Unit B homeostasis

What are the 6 functions of the lipid bilayer?

1) Protective barrier around the cell and contains the cytoplasm

2) regulates cell transport in and out of the cell '

3) allows cell recognition, so cells can speak to each other
4) provide anchoring sites for cytoskeleton

5) provide binding sites for enzymes

6) interlocking surfaces that vind cells together.

How does the lipid bilayer control what comes in and out of the cell?

It is like a security fence with gates. The gates are the membrane proteins, and the fence is the phospholids.

What is the structure of the lipid bilayer?

a polar, hydrophilic phosphate head, and 2 nonpolar, hydrophobic fatty acid tails

What will phospholids form when in contact with water?

in water, phospholids form a bilayer, with the water loving heads facing out towards the water and the water hating tails facing the inside of the cell

What is the structure of a phospholid?

a phospholid is amphipathetic (dual natured) —> Hydrophillic and hydrophobic

What are the 3 proteins found on the cell membrane?

• marker protein/glycoprotein —> carb chains that identify cells

• transport/channel proteins —> recieves chemical messages/signals

• receptor proteins —> recieve chemical messages/signals

how does cholesterol help the cell membrane?

cholesterol gives the membrane strength while stilll being fluid/flexible

what is the fluid mosaic model?

a model of understanding of the cell membrane, fluid because the individual phospholids and proteins can move side to side within the layer like it is a liquid, and mosaic because of the patterns this creates when seen from above

what are the 3 ways molecules know which way to go (in/out) of the cell

• Passive transport

• Carrier proteins

• Active transport

What is the concentration gradient of passive transport?

high-low

for which form of transport is energy needed?

actove transport

what are the three kinds of passive transport

• osmosis

• diffusion

• facilitated diffusion

What is osmosis?

how water moves from high-low concentration through the phospholids layer until equilibrium is reached

What is facilitated diffusion?

how large and charged molecules pass through the phospholids layer

What are carrier proteins proteins

proteins that either extend through the membrane or travel through it

how do carrier proteins work?

they bond and drag large molecules through the lipid bilayer and release them on the opposite side

what can cause a carrier proteins to open?

attachment of a hormone

Does active transport require energy

yes

what are the 3 kinds of active transport?

• endocytosis

• exosytosis

• protein pumps

what are protein pumps

a type of protein that uses ATP to carry large molecules through the bilayer, such as sodium and potassium pumps

What is endocytosis

cell takes material in by wrapping its membrane around it, creating a vesicle

what is exocytosis

vesicle fuses with cell membrane and pushes out of the membrane.

What are solutions composed of?

a solute (dissolved) and a solvent (dissolver)

what is the concentration of a given solution

mass/volume

how does water move

from high potential-low potential

what is a hypotonic solution

a solution with a lower concentration of solutes and a greater concentration of solvent

what happens to an animal cell if it fills up with too much water?

it can explode (cytolysis)

What is a hypertonic solution

a solution with a higher concentration of solutes and a lower concentration of solvents

what is an isotonic solution

a solution with equal amounts of solute and solvent

what is dynamic equlibrium

when the water continues moving in and out but at the same amount so there is no net movement.

how do bacteria and plants deal with the pressure of water in cells?

bacteria and plants have cell walls that prevent them from over expanding.

what is the process of not over expanding in plant cells called

tugor pressure

how do protists deal with pressure from water inside the cell?

Protists have contractile valves, which collect water flowing in and pump it out to prevent overexpansion

how do salt water fish deal with pressure from water inside the cell

salt water fish pump salt out of their gills so they don’t dehydrate

how do animal cells deal with water rpessure

animal cells are kept in blood, which is regulated by kidneys for adequate water and salt levels.

What is the purpose of the Exceratry system?

to collect water and filter the water products, then to dispose of concentrated waste

What do Kidneys do for the exceratory system?

filter blood of metabolic wastes, excess water, bicarbonate, sodium, etc

What are kidneys made of

Nephrons

What are nephrons

the microscopic structural and functional unit of the kidney responsible for filtering blood, balancing plasma

How does the kidney help our body?

the kidneys help maintain balance of pH, water, electrolytes, etc

How do the kidneys work?

Blood enters nephrons, gets filtered, and then the helpful substances get reabsorbed back into the blood

How does the kidney regulate water levels in the blood?

