Module 2 Chapter 3 Study Guide

Question 1

Why do cells have to be small in order to function?

Answer 1

Surface area is a factor, surface area is the total area found in the surface of an object. Cells must first cross over this surface area to get nutrients. Being small allows them to do this quickly.

Question 2

Explain how the surface area to volume ratio limits cell size.

Answer 2

If cells were large it would take too long to get the nutrients they need. By staying small they keep a small surface area:volume ratio so materials can quickly diffuse in and out of the cell.

Question 3

State the basic principles of the cell theory

Answer 3

1. All living organisms are composed of cells
2. All cells come from preexisting cells
3. Chemical reactions take place within cells
4. All cells contain hereditary information

Question 4

What is the difference between growth and development.

Answer 4

Growth is physical characteristics like height or weight and development is all the changes from fertilization till death

Question 5

What is metabolism

Answer 5

All chemical reactions that happen in the body

Question 6

What is an organelle

Answer 6

Structure within a cell that has a specific job or function

Question 7

Function of the nucleus

Answer 7

This holds genetic instructions for making proteins that help cellular functions

Question 8

Function of the nucleolus

Answer 8

Produces ribosomes

Question 9

Function of ribosomes

Answer 9

Ribosomes are the site for proteins systems. Makes all the proteins for the cell

Question 10

Function of mitochondrion

Answer 10

The site for cellular respiration. Provides the cell with energy by breaking down glucose to make ATP

Question 11

Function of lysosomes

Answer 11

Vesicles that help break down molecules into smaller pieces.

Question 12

Function of the rough endoplamsic reticulum (RER)

Answer 12

Responsible for making proteins for the cell

Question 13

Function of the smooth endoplasmic reticulum (SER)

Answer 13

Synthesizes lipids

Question 14

Function of the Golgi apparatus

Answer 14

It modifies proteins and lipids. It processes, packages, and secretes. They take into proteins and change them so it can leave the cell in a vesicle

Question 15

Function of centrioles

Answer 15

Organize microtubules that give the cell its shape

Question 16

Function of vesicles

Answer 16

Sacs used for transport, they bring things in and out of the cell.

Question 17

Function of DNA

Answer 17

Contains the specific information needed for the cell to carry out specific functions

Question 18

Function of RNA

Answer 18

Template for all the proteins in the cell, copy for specific instructions

Question 19

Function of nuclear pores

Answer 19

Holes that are in the nuclear envelopes that let substances in and out of the nucleus

Question 20

Can a cell function without all of those organelles ? Explain your answer

Answer 20

All of the function of the cell are linked together so I do not think it could survive with missing even a couple

Question 21

What is necessary for simple diffusion to work?

Answer 21

Requires movement of a substance from a region of higher concentration to a region of lower concentration

Question 22

How is diffusion different from osmosis?

Answer 22

Osmosis moves across a membrane where diffusion moves from an area of higher concentration to an area of lower concentration

Question 23

Upon what is the rate of diffusion dependent (there are a few things)

Answer 23

Surface area, solute, and the gradient

Question 24

How do large molecules get in and out of the cell

Answer 24

Bulk transport, endocytosis and exocytosis

Question 25

What does it mean for a meme brand to be selectively permeable?

Answer 25

It is selective on what it lets into the cell

Question 26

Define osmosis in a cell

Answer 26

The movement of water molecules across a semi permeable membrane.

Question 27

Define the term solvent, solute, and solution

Answer 27

1. Solvent- substances that can dissolve other substances
2. Solute- a dissolved substance
3. Solution- mixture of a solute and a solvent

Question 28

What does tonicity mean

Answer 28

The concentration of solute in solutions on opposite sides of a cell membrane

Question 29

How does the tonicity relate to the direction of water movement across a membrane?

Answer 29

Water will always move in the direction that has more solute. Higher tonicity is higher concentration

Question 30

What is crenation and hemolysis

Answer 30

1. Cremation is when a cell is in hypertonic solution and the water moves out of the cell causing it to shrink.
2. Hemolysis is when the blood cell ruptures from a hypotonic solution

Question 31

Define isotonic, hypotonic, and hypertonic using a red blood cell example

Answer 31

1. Isotonic- concentration of solutes is the same inside and outside of the cell. If the solution is 0.9% salt the solution is isotonic to red blood cells
2. Hypotonic- concentrations of solutes is lower on the outside than on the inside. Any solution less than 0.9% salt the solution is hypotonic
3. Hypertonic- concentration of solutes is higher on the outside than in the inside. Anything over 0.9% salt would be hypertonic to red blood cells

Question 32

Why do human cells need to live in an isotonic environment

Answer 32

So they do not shrink or rupture

Question 33

Why do plant cells need to live in hypotonic environment?

Answer 33

Their cells are more rigid and won’t burst

Question 34

Why does the surface of intestines and the brain have so many folds?

Answer 34

It’s our bodies way of utilizing surface area:volume ration. The small intestine absorbs nutrients from the food we eat. To increase the surface area the small intestines have villi. With the brain it has folds to increase surface area and we are able to make more connections in our neurons

Question 35

Distinguish between the structure of a prokaryotic cell and that of a eukaryotic cell

Answer 35

1. Prokaryotic- lack nucleus, does not contain any membrane bound organelles, smaller in size, unicellular
2. Eukaryotic- has nucleus, has membrane bound organelles, larger, DNA twisted strands

Both have plasma membranes, cytoplasm, DNA, and ribosomes

Question 36

Explain how eukaryotic cell could have evolved from prokaryotic cells

Answer 36

The nucleus could have formed formed by invagination of the plasma membrane come cells bay have arisen by engulfing prokaryotic cells they were not digested but evolved into different organelles (mitochondrion)

Question 37

How does a membrane regulate its size

Answer 37

Endocytosis- removed lipids
Exocytosis- adds lipids

Question 38

Describe the structure of the plasma membrane and list the types of molecules found in the membrane

Answer 38

The plasma membrane is made up of a phospholipid bilayer

Hydrophilic polar heads that faces water and two hydrophobic non polar tails that face inwards towards each other

Intrinsic proteins that serve as channels and extrinsic proteins that serve as communication

Question 39

Why can’t you survive drinking straight seawater?

Answer 39

Become of so much salt the kidneys would receive too much damage and not be able to function properly

Question 40

What would happen to homeostasis if the body no longer produced enzymes?

Answer 40

Necessary chemical reactions would not take place