A&P Midterm 2

Metabolism

Metabolism

All of the chemical reactions that occur within the body, reactions that build up and break down molecules

Anabolism

Metabolic pathways that construct molecules, requiring energy

Dehydration synthesis

A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule

Catabolism

Metabolic pathways that break down molecules, releasing energy

Hydrolysis

Breaking down complex molecules by the chemical addition of water

Enzymes

Proteins that increase the rate (catalyze) specific metabolic reactions

Active site

A region on an enzyme that binds to a protein or other substance during a reaction

Substrate

A specific reactant acted upon by an enzyme

Metabolic pathway

Series of linked, enzymatically controlled chemical reactions

Rate-limiting enzyme

An enzyme found early in a metabolic pathway that determines the rate of the pathway

Cofactor

A nonprotein, organic molecule or ion that is required for the proper functioning of an enzyme

Denaturation

Loss of normal shape of a protein due to heat or other factors

Excessive heat, radiation, electricity, and pH

Disrupts the rate of reaction of an enzyme and causes it to denature

Oxidation

Loss of electrons

ATP

Main energy source that cells use for most of their work

Glycolysis (anaerobic)

The breakdown of glucose by enzymes, releasing energy and 2 pyruvic acid

Krebs cycle (aerobic respiration)

Pyruvic acid is converted to acetyl Co-A as it enters the mitochondria, citric acid is the first molecule formed, citric acid is broken down and CO2, 2 ATP, NADH, FADH2 are produced

Electron Transport Chain (aerobic respiration)

NADH and FADH pass off their electrons and go through proteins to pump protons which pump through ATP Synthase to convert protons to ATP. Generates 28 ATP

Takes place in the cytoplasm

Glycolysis

Takes place in the mitochondria

Krebs cycle and Electron Transport Chain

2 pyruvate, 2 ATP, 2 NADH

Products of glycolysis

3 NADH, 1 FADH2, 1 GTP/ATP

Products of Krebs Cycle

32-34 ATP, 6H2O

Products of Electron Transport Chain

Gene

A sequence of nucleotide bases of DNA that codes for a protein and thus determines a trait

Pairs with Thymine in DNA

Adenine

Pairs with Adenine in RNA

Uracil

Pairs with Guanine

Cytosine

Genome

Complete set of genetic instructions for an organism

DNA replication

Each new cell copies the original cell's genetic information. Each new DNA molecule consists of one old stand and one new strand

RNA

Transfers genetic information from the nucleus to the cytoplasm

Transcription

The process whereby the DNA sequence in a gene is copied into mRNA

Translation

The process whereby genetic information coded in mRNA directs the formation of a specific protein at a ribosome in the cytoplasm and creates a polypeptide chain

tRNA

Type of RNA that carries amino acids to the ribosome

Anticodon

Group of three bases on a tRNA molecule that are complementary to an mRNA codon

RNA polymerase

enzyme that links together the growing chain of RNA nucleotides during transcription using a DNA strand as a template to create mRNA

Epigenetics

The study of environmental influences on gene expression that occur without a DNA change

Mutation

Change in a DNA sequence that affects genetic information

Substitution mutation

Mutation in which a single base is replaced, potentially altering the gene product

Deletion mutation

Mutation in which one or more pairs of nucleotides are removed from a gene

Insertion mutation

Mutation in which one or more nucleotides are added to a gene

Frameshift mutation

Mutation that shifts the "reading" frame of the genetic message by inserting or deleting a nucleotide

Missense mutation

A nucleotide-pair substitution that results in a codon that codes for a different amino acid

Nonsense mutation

Mutation that changes a normal codon into a stop codon

Duplication mutation

a mutation that involves duplication of a region of DNA on the same strand

rRNA

type of RNA that combines with proteins to form ribosomes

DNA polymerase

Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule

Reversible reaction

A chemical reaction in which the products reform the original reactants

Tight junctions

Close space between cells by fusing cell membranes

Desosomes

Bind cells by forming "spot welds" between cell membranes

Gap junctions

Form tubular channels between cells that allow exchange of substances

Epithelial tissue

Protect, secrete, absorb, excrete, lacks blood cells, cells are tightly packed

Connective tissue

Bind, support, protect, fill spaces, store fats, produce blood cell

Muscle tissue

Generate forces of movement

Nervous tissue

Conduct impulses for coordination, regulation, integration, and sensory reception

