bio exam 3

the smallest unit of organization is

cell

group of cells that share similar structure and function is a

tissue

group of tissues that perform specialized functions is called a

organ

group of organs that work together to accomplish one or a few related functions is called a

organ system

connective tissue characteristics include

-cells interspersed throughout a extra cellular matrix

-provides structure, support, anchors cells, and regulates communication between cells

epithelial tissue characteristics include

-cells that cover and line most surfaces of animal bodies

-forms the skin and the lining of the lungs, digestive, and blood vessels

muscle tissue characteristics include

-cells that can contract

-generates movement, pumps fluid, and moves substances

nerve tissue characteristics include

-specialized cells that send and receive electrical signals

-stores and transmits information

which tissue acts as a barrier between the inside and outside of an organism and keeps fluids from leaking into and out of the tissue

epithelial

which tissue regulates movement of nutrients and other molecules into and out of body tissues (gas exchange)

epithelial

which tissue can form exocrine glands, which secretes saliva, sweat, and mucus, and endocrine glands that secrete hormones

epithelial

osteoblast means

bone

chondrocyte means

cartilage

ECM means

extra cellular matrix

what are fibroblasts?

cells that produce and secrete the proteins collagen and elastin (present in every type of tissue except blood)

whats a matrix?

a non living, extracellular mass of protein fibers and surrounding liquid, jelly like, or solid material (collagen, elastin, and surrounding)

what provides support and attachments also cushions bones

cartilage/ chondrocytes

loose connective tissue is

semi fluid, flexible matrix, cushions, lubricates, and insulates other tissues (ex. soft padding under the skin, tissue surrounding most organs)

dense connective tissue is

matrix is tightly packed with many collagen fibers, connects bones to muscles and other bones (ex. tendons and ligaments)

special connective tissue is

connective tissue that has a liquid or rigid extracellular matrix

bone includes a matrix that is

hardened with calcium into a solid material

and provides protection and structural support

cartilage includes a matrix that is

strong but flexible that is rich in protein fibers

provides structural support and cushioning in joints

blood includes a matrix that is

liquid (plasma) that consists of primarily water

transports gases and substances throughout the body

fat does not have a lot of

extra cellular matrix

skeletal muscle

generates most of the movement in animals

both conscious and unconscious control

have multi nuclei

cardiac muscle

muscle in the heart that pumps blood through the body

under unconscious control

smooth muscle

generates slow rhythmic contractions that can gradually move food or substances through the body or alter blood pressure

under unconscious control and can generate contractions without nervous stimulation

Two types of nervous tissue are

neurons and glial cells

cells that can receive and transmit signals are called

neurons or nerve cells

what receives signals from the external environment

dendrites

contains the nucleus and other cellular machinery

cell body

a single projection from the cell body that transmits impulses away from the cell body

axon

glial cells do what

they assist by insulating, protecting, and regulating their chemical environment, holding them in place, destroying pathogens, and providing nutrients and oxygen

each organ is made of several tissues that cooperate to perform specific functions true or false

true

when a xenotransplant occurs what might the surgeons have to do, in order for the organ to work within a human body?

alter the genes

incubate the organ with solutions and drugs to make it suitable

when they want to engineer certain tissues, whats the process?

get the stem cells from the tissue, isolate them so they expand in culture, add it to a scaffold into a bioreactor then implant

the cells used to regenerate the windpipe were taken from the patients bone marrow and then

grown on a shaped scaffold (for the organ, ex. trachea) for days before transplantation into the patient

whats internal regulation called

homeostasis

homeostasis is

the maintenance of relatively constant internal environment

what happens if homeostasis fails

exertional heatstroke could be deadly

ECF means

interstial fluid

thermoregulation is maintaining what

temp

osmoregulation is maintaining what

water

negative feedback is a good true or false

true positive feedback is bad

stimulus —> brain—>

target tissue—>response

In negative feedback loops, sensors detect ___ in the internal environment and triggers ______ to oppose or reduce the change

changes; effectors

ex. of negative feedback mechanisms include

thermoregulation and osmoregulation

in the positive feedback system, such as blood clotting, a ____ away from conditions causes an _____ or acceleration of the change

change; increase

positive feedback is generally part of a larger negative feedback system bc after a while the variable is brought back with8in its typical ranges true or false

true

endotherms are

warm blooded (generate heat internally) ex. mammals, birds

ectotherms are

cold blooded (get their heat from their environment) ex. fish, snakes

whats the only mammal that is not endothermic

naked mole rat

what helps in heat loss?

