study outline exam 1

prokaryotic cells

No nucleus, single circular DNA, 70S ribosomes, reproduce via binary fission.

eukaryotic cells

Have a nucleus, membrane-bound organelles, larger cytoplasm, 80S ribosomes.

mitchondria

Powerhouse of the cell, ATP synthesis

ribosomes

 Protein synthesis (found in cytoplasm and rough ER).

golgi apparatus

Modifies, sorts, and packages proteins.

 Lysosomes

Contains digestive enzymes for breaking down cellular debris

glycolysis

Breakdown of glucose into pyruvate (produces ATP).

citric acid cycle

 Generates high-energy molecules (NADH, FADH2) for ATP production.

Oxidative Phosphorylation

 Electron transport chain produces most of the ATP.

substrate

The molecule upon which an enzyme acts.

product

The result of an enzymatic reaction.

activation energy

The minimum energy required for a reaction to proceed.

epithelial tissue

Covers body surfaces and lines cavities (e.g., skin, digestive lining).

connective tissue

Supports and connects structures (e.g., bone, blood, cartilage).

Muscle Tissue

Facilitates movement (skeletal, cardiac, smooth muscle).

nervous tissue

Conducts electrical impulses (neurons, glial cells).

carbohydrates

Primary energy source; found in grains, fruits, dairy. Carbon chains with hydrogens, oxygens, monosaccharides, disaccharide, and polysaccharides

proteins

Build and repair tissues; found in meat, eggs, legumes. Amino acids, Peptides, Tertiary and Quaternary structures

fats(lipids)

Store energy, form cell membranes; found in oils, nuts, dairy. Triacyle glycerides, phospholipids, cholesterol and sterols. 

vitamins

 Organic compounds required for metabolic functions (e.g., Vitamin C for immunity).

minerals

Inorganic nutrients essential for processes like bone formation (e.g., calcium, iron).

metabolism

is the totality of an organism’s chemical reactions, transforming matter and energy while following the laws of thermodynamics.

catabolic pathways

Break down complex molecules to release energy (e.g., cellular respiration).

anabolic pathways

 Consume energy to build complex molecules (e.g., protein synthesis).

atp hydrolysis

The breakdown of ATP into ADP and inorganic phosphate releases energy.

energy coupling

Exergonic reactions (energy-releasing) drive endergonic reactions (energy-consuming).

substrate

The molecule upon which an enzyme acts

 Product

The molecules formed as a result of the reaction.

catalyst

A substance that speeds up a reaction without being consumed.

activation energy

The minimum energy required for a reaction to proceed.

Denaturation

 Loss of enzyme structure and function due to heat, pH, or chemicals.

enzyme cascades

involve a series of biochemical reactions where one enzyme activates another, amplifying the original signal. This occurs in processes like blood clotting and metabolic regulation.

negative feedback

The final product inhibits the initial enzyme, regulating the pathway.

enzymes

are classified based on the type of reaction they catalyze. Do Note Memorize, note that we name them based on their function and enzymes end in the suffix ase 

Oxidoreductase

Catalyze redox reactions (e.g., dehydrogenases, oxidases).

· Transferases –

·       Transfer functional groups between molecules (e.g., kinases

Glycolysis

the first step in glucose metabolism, converts glucose into pyruvate.

    1. Glucose → Pyruvate

– Occurs in the cytoplasm and generates ATP.

  2.Pyruvate → Acetyl-CoA**

Pyruvate enters the mitochondria for further metabolism.

Krebs cycle

. Acetyl-CoA enters the cycle, producing NADH, FADH2, ATP, and CO2.

oxidative phosphorylation

1. NADH and FADH2 deliver electrons to the electron transport chain.

·       2. Hydrogen ions move through ATP synthase, producing ATP.

Enzymes

are essential for life, facilitating biochemical reactions efficiently. Without enzymes, metabolic processes would occur too slowly to sustain life.

tissues

are groups of cells similar in structure that perform common or related functions. The study of tissues is called Histology. There are four primary tissue types

epithelial tissue

Covers body surfaces and lines body cavities.

connective tissue

Supports, binds, and protects organs.

muscle tissue

Facilitates movement.

nervous tissue

Controls and communicates through electrical signals.

epithelial tissue

forms protective sheets covering body surfaces and cavities. It is classified based on the number of cell layers and cell shape.

polarity

Has an apical (exposed) and basal (attached) surface.

specialized contacts

Cells are closely packed with tight junctions.

