Whole Body Functioning

Question 1

distinguishing factors of passive transport

Answer 1

no energy required

always down a gradient

Question 2

down what sort of gradients does passive transport occur?

Answer 2

concentration gradient (nutrients)
electrical gradient (ions)
pressure gradient (gases)
electrochemical gradient (combined electro and concentration gradients)

Question 3

types of passive transport

Answer 3

diffusion/osmosis

facilitated diffusion

Question 4

what is diffusion/osmosis and what substances use it?

Answer 4

hydrophobic molecules, small uncharged polar molecules
directly across the membrane
occurs whenever there is a gradient
very fast over short distances

Question 5

what is facilitated diffusion and what substances use it?

Answer 5

large uncharged polar molecules, ions

through a membrane channel or transporter (water through an aquaporin)

Question 6

what does active transport require to work?

Answer 6

ATP (energy)

Question 7

2 types of active transport

Answer 7

primary active transport

secondary active transport

Question 8

what is primary active transport?

Answer 8

ATP used directly for the process
transports substances against their electrochemical gradient
creates electrochemical gradients

Question 9

what is secondary active transport?

Answer 9

uses electrochemical gradients created by primary active transport
the movement of one substance down its gradient drives the movement of another substance against its gradient

Question 10

what is bulk transport (flow)?

Answer 10

fast over long distances
all solutes and water move together in the same direction
requires pressure gradients

Question 11

bulk transport in cells

Answer 11

occurs in organ systems to transport substances to and from cells
cell transport occurs through the cell membrane to transfer substances into cells, and wastes out of cells

Question 12

how do bulk transport, diffusion & bulk flow work together in the digestive system?

Answer 12

bulk transport:
food bolus moves through stomach & intestines
diffusion:
nutrients & water diffuse -> from gut tube in epithelial cells -> into the blood
bulk flow:
blood flows through blood vessels

Question 13

how do bulk flow & diffusion work together in the respiratory system?

Answer 13

bulk flow:
air flows through airways to lungs
diffusion:
oxygen diffuses form lungs into blood
carbon dioxide diffuses from blood into lungs
bulk flow:
blood flows through blood vessels

Question 14

how do bulk flow & diffusion work together in blood?

Answer 14

bulk flow:
blood flows through the heart & blood vessels (cardiovascular system)
diffusion:
oxygen, nutrients, & water diffuse out of the blood, into cells
carbon dioxide & wastes diffuse out of cells, into blood
bulk flow:
blood flows through blood vessels

Question 15

how do bulk flow & diffusion work together in the urinary system?

Answer 15

bulk flow:
blood flows through a ‘filter’ into the kidney tubules, creating pre-urine
diffusion:
nutrients, ions, wastes, toxins, and water diffuse across tubule cells, or flow to become urine
bulk flow:
blood flows through blood vessels
urine flows down into bladder, then out urethra

Question 16

what is homeostasis (balance)?

Answer 16

a balanced internal environment

many variables need to be kept within a set range to ensure cells can function

Question 17

homeostasis maintains what variables?

Answer 17

blood glucose (fuel for cells)
blood pH (acidity affects protein functioning)
blood osmolarity (needs to stay the same as inside cells so water doesn't move in/out of cells)
blood pressure (ensure blood gets to all cells)
blood temperature (affects protein functioning)

Question 18

function and purpose of blood glucose

Answer 18

primary fuel to make ATP
cells also use other blood fuels (fatty acids, amino acids)
fuel from body storage (glycogen or fat) or from food & drink

Question 19

function & purpose of blood fuel

Answer 19

muscle cells need fuel to make ATP
so muscles can contract and make the legs move
harder they work, more food they need

Question 20

purpose & function of blood pH

Answer 20

measure of acidity
refers to the concentration of hydrogen ions in blood
food we eat & breathing rate affect acidity
muscle cells produce waste as they work
co2 & h+ wastes increase blood acidity
breathing increases to rid more co2

Question 21

purpose & function of blood osmolarity

Answer 21

the ratio of solutes to water
plasma osmolarity must = ICF osmolarity or water moves in/out cells (affecting functionality)
food & fluid, environment & activity levels affect plasma osmolarity
increased blood osmolarity occurs when dehydrated
decreased blood osmolarity occurs when over-hydrated

Question 22

purpose & function of blood pressure

Answer 22

mean arterial blood pressure (MABP) is the average blood pressure within all arteries
needs to be high enough to control flow
blood volume, heart rate & blood vessel width affect BP
extreme exercise & hydration state increases MABP

Question 23

purpose & function of blood temp

Answer 23

optimum blood temp is 37˚C
hotter temp = protein damage
colder temp = processes slow/stop
food & fluid, hydration state, activity level & environment affect core temp
heat is produced when working muscle cells create & use ATP
heat loss through sweat, vasodilation, breathing
heat gain through shivering, vasoconstriction

Question 24

2 types of control to maintain homeostasis

Answer 24

feedforward (preparation before)
negative feedback (correction after)

Question 25

example of feedforward

Answer 25

“I am going to watch his body language so I can anticipate when to jump”

Question 26

example of negative feedback

Answer 26

“I jumped too late. need to jump earlier to get it”

Question 27

components of negative feedback

Answer 27

stimulus
sensor
control centre
effector

Question 28

stimulus function

Answer 28

something disturbs balance

variable goes out of range

Question 29

sensor function

Answer 29

cells detect the change

Question 30

control centre function

Answer 30

cells signal to effectors to correct the change

Question 31

effector function

Answer 31

effector cells do something that will correct the change and restore homeostasis