Dieuretics and anti-dieuretic hormones

What are dieuretics and what do they do?

Cause less reabsorption of water in the kidneys. Examples include caffeine, and watery fruits/veggies. They are your body produce more urine

What are ADH and what to they do?

A hormone that tells your body to hold onto water, makes urine more concentrated.

How do ADH make you pee less?

it makes walls of collecting ducts more permeable

What is dialysis

artificial filtering of blood

What are the three functions of the exceratory system?

• collect water and filter bodily fluids

• remove and concentrate waste products

• eliminate waste products

what are the two function of the kidneys?

• filer blood of metabolic wastes such as excess water, bicarbonate, salt, and toxins detoxified from liver

• maintain balance of water, pH, electrolytes, etc

what are the kidneys made of?

nephrons, which are tiny functional units of the kidneys

how do the kidneys work?

molecules move from blood to kidneys, and then the fluids are secreted as urine

how does the kidney regulate water levels in blood?

Dieuretic and Anti-Dieruetic hormones

what are the 3 main parts of the heart

Heart, blood vessels, blood

What is the main purpose of the heart?

to pump blood

What is the main purpose of blood vessels?

allowing blood to travel

What is the purpose of blood

fluids being transported

What side of the heart pumps to the lungs?

Right side

Where does the left side of the body pump to

the body

What is the path of blood

vena cava →right atrium →triscupid valve →right ventricle →pulomnary semilunar valve →pulmonary arteries →lungs → pulmonary veins → left atrium → biscupid valve → left ventricle → semilunar valve → aorta

What does the right atrium do?

recieves deoxygenated blood from the body

what does the right ventricle do?

pumps deoxygenated blood to lungs

what does the left atrium do

recieves oxygenated blood

what does the left ventricle do?

pumps blood to body

What are the valves of the heart?

Tricuspid valve, Bicuspid valve, pulmonary semilunar valve, aortic semilunar valve

where is the tricuspid valve?

between right atrium and ventricle

where is the bicuspid valve?

between the left atrium and ventricle

where is the pulmonary semilunar valve?

between the right ventricle and pulmonary artery

where is the aortic semilunar valve?

between the left ventricle and the aorta

why are valves important?

they prevent the backflow of blood intp the atrium and ventricles

when do valves open/close

high/low pressure

What are the major blood vessels?

Superior Vena Cava, Inferior Vena Cava, pulmonary arteries, Pulmonary veins, aorta

what does the superior vena cava do?

brings deoxygenated blood from upper body

what does inferior vena cava do

brings deoxygenated blood from lower body

what do the pulmonary arteries do?

carry deoxygenated blood to lungs

what do the pulmonary veins do?

carry oxygenated blood to left atrium

what does the aorta do?

carries blood from left ventricle to rest of body

What is the systole

systole is the ventricles contracting, and pushing blood out of the heart

what is the diastole

diastole is the ventricles relaxing, and pulling blood in

Where/how does the heart get its own blood supply to function?

The oronary arteries bring oxygenated blood, and coronary veins take deoxygenated blood out

what occurs in 1 full cardiac cycle

1) both atria fill with blood

2) atria contract → blood moves to ventricles

3) ventricles contract → blood moves to body/lungs

4) ventricles relax

What is the pacemaker?

group of cells in the right atrium that generates electrical current to regulate heart rate e

what makes the “lub” sound?

closing of atrioventricular valves

what makes the “dub” sound?

closing of the semilunar valve

when you see “pulmonary” what does that mean

lungs

what are the 3 main blood vessels

arteries, capillaries, veins

what do arteries do?

carry blood away under high pressure

what do capillaries do?

connect veins and arteries, exchange nutrients

what do veins do?

carry blood towards heart

what is blood pressure?

the force of blood against artery walls

how is blood pressure written

systolic/diastolic

what is the pulse?

the expansion of arteries with heart rate

what are the 4 main components of blood?

Plasma, RBC, WBC, platelets

What does the plasma do?

Carries nutrients, hormones, etc

What do red blood cells do?

carry oxygen via hemoglobin

what is the scientific name for red blood cells

erythocytes

what is the scientific name for white blood cells

leukocytes

what do white blood cells do?

defense