A/P intro midterm 2

PMAT

Order of mitosis: Prophase, Metaphase, Anaphase, Telophase.

Interphase

The longest part of the cell cycle. The cell grows and replicates its DNA (G1, S, G2).

G1 / S / G2 phases

G1: cell growth. S: DNA synthesis (replication). G2: final preparation for mitosis.

G0 phase

A resting state in which a cell leaves the cycle and does not divide.

Prophase

Chromatin condenses into chromosomes, the nuclear envelope breaks down, and the spindle forms as centrioles move to opposite poles.

Anaphase

Sister chromatids separate and are pulled to opposite poles of the cell.

Telophase

Chromosomes uncoil, nuclear envelopes re-form, and the spindle disassembles.

Cytokinesis

Division of the cytoplasm. A cleavage furrow pinches the cell into two daughter cells.

Result of mitosis

Two genetically identical diploid daughter cells (46 chromosomes in humans).

Chromatid / Centromere

A chromatid is one copy of a replicated chromosome. The centromere joins the two sister chromatids.

Spindle fibers

Microtubules that attach to chromosomes and move them during mitosis.

DNA replication

Copying DNA before division. It is semiconservative: each new molecule has one old and one new strand.

Transcription

DNA is copied into mRNA in the nucleus.

Translation

mRNA is read at a ribosome to build a protein.

Codon / Anticodon

Codon: three mRNA bases that code for an amino acid. Anticodon: the matching three bases on tRNA.

mRNA / tRNA / rRNA

Carries the genetic message / brings amino acids to the ribosome / forms part of the ribosome.

Nucleolus

Region inside the nucleus where ribosomal RNA is made and ribosomes are assembled.

Chromatin

DNA wrapped around histone proteins. Condenses into chromosomes during division.

Nuclear envelope

Double membrane around the nucleus with pores for transport.

Cytoskeleton

Network of microfilaments, intermediate filaments, and microtubules that supports the cell and moves organelles.

Centrioles

Paired cylinders that organize the spindle during cell division.

Peroxisome

Organelle that detoxifies harmful substances, including hydrogen peroxide, using oxidases and catalase.

Cilia vs. flagellum

Cilia: short, many, move substances along a surface. Flagellum: long, single, propels the cell (sperm).

Microvilli

Finger-like extensions that increase surface area for absorption.

Glycocalyx

Carbohydrate coating on the cell surface used for recognition and protection.

Facilitated diffusion

Passive movement of substances down their gradient through carrier or channel proteins. No ATP.

Filtration

Hydrostatic pressure forces water and small solutes across a membrane (e.g., in the kidneys).

Isotonic solution

Same solute concentration as the cell. No net water movement.

Phagocytosis / Pinocytosis

"Cell eating" of large particles / "cell drinking" of extracellular fluid.

Active vs. passive transport

Active moves substances against their gradient and uses ATP. Passive moves them down their gradient with no ATP.

Atomic number / Mass number

Number of protons / protons plus neutrons.

Isotope

Atoms of the same element with different numbers of neutrons.

Ion / Electrolyte

A charged atom / an ion that conducts electricity in solution (Na⁺, K⁺, Ca²⁺).

Properties of water

Excellent solvent, high heat capacity, cohesive, and a lubricant and cushion.

Acid vs. base

Acid releases H⁺ (pH below 7). Base accepts H⁺ or releases OH⁻ (pH above 7).

Dehydration synthesis

Joining monomers by removing water.

Disaccharide

A double sugar (sucrose, lactose, maltose).

Polysaccharide

A long chain of sugars (starch, glycogen, cellulose).

Triglyceride

Glycerol plus three fatty acids. Main form of stored energy.

Saturated vs. unsaturated fat

Double bonds solid at room tempature

one or more double bonds liquid at room temperature

Steroid

A lipid with four fused carbon rings (cholesterol, sex hormones).

Protein structure levels

Primary: amino acid sequence. Secondary: helix or sheet. Tertiary: 3D fold. Quaternary: multiple chains.

Denaturation

Loss of a protein's shape and function from heat or pH change.

Nucleotide

The monomer of nucleic acids: a sugar, a phosphate, and a nitrogen base.

Simple cuboidal epithelium

One layer of cube-shaped cells for secretion and absorption (kidney tubules, glands).

Simple columnar epithelium

One layer of tall cells for absorption and secretion (digestive tract). Often has goblet cells.

Pseudostratified ciliated columnar

Looks layered but is one layer. Lines the respiratory tract, where cilia move mucus.

Transitional epithelium

Stretchy epithelium lining the urinary bladder.

Exocrine vs. endocrine gland

Exocrine releases products through ducts. Endocrine is ductless and releases hormones into the blood.

