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study of patterns and processes by which an individual survives and reproduces in the environment

cells need these two elements/molecules to survive

carbon dioxide and oxygen

A method that animal and plant cells use to achieve homeostasis


surface-to-volume ratio

volume increases in three dimensions. area increases in two directions

is diffusion easier in thin or thick areas?


where do big animals gather substances for internal use?

the outside environment

Two ways substances can be transported (internally)

active transport and by following concentration gradients

these two types of transport help maintain the internal environment and metabolism by adjusting the kinds, amounts, and directional movement of substances

active and passive


place where individuals of a species normally live

what makes up a habitat?

soil, air, animals, water, and plants in the area

interstitial fluid

fills the places between cells and tissues


fluid portion of blood

what does interstitial fluid exchange substances with?

cells and blood

sensory receptors

cells or cell parts that detect stimuli (forms of energy). They then send signals to the brain.

Negative feedback mechanism

homeostatic control mechanism that reduces the output of the stimulus. fixes changes in the internal environment


central command post that receives and processes information about stimuli


carry out suitable responses to the stimulation

whats and example of a receptor triggering changes?

slowing down of the entire body and its cells to counteract overheating

positive feedback mechanisms

initiate a chain of events that intensify change from an original condition and after a limited time, the intesification reverses the change. Usually associated with instability in a system

Organ systems of nearly all animal are controlled by what?

neural and endocrine control


community of cells and intercellular substances that are interacting in one or more tasks


structural unit of at least two tissues, organized in certain proportions and patterns, that carries out one or more common tasks

organ system

A group of two or more organs that interact to perform a set of related tasks


increase in the number, size, and volume of cells. Measured quantitatively


series of stages in which specialized tissues, organs, and organ systems form. measured qualitatively

internal environment

made up of extracellular fluid. Changes in its composition and volume affect cell activities

what do all animals and plants require for all of their living cells?

a stable fluid environment

most common type of feedback mechanism



first layer of cells to form in the embryo of nearly all animals


Tissues that cover the internal and external surfaces of the body, the cells of which are held together with specialized structures such as tight junctions. Arise from the ectoderm


sheetlike tissue of cells that are close together, with little extracellular material between them. Absorb or secrete

stratified epithelium

epithelium that has cells that form two or more layers

where do gland cells occur?

in epithelia

what maintains solute-water balance in humans?



concentration and removal of substances that are of no use to the body


when a functionally specialized substance (especially one that is not a waste) is released from a gland or cell


saclike, secretory organs that open to the free epithelial

exocrine glands

have ducts or tubes that open onto the free epithelial surface. secrete many substances, such as oils, mucus, saliva, tears, milk, digestive enzymes, and earwax

endocrine glands

have no ducts. they secrete their products, hormones, directly into interstitial fluid

adhering junction

adjoining cells are welded together with a mass of proteins, which is anchored under the plasma membrane by tufts of intermediate filaments of the cytoskeleton

tight junction

strands of proteins running parallel with the free surface of the tissue. they block leaking between adjoining cells. Stop most substances from leaking across a tissue

gap junction

cylindrical arrays of proteins span the plasma membrane of adjoining cells. they pair up as open channels for signals between cells. Permit ions and small molecules to pass freely from the cytoplasm of one cell to another.

Which of the following is the correct order of levels of structural organization?

cell, tissue, organ, organism

A series of stages in the formation of specialized tissues and organs is called _____.


Which of the following plant structures functions most like the human reproductive system?


The structural and physiological characteristics of all plants and animals are specifically adapted to their _____.


The internal environment consists specifically of fluids in _____.

interstitial fluid and plasma

In a typical feedback loop, an integrator involves the _____ system and an effector involves the _____ system.

nervous, glandular

Panting, sweating, and dilation of surface blood vessels in response to overheating are examples of _____.

negative feedback

Positive and negative feedback help maintain the internal environment in a state of _____.


In plants, the physical isolation of an injured or infected site is called _____.


In cellular communication, a receptor site is activated by _____.

binding to a specific signal molecule

Cellular communication involves sending signals, receiving signals, and _____

inducing change in a target cell's activity

A community of cells that interacts together to perform a specific task is called a/an _____.