Simple squamous epithelium

Single layer, flattened cells, filtration, diffusion, osmosis, covers the surface

Simple cuboidal epithelium

Single layer, cube-shaped cells, secretion and absorption

Simple columnar epithelium

Single layer, elongated cells, secretion and absorption

Pseudostratified columnar epithelium

Single layer, elongated and variously-shaped cells, movement of mucus and substances, absorption, secretion

Stratified squamous epithelium

Many layers, top cells flattened, protection

Stratified cuboidal epithelium

2 or 3 layers, cube-shaped cells, protection

Stratified columnar epithelium

Top layer of elongated cells, lower layers of cube-shaped cells, protection, secretion

Transitional epithelium

Many layers of cube-shaped and elongated cells, stretchability, protection

Merocrine glands

A fluid product released through the cell membrane by exocytosis, sweat glands, salivary glands

Apocrine glands

Cellular product and portions of the free ends of glandular cells pinch off during secretion, mammary glands

Holocrine glands

Disintegrated entire cells filled with secretory products, sebaceous glands

Exocrine glands

Glands that secrete substances outward through a duct

Endocrine glands

Glands of the endocrine system that release hormones into the bloodstream

Areolar connective tissue

Binds organs, fill spaces (beneath skin, surrounds organs)

Adipose tissue

Protects, insulates, stores fat

Reticular connective tissue

Supports, and provides framework of internal organs

Dense regular connective tissue

Withstands great tensile stress with thick collagen fibers when pulling force is applied in one direction tendons, most ligaments

Dense irregular connective tissue

Able to withstand tension exerted in many directions; provides structural strength

Elastic connective tissue

Connective tissue made from elastic fibers that allows stretching (found in the lungs, artery walls, vocal cords)

Cartilage

A rigid connect tissue that provides support, frameworks, attachments, and protects underlying tissues

Hyaline Cartilage

Most common type of cartilage; has very fine collagen fibers, found at end of bones, nose, rings of respiratory passages

Elastic Cartilage

cartilage with abundant elastic fibers; more flexible than hyaline cartilage

Fibrocartilage

A very tough tissue that has many collagen fibers, is a shock absorber for structures

Bone (osseous tissue)

Connective tissue with the matrix hardened by calcium phosphate and other minerals.

Blood connective tissue

Forms red blood cells, white blood cell, and platelets, defends against disease, clotting

Serious membranes

Lines cavities that don't open to outside and reduce friction between organs and cavity walls

Mucous membranes

Lines the cavities and tubes that open to the outside of the body

Skeletal muscle tissue

Voluntary, multi-nucleated, muscle pulls on bones and causes body movements

Smooth muscle tissue

Has no striations, involuntary, spindle-shaped, found in the walls of organs such as stomach

Cardiac muscle tissue

Specialized muscle tissue found only in the heart, involuntary, and striated

Nervous tissue

A tissue that carries electrical messages back and forth between the brain and every other part of the body

Stratum corneum

Outermost layer of the epidermis, which consists of flattened, keratinized cells

Stratum lucidum

Clear, transparent layer of the epidermis under the stratum corneum

Stratum granulosum

Beneath the stratum corneum, three to five layers of flattened granular cells that contain shrunken fibers of keratin and shriveled nuclei

Stratum basale

Deepest epidermal layer made of a single row of cells that undergo rapid cell division, includes melanocytes

Dendritic cells

Within the stratum spinosum to protect skin and deeper tissues from pathogen invasion

Melanocytes

Cells that produce melanin

Cutaneous carcinoma

Most common type of skin cancer, affecting light-skinned people

Cutaneous melanoma

Pigmented with melanin, with a variety of colored areas, variegated brown, black, gray or blue

Eumelanin

Produces brown to black pigments in the hair

Pheomelanin

Produces yellow to red pigments in the hair

Melanin

A pigment that absorbs UV radiation from sunlight, protecting skin cells from damage/mutation

Vasodilation

Widening of blood vessels

Vasoconstriction

Narrowing of blood vessels

Sebaceous glands

Holocrine glands and produce oils to keep hair waterproof

Merocrine sweat glands

Secrete a watery fluid directly onto the surface of the skin to lower body temperature