Bio Exam 1 - Animal structures

Question 1

Plasma membrane

Answer 1

Surrounds the cell as a phospholipid bilayer that is embedded with proteins and creates a semi-permeable membrane. cholesterol provides support and carbohydrates provide recognition

Question 2

characteristics of plasma membrane

Answer 2

• can change lipid composition based on temp
• more thick and sticky at moderate temps which protect against solidification - done through cholesterol
• unsaturated hydrocarbon tails prevent packing - remains fluid
• saturated hydrocarbon tails pack together increasing solidity

Question 3

integral - membrane protein

Answer 3

penetrate the hydrophobic interior of bilayer

Question 4

peripheral - membrane protein

Answer 4

are not embedded but loosley bound to surface of membrane

Question 5

what are the six major functions of membrane proteins?

Answer 5

transport
enzymatic activity
signal transduction
cell-cell recognition
intracellular joining
attachment

Question 6

What does it mean to be selectively permeable?

Answer 6

• membrane allows for some things to enter and some cannot enter - based on size and charge
• small non charged molecules can freely cross
• are driven by concentration gradient

Question 7

concentration gradient

Answer 7

• to go down a gradient is to go from a high concentration to low concentration which does not require use of energy
• to go up means going from lower to higher gradient and requires the input of ATP energy

Question 8

transport

Answer 8

• passive - diffusion and osmosis - get across with zero help
• facilitated - aquaporins - water goes through a channel to get in - Na and K ions channels
• active - requires use of ATP - the Na/K pump
  vesicular - endocytosis and exocytosis

Question 9

endocytosis

Answer 9

process of capturing a substance from outside the cell by engulfing it and bringing it toward the inside of cell - vesicle that pinches off and transports around inside of the cell

Question 10

exocytosis

Answer 10

process by which vesicles fusing with the plasma membrane and releasing their contents to the outside of the cell

Question 11

diffusion

Answer 11

random movement of molecules from a higher concentration to a lower concentration - O2 and CO2 enter/exit this way

Question 12

osmosis

Answer 12

diffusion of water down the concentration gradient

Question 13

isotonic

Answer 13

solutions have equal parts solute inside and outside of the cell and has no effect

Question 14

hypotonic

Answer 14

solutions have less solute than inside of cell and lead to lysis or bursting - water diffuses into cell

Question 15

hypertonic

Answer 15

solutions have more solute than inside of cell and lead to crenation - shriveling - water diffuses out of cell

Question 16

facilitated transport

Answer 16

transport of molecules across the plasma membrane from higher to lower concentration via a channel protein or carrier protein - no ATP needed - passage of amino acids or glucose and water

Question 17

carrier protein

Answer 17

alternates between two shapes moving a solute across the membrane during shape change

Question 18

active transport

Answer 18

Movement of molecules from lower to higher concentration and needs ATP - requires protein carrier
molecules or ions bind with carrier proteins called pumps and move against gradient

Question 19

bulk transport - under active

Answer 19

endocytosis - engulfing - transport without proteins
phagocytosis - large matter such as food molecules, viruses, or whole cells
pinocytosis - liquids and small particles dissolved in liquid
receptor mediated endo - type of pino that involves a coated pit - placental cells

Question 20

bulk transport example

Answer 20

human cells use receptor mediated endo to take in cholestorol for membrane synthesis and synthesis of other steroids

Question 21

rate of exchange

Answer 21

proportional to a cell’s surface area

Question 22

amount of material exchanges

Answer 22

proportional to a cell’s volume

Question 23

interstitial fluid

Answer 23

space between cells that allows for the movement of material into and out of cells

Question 24

intracellular fluid

Answer 24

fluid inside the cell

Question 25

four main types of tissue

Answer 25

epithelial muscle nervous connective

Question 26

epithelial tissue

Answer 26

- covers internal and external surfaces - cells are connected by a basement membrane - shapes are squamus, cuboidal, columnar - # of layers are simple for one, stratified for multiple, pseudostratified - one but have multiple nuclei per cell

Question 27

connective tissue

Answer 27

- contained within the extracellular matrix and attaches tissue - loose tissue - binds epithelia to underlying tissue - adipose fat - fibrous - found in tendons and attaches muscle to bone and ligaments connecting bone to bone - fluid - blood composed of cells and cell fragments - supporting - bone and cartilage - mineralized material

Question 28

muscle tissue

Answer 28

long cells called muscle fibers, which contract in response to nerve impulses - skeletal - does voluntary movement - cardiac - does contractions of the heart - smooth - does involuntary movement

Question 29

nervous tissue

Answer 29

senses stimuli and transmits signals throughout the animal neurons - nerve cells that transmit nerve impulses glia - help to nourish, insulate, and replenish neurons transmits info between specific locations impulses are received by neurons, muscle cells, endocrine cells, and exocrine cells

Question 30

nervous system

Answer 30

transmits electrical signals via chemicals called neurotransmitters to receptive cells in body via synapses has short lived effects and is fast acting

Question 31

endocrine system

Answer 31

transmits chemical signals called hormones to receptive cells through body via bloodstream can affect one or more region in body slow acting but have long lasting effects

Question 32

homeostasis

Answer 32

internal balance regardless of the external environment

Question 33

For a given variable...

Answer 33

a set point determines the steady state and fluctuations above or below serve as a stimulus that are detected by a sensor that triggers a response

Question 34

control center

Answer 34

integrator

Question 35

response

Answer 35

effector

Question 36

hypothalamus

Answer 36

regulates body temperature

Question 37

regulator

Answer 37

controls internal change in the face of external fluctuation

Question 38

conformer

Answer 38

allows its internal conditions to vary with certain external changes and matches their internal to external

Question 39

endotherms

Answer 39

derive heat from metabolism and are regulators

Question 40

ectotherms

Answer 40

body temp is derived from environment and are conformers

Question 41

behavioral thermoregulation

Answer 41

mechanism that causes ectotherms to search out cold or hot environments to regulate their internal environment