Which of the following plant structures would be most comparable to the human vascular system?

xylem and phloem


vascular tissue responsible for the transport of nutrients and the carbohydrates produced by photosynthesis

Which mechanism allows a substance to move against its concentration gradient?

active transport

Surface-to-volume ratio is most critical to which metabolic process?

rapid gas exchange

Interstitial fluid is found _____.

between cells

In a feedback loop, which of the following is the correct pathway from stimulus to response?

receptor, integrator, effector

The process of homeostasis that tends to cancel or counteract the effects of the original stimulus is called _____.

negative feedback mechanism

The protective mechanism in which plants release signal molecules that diffuse to undamaged tissues is called _____.

system-acquired resistance

he leaves of the yellow bush lupine conserve water by _____.

trapping moisture lost from stomata in folded leaves


the small openings on the undersides of most leaves through which oxygen and carbon dioxide can move

For cells to communicate, a _____ must reversibly bind to a _____.

signal molecule, receptor protein

Programmed cell death is controlled by _____.


Epithelium often overlies connective tissue; a(an) _____ forms the attachment between the two tissues.

basement membrane

Exocrine glands differ from endocrine glands in that they _____.

have ducts which carry products to a free epithelial surface

How do the products of endocrine glands reach the appropriate target cells?

products diffuse into the blood and are transported by the circulatory system

To better coordinate its activity, the heart is formed from cells that are connected to one another with _____ junctions.


Using anatomical terminology, it would be correct to say that the elbow is _____ to the shoulder.


A beauty-salon permanent begins by applying a chemical to the hair that _____.

breaks the disulfide bonds between adjacent keratin chains

In which tissues could abundant collagen and elastin be found?

connective tissues

Which answer correctly matches a muscle characteristic with the appropriate muscle type?

branched cells, cardiac muscle

Which nerve cells relay commands from the brain or spinal cord to muscle cells?

motor neurons

Hair is primarily composed of _____.

keratin fibers

A penetrating injury to the lungs would require entry into the _____ cavity.


ndividuals with a relatively thick layer of _____ tissue may experience less discomfort as the temperature falls.


The activity of _____ results in a tan after adequate exposure to the sun.


Which of the following forms a thick protective barrier that can keep bacteria from entering the body?

stratified squamous epithelium

Tendons connect bone to _____, while ligaments connect bone to _____.

muscle, bone


cushions and protects the joints between bones

Which muscle type is classified as voluntary?


sensory neurons

detect specific stimuli, such as light, heat, and pressure

An epithelium made up primarily of flattened cells is called _____.


Which of the following tissue types can currently be grown in the lab to replace damaged tissue in humans?


Mucus, saliva, earwax, milk, and digestive enzymes are considered exocrine products because _____.

each is produced within an exocrine gland and transported by a duct to a free surface

Vas deferens

a duct that carries spermatozoa from the epididymis to the ejaculatory duct

Urogenital sinus

point where the vagina joins with the urethra

Hard palate

the bony part of the roof of the mouth


the part of the small intestine between the stomach and the jejunum


throat; passageway for food to the esophagus and air to the larynx

Lymph nodes

filters or traps for foreign particles and contain white blood cells


the two upper chambers of the heart- the receiving areas that pool incoming blood.


organ that removes urea, excess water, and other waste products from the blood and passes them to the ureter


relating to or situated in or extending toward the middle


toward the outside of the body


close to a point of reference


farther from a point of reference

connective tissue

Have connecting roles in the body. Structurally or functoinally support, bind, seperate, and in one case, insulate other tissues

What is the main type of cell in every tissue in the body except connective tissue?