Goblet cell

A unicellular exocrine gland that secretes mucus.

Areolar connective tissue

Loose connective tissue that wraps and cushions organs.

Dense regular connective tissue

Parallel collagen fibers forming tendons and ligaments.

Adipose tissue

Stores fat, insulates, and cushions.

Hyaline cartilage

Most common cartilage. Found on bone ends, the nose, and the trachea.

Elastic cartilage

Flexible cartilage of the external ear.

Fibrocartilage

Tough, shock-absorbing cartilage in intervertebral discs and menisci.

Fibroblast

The main cell of connective tissue. Makes fibers and ground substance.

Skeletal muscle tissue

Striated, voluntary, with long multinucleated cells.

Mucous vs. serous membrane

Mucous lines cavities open to the outside and secretes mucus. Serous lines closed cavities and secretes serous fluid.

Cutaneous membrane

The skin.

Regeneration vs. fibrosis

Regeneration replaces damaged tissue with the same type. Fibrosis replaces it with scar tissue.

Epidermal layers

Deep to superficial: basale, spinosum, granulosum, lucidum (thick skin only), corneum. "Come, Let's Get Sun Burned."

Papillary vs. reticular dermis

Papillary: thin, with dermal papillae and fingerprints. Reticular: thick, dense irregular connective tissue.

Hypodermis

Subcutaneous layer of adipose and loose connective tissue beneath the skin. Anchors the skin.

Eccrine vs. apocrine sweat glands

Eccrine: widespread, cools the body. Apocrine: armpit and groin, odor-producing.

Arrector pili

Smooth muscle that pulls the hair upright ("goosebumps").

Functions of the skin

Protection, thermoregulation, sensation, excretion, and vitamin D synthesis.

Skin color pigments

Melanin (brown), carotene (yellow-orange), and hemoglobin (pink-red).

Burn degrees

First: epidermis only. Second: partial thickness with blisters. Third: full thickness, destroying epidermis and dermis.

Rule of nines

Method that estimates the percent of body surface burned.

ABCDE of melanoma

Asymmetry, Border irregularity, Color variation, Diameter over 6 mm, Evolving.

Basal cell carcinoma vs. melanoma

Basal cell is the most common skin cancer. Melanoma is the most dangerous.

Functions of the skeleton

Support, protection, movement, mineral storage, blood cell formation, and fat storage.

Bone shapes

Long, short, flat, irregular, and sesamoid.

Periosteum / Endosteum

Outer fibrous membrane covering a bone / membrane lining the inner surfaces.

Red vs. yellow marrow

Red makes blood cells. Yellow stores fat.

Foramen

A hole in a bone for nerves or vessels.

Fossa / Condyle / Tuberosity

A shallow depression / a rounded articulating projection / a rough projection for muscle attachment.

Intramembranous ossification

Bone forms directly in connective tissue membrane (flat bones of the skull, clavicle).

Endochondral ossification

Bone replaces a hyaline cartilage model (most bones).

PTH vs. calcitonin

PTH raises blood calcium (stimulates osteoclasts). Calcitonin lowers blood calcium.

Wolff's law

Bone remodels in response to the stress placed on it.

Simple vs. compound fracture

Simple (closed): skin intact. Compound (open): bone breaks through the skin.

Fracture healing steps

Hematoma, fibrocartilage callus, bony callus, remodeling.

Osteoporosis

Loss of bone mass that makes bones porous and fracture-prone.

Cranial vs. facial bones

8 cranial bones protect the brain. 14 facial bones.

Skull sutures

Coronal, sagittal, lambdoid, and squamous.

Foramen magnum

Opening in the occipital bone where the spinal cord passes.

Mandible

The only movable skull bone.

Vertebral regions

7 cervical, 12 thoracic, 5 lumbar, then the sacrum and coccyx.

Atlas vs. axis

C1 supports the skull (nodding). C2 has the dens and allows rotation.

True / false / floating ribs

Ribs 1-7 / 8-10 / 11-12.

Parts of the sternum

Manubrium, body, and xiphoid process.

Pectoral girdle

Clavicle and scapula. Attaches the upper limb to the axial skeleton.

Radius vs. ulna

Radius is lateral (thumb side). Ulna is medial.

Hand bones

8 carpals, 5 metacarpals, and 14 phalanges.

Os coxa

Hip bone formed by the ilium, ischium, and pubis fusing at the acetabulum.

Femur

The longest and strongest bone in the body.

Patella

A sesamoid bone in the quadriceps tendon.

Tibia vs. fibula

Tibia is medial and weight-bearing. Fibula is lateral and non-weight-bearing.