Cell Bio Chapter 3

Question 1

how many cells in human body

Answer 1

100 trillion

Question 2

3 main parts of cell

Answer 2

nucleus
plasma membrane
cytoplasm

Question 3

why does a cell have a plasma membrane? 3 things

Answer 3

protection

communication

transport

Question 4

what is the plasma membrane made out of?

Answer 4

phospholipids and embedded proteins

Question 5

what is cytoplasm made of?

Answer 5

jelly like substance made of water, salt and proteins

Question 6

what is the cytoplasm’s purpose?

Answer 6

hold the organelles

provides a medium for chemical reactions to occur

Question 7

what is the purpose of the nucleus?

Answer 7

controls growth, reproduction and metabolism

holds the nucleoli, chromosome and chromatin

Question 8

what is the cell membrane made of?
specifically

Answer 8

phospholipids which have hydrophilic heads (face outward) and hydrophobic tails (face inward)

Question 9

what are the 3 functions of the proteins embedded in the membrane

Answer 9

channels

gates

receptors

Question 10

why is the membrane also called the “fluid mosaic”?

Answer 10

because the phospholipids and proteins can move around within the layer

Question 11

what is the outside of the membrane called?

Answer 11

the lipid bilayer (double layer)

Question 12

what is the main structure of the lipid bilayer?

Answer 12

heads that are hydrophilic

tails that are hydrophobic

Question 13

what is cholesterols function within the membrane?

Answer 13

to keep it flexible

Question 14

what is the function of glycolipids in the membrane?

Answer 14

mainly used for receptors and communication (usually facing outwards)

Question 15

what to integral proteins do in the membrane?

Answer 15

they are embedded in the membrane and span across the whole thing, providing transport

Question 16

what do peripheral proteins do in the membrane?

Answer 16

loosely attached to the outside of the membrane, act as receptors and transport substances across the membrane

Question 17

What are ion channels?

Answer 17

specialized doors that open and close to let specific ions pass through

Question 18

what is a carrier? (integral)

Answer 18

specialized carrier proteins that move molecules in and out of the cell (nutrition and waste)

Question 19

What is a receptor? (integral)

Answer 19

essentially an antennae (picking up outside info and relaying it to the inside

Question 20

somatic meaning?

Answer 20

body

Question 21

how many chromosomes do human cells have?

Answer 21

46

Question 22

linker proteins function (integral and peripheral)

Answer 22

connectors that keep structure intact

communication and adhesion between cells

Question 23

enzyme function (integral and peripheral)

Answer 23

assist in various functions on inside and outside of cell (ex chemical reactions)

Question 24

cell identity (glycoprotein)

Answer 24

helps cells communicate and interact with each other

Question 25

What is the liquid bilayer permeable to? (highly permeable to impermeable)

Answer 25

O2, CO2, steroids (highly permeable) water and urea (moderately permeable) ions, large uncharged particles such as glucose (impermeable)

Question 26

concentration gradient meaning

Answer 26

a difference in the concentration of a substance

Question 27

electrical gradient meaning

Answer 27

a difference in the electrical charge across a membrane

Question 28

what are the two types of transport across the membrane

Answer 28

active and passive

Question 29

passive transport meaning

Answer 29

moves substances without the use of energy from the cell

Question 30

active transport meaning

Answer 30

moves substances across the cell membrane with energy (usually ATP)

Question 31

what is simple diffusion?

Answer 31

when a substance moves from an area of high concentration to an area of lower concentration until they are evenly distributed

Question 32

what is facilitated diffusion?

Answer 32

when a substance moves across the membrane with help from special proteins, (but they don't require energy)

Question 33

what is osmosis

Answer 33

when water moves across the membrane from a area of low solute to an area with high solute

Question 34

what is tonicity?

Answer 34

The solute concentration outside the cell is equal to the concentration inside the cell

Question 35

what are the 3 tonicity states? describe the states

Answer 35

isotonic - outside the cell has the same amount of solute as inside the cell hypotonic - outside the cell has less solute than inside the cell (the cell sucks in water and could potentially burst) hypertonic - the outside of the cell has more solute than inside the cell (this causes water to leave the cell and it could shrink)

Question 36

describe vesicle transport

Answer 36

vesicle sacs move the substance from one side of the membrane to the other

Question 37

name the 3 directions of vesicle transport

Answer 37

endocytosis - the substance is moved from outside to the inside of the membrane exocytosis - the substance is moved from inside to the outside of the cell transcytosis - the membrane is moved from one side of the cell to the other (within the cell)

Question 38

what is the cytoskeleton?

Answer 38

a network of protein fibers than form a sort of cage to keep the cells shape (also has roads that allow things to move around)

Question 39

what is one of 3 things that a cell must do?

Answer 39

remain alive and function well grow and divide die

Question 40

What are: DNA expression transcription translation (in simple terms)

Answer 40

DNA template DNA is copied RNA attaches to a ribosome

Question 41

what is mitosis?

Answer 41

the action of duplicating the cells contents and making two identical copies

Question 42

what is meiosis?

Answer 42

reproductive cell division

Question 43

what is cell diversity?

Answer 43

different cells for different purposes

Question 44

What do glycoproteins help with?

Answer 44

cell communication

Question 45

where are phospholipids mainly found in the cell

Answer 45

the lipid bilayer