribosomes and is involved in protein syntheses. Smooth ER does not contain ribosomes and is involved in lipid and carbohydrate syntheses.

Forms secretary Vesicles and new membrane components, and it packages lysosomes. Secretions are discharged from the cell by exocytosis.

Vesicles filled with digestive enzymes. Their functions include ridding the cell of bacteria and debris. 

Responsible for 95% of the ATP production within a typical cell. The matrix, or fluid contents of a mitochondrion, lies inside the cristae, or folds of an inner mitochondrial membrane. 

Control center for cellular operations. It is surrounded by a nuclear envelope, through which it communicates with the cytosol by way of nuclear pores. It controls the cell by directing the syntheses of specific proteins using information stored in the DNA of chromosomes. 

A triplicate code of three nitrogenous bases identifying an amino acid. Each gene consists of all the triplets needed to produce a specific protein. 

• Transcription: A strand of messenger RNA is formed and carries protein-making instructions from the nuclear to the cytoplasm
• Translation: A functional protein is constructed from the information contained in an mRNA strand. Each triplet of nitrogenous bases along the nRNA strand is a codon; the sequence of codons determines the sequence of amino acids in the protein.

Brings amino acids to the ribosomes involved in translation

Genetically-controlled death of cells. 

Nuclear division of somatic cells.

Prophase, metaphase, anaphase and telophase. Most cells are in interphase most of the time. 

Division of cytoplasm which creates two daughter cells. 

Abnormal cell growth that is either benign (encapsulated) or malignant (able to invade other tissues). 

The specialization that produces cells with limited capabilities. These specialized cells form organized collections called tissues, each of which has a specific functional role.