Make and secrete structural fiber of collagen and elastin

Loose connective tissue

fibroblasts and fiber are dispersed widely throughout the matrix. Most common in the vertebrae body. Help organs and epithelia stay in place

Fibrous, Irregular Connective Tissue

Matrix is packed with many fibroblasts and collagen fibers that are positioned every which way. Is a component of skin that supports intestinal muscles and also forms protective capsules around organs that do not stretch much

Fibrous, Regular Connective Tissue

Has orderly rows of fibroblasts between parallel, tightly packed, bundles of fibers. Helps keep tissue from being torn apart whrn placed under mechanical stress. Tendons and ligaments are examples

In ligaments, what thing, found in the tissue matrix, facilitates movements around joints?

elastic fibers


a connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together

bone tissue

hardened connective tissue that is the main tissue of bones. Some bones are sites of blood cell formation

Adipose Tissue

Energy reservoir where excess carbohydrates and lipids are converted to fats. The fats then form an insulating layer and cushion certain body parts and organs such as kidneys and hearts


considered a connective tissue because its cellular components arise from stem cells in bone, a connective tissue

where are blood cells suspended?


what does plasma consist of?

proteins, gases, ions, sugars, and other substances that are dissolved in it

red blood cells

get oxygen to metabolically active tissues and get rid of carbon dioxide wastes

white blood cells

patrol, defend, and repair tissues


Function in blood clotting

How many types of tissue do vertebrates have?


Muscle Tissues

Consist of many cells arranged parallel to one another, in tight or loose arrays. Coordinated contractions of layers or rings of muscles move the whole body or its component parts

skeletal muscle tissue

functional partner of bone and cartilage. Helps move and maintain the positions of the body and its parts. Consists of groups of cells fused together

cardiac muscle tissue

occurs only in the heart wall. Contains sarcomeres. Consists of single, branching cells that have a nucleus. At their ends, adhering junctions help keep them from being ripped apart during forceful contractions.


the basic contractile unit of striated muscle; the segment of a myofibril between two adjacent z-lines.

smooth muscle tissue

has single, unbranching cells, tapered at both ends. Contracts slower, but longer than skeletal muscle. Found in the stomach, bladder, and uterus

nervous tissue

composed of neurons and a variety of cells, collectively called neuroglia, that structurally and functionally support them


Excitable cells that make up the communication line in most nervous systems


Signaling molecules that diffuse to another cell

what do sensory neurons detect?

specific stimuli (light, pressure, etc.)


receive and integrate sensory information. sore the bits that hold meaning and coordinate the body's short term and long term responses to stimuli

motor neurons

relay commands from the brain and spinal cord to muscle cells, and to glands


The outer layer of primary tissue. Gives rise to epidermis and the nervous system


The middle layer of primary tissue. Start of muscles, bones, and most of the circulatory, urinary, and reproductive systems


Inner primary tissue layer. Start of the lining of the digestive tract and organs derived from it

Integumentary system

Protects the body from injury, dehydration, and some pathogens. Controls temperature and excretes wastes

Nervous system

Detects external and internal stimuli. Controls and coordinates the responses to stimuli; integrates all organ system activities

Muscular System

Moves the body and its internal parts; maintains posture and generates heat

Lymphatic System

Collects and returns some tissue fluid to the bloodstream; defends the body against infection and tissue damage

Skeletal System

Supports and protects body parts; provides muscle attachment sites; produces red blood cells; stores calcium and phosphorous

Respiratory System

Rapidly delivers oxygen to the tissue fluid that bathes all living cells; removes carbon dioxide wastes of celss

Circulatory System

Rapidly transports many materials to and from cells; helps stabilize internal pH and temperature

Endocrine System

Hormonally controls body functioning, works with the nervous system to integrate short-term and long term activities

Digestive System

Ingests food and water; mechanically and chemically breaks down food and absorbs small molecules into the internal environment; eliminates food residues

Urinary System

Maintains the volume and composition of the internal environment; excretes excess fluid and blood-borne wastes

Reproductive System

Females produce eggs and males produce sperm that fertilize the egg. Hormones of this system also influence other organ systems


at or near the back of the body


of or near the head end or toward the front plane of the body

frontal plane

divides the body into anterior and posterior

transverse plane

splits the top and bottom of a body

dorsal surface

Along (or toward) the vertebral surface of the body

ventral surface

surface near or on the belly

pelvic cavity

Contains the urinary bladder, the reproductive organs, and the last part of the large intestine.

cranial cavity

in the skull, encases the brain

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