Supported by Connective Tissue

Basement membrane anchors it.

avascular but innervated

 Lacks blood vessels but has nerve supply.

regeneration

Cells rapidly replace themselves.

Simple Squamous

 Thin, single-layered cells allowing diffusion (e.g., alveoli, capillaries).

Simple Cuboidal

 Single layer of cube-shaped cells for secretion (e.g., kidney tubules, glands).

simple columnar

 Single tall cells for absorption and secretion (e.g., intestines, uterus).

stratified squamous

Multiple layers for protection (e.g., skin, esophagus).

Pseudostratified Columnar

 Appears layered but all cells touch the basement membrane (e.g., respiratory tract).

Transitional Epithelium –

Stretches in organs like the bladder

Connective tissue

supports, protects, and binds other tissues. It has varying vascularity and is characterized by an extracellular matrix (ECM).

Ground Substance

Fills space between cells (fluid, gel, or solid).

 Fiber

Provide strength and support.

Collagen fibers

Strongest and most abundant.

elastic fibers

Allow stretch and recoil.

   Reticular fibers –

Form delicate networks.

·       Loose Connective Tissue (Areolar, Adipose, Reticular

 Supports organs and stores energy.

Dense Connective Tissue (Regular, Irregular, Elastic)

Provides strength (e.g., tendons, ligaments).

Cartilage (Hyaline, Elastic, Fibrocartilage)

Provides flexibility and cushioning (e.g., joints, nose).

Bone (Osseous Tissue)

Supports and protects organs.

blood

Transports oxygen, nutrients, and waste.

skeletal muscle

Voluntary, striated muscle attached to bones.

cardiac muscle

 Involuntary, striated muscle found in the heart, with intercalated discs.

smooth muscle

 Involuntary, non-striated muscle in hollow organs.

nervous tissue

regulates and controls body functions. It consists of two major cell types:

neurons

Transmit electrical impulses.

glial cells

 Support and protect neurons.

tissue

 repair themselves through regeneration or fibrosis.

Cell Proliferation

Existing cells divide to replace lost tissue.

stem cell activation

 Undifferentiated cells become specialized cells.

 Extracellular Matrix (ECM) Remodeling

Provides structural support for new growth.

age

Younger individuals regenerate tissue more efficiently.

blood supply

 Oxygen and nutrients promote repair.

The integumentary system

 is the body's largest organ system and serves as the first line of defense against environmental factors. It consists of the skin, hair, nails, sweat glands, and sebaceous (oil) glands.

epidermis

The outermost layer providing a protective barrier.

dermis

 Contains blood vessels, nerves, hair follicles, and glands.

Hypodermis (Subcutaneous Layer)

Made of fat and connective tissue for insulation and cushioning.

 Keratinocytes–

Most abundant cell type, producing keratin for protection and water resistance.

  Melanocytes

 Produce melanin, protecting against UV radiation.

Dendritic (Langerhans) Cells

 Immune cells that detect pathogens and activate the immune response.

 Tactile (Merkel) Cells

Touch receptors that detect light touch and texture.

Stratum Basale

 Deepest layer, contains stem cells, melanocytes, and Merkel cells.

Stratum Spinosum

Several layers thick, contains keratinocytes and Langerhans cells.

Stratum Granulosum

 Begins keratinization, forms waterproofing lipids.

Stratum Lucidum (Only in thick skin)

Thin translucent layer for additional protection.

Stratum Corneum

Outer layer of dead keratinized cells, protective barrier.

Protection

Acts as a chemical, physical, and biological barrier.

Thermoregulation

 Regulates body temperature through sweat glands.

sensation

Contains sensory receptors for touch, temperature, and pain.

metabolic functions

Synthesizes vitamin D and detoxifies harmful substances.

melanin

 Provides UV protection; eumelanin (black/brown) and pheomelanin (red/yellow).