increasing blood flow to surface blood vessels

elephants dont sweat?

no, the cracks in their skin holds moisture tho

dingo’s pant (physiological)

squirrel shield itself from the heat of the sun (behavioral)

walrus thick coat of blubber for insulation of its environment (physical)

infant have a type of fat that produces heat (cellular)

all of these aid in temp regulation

3 reasons why we need food

-energy

-raw materials to build organic compounds

-essential nutrients (fatty acids, amino acids, vitamins, and minerals)

digestion consists of two processes

mechanical (chewing and tearing)

chemical (enzymes)

digestive process is four phases

ingestion, digestion, absorption, and elimination

what are the three helping organs

liver, gallbladder, and pancreas

in a molecule of protein, what is the enzymes involved and where does this occur

pepsin, trypsin, chymotrypsin; stomach and small intestine

in a molecule of starch, what is the enzyme involved and where does it occur

amylase; mouth and small intestine

in a molecule of sugar, what is the enzyme involved and where does it occur

disaccharidases; small intestine

in a molecule of fat, what is the enzyme involved and where does it occur

lipase; small intestine

physical digestion starts in the

mouth with teeth

chemical digestion in the mouth is from

salivary glands that release saliva

saliva contains

mucus, lysozymes, buffers, amylase, and water

whats a lysozyme

defensive enzyme (breaks up bacteria)

whats amylase

a digestive enzyme (breaks down carbohydrates)

breaks starch into maltose (a disaccharide)

chewed food + saliva =

bolus

whats the epiglottis

it closes over the windpipe as bolus passes through the esophagus (swallowing)

the esophagus uses what type of waves instead of digestion

peristaltic waves (wave like contractions that move food toward the digestive tract)

3 roles of the stomach

sanitizes, mixes, stores

chemical digestion of proteins starts where

stomach

gastric glands produce 3 things

mucus, HCI (hydrochloride acid), pepsin

the only digestive enzyme active in the stomach

pepsin

what requires low pH for strong activity

pepsin

what enzyme chemically digests proteins into polypeptide chains

pepsin

bolus+gastric juices=

acid chyme which leaves the stomach and enters the small intestine

too much of H. pylori can cause

ulcer problems

too little of H. pylori can cause

obesity

H. pylori positives include

regulates stomach acid, controls obesity by regulating the stomach hormone, ghrelin

gastroparesis means

stomach paralysis

what are the three macromolecules

carbohydrates, fats, and proteins

proteins is broken down into polypeptides called

amino acids

the liver produces

bile

the bile is stored in the ______ and then enters the __________ by way of the ________

gall bladder; small intestine; bile duct

what is the active component in bile

bile salts

emulsifies means

the bile salts break lipids into smaller pieces

pancreatic juices contain

buffers (HCO3-) neutralized solution and enzymes including trypsin, chymotrypsin, amylase, and lipase

acid chyme is neutralized by the

buffers in the pancreatic juice

all pancreatic enzymes act in the

small intestine

pancreatic amylase digests

starch into maltose

chymotrypsin digests

polypeptides into dipeptides

trypsin digests

polypeptides into dipeptides

lipase glycerol digests

lipids into fatty acids

all of the pancreatic enzymes are produced in the _____ but they work in the ______

pancreas; small intestine

does bile chemically digest lipids

no, they mechanically do

endocrine cells make

insulin to balance your blood sugar on the bottom half of the pancreas

our small intestine is

20 ft in length

all of the absorption of food molecules happens in the

small intestine