CH 4 - Organisms, Cell Structure & Functions

- characteristics of life, organism levels, cellular structure and organelles, cell growth & specialization

6 characteristics of life

1. organization

2. metabolism

3. material exchange

4. responsiveness

5. movement

6. reproduction, growth, development

organization (and example)

organisms’ cells, tissues, organs internal compartments

optimal functioning

ex/ organelles within cells, blood inside vessels, separation btwn extra and intra cellular fluids

metabolism (and example)

energy to fuel

includes catabolic and anabolic systems

catabolism (and example)

process of creating large substances from simple mlcs

ex/ amino acids to proteins

anabolism (and example)

process of breaking down large substances into smaller mlcs, releasing energy

ex/ digestion breaking down food

ex/ maltose breaking into glucose + glucose

____ is the sum of all ___ and ___ reactions within the body

[metabolism] [catabolic] [anabolic]

exchange of material (and example)

organisms interacting with environment

input and output

ex/ ingesting food, expelling waste

ex/ glucose crossing plasma membrane

ex/ ingesting oxygen, expelling co2

responsiveness (and example)

organism’s ability to respond to internal+external changes

ex/ internal: body temp raises → sweat is produced to cool it

external: threat/danger is perceived → brain sends signals to move away

movement (and example)

constantly occurring at all parts within organism

ex/ unicellular: movement of substances in and out of cell membrane

blood moving through vessels, muscle cells contracting,

_____ takes place within all levels of organization

movement

growth, development, and reproduction (and example)

growth - increase in size

• ex/ cell size, number, or non-cellular material increase

development - cell differentiation, growth + repair

reproduction - formation of new organisms from parent organisms

_____ is the specialization of cells

cell differentiation

briefly name (in order) the levels of structural organization

chemical → cellular / organellar → tissue → organ → organ system → organismal level

chemical level (desc and example)

• atoms

• molecules - at least 2 atoms held via chemical bond

• macromolecules - large mlcs formed by

combining small monomer units

ex/ DNA molecule (nucleic acid held via hydrogen bonds)

organisms’ chemical level involves ____, ____, and _____ particles

[atoms] [molecules] [macromolecules]

cellular/organellar level (desc and example)

• organelles - structures within cell membrane providing specialized functions

• cell - fundamental unit of living organisms

• uni or multi cellular

an organism with just a single cell is _____, while an organism with many cells is ______

[unicellular]

[multicellular]

tissue / organ level (desc and examples)

• tissues - groups of similar cells carrying out same function

• organs - tissue sharing common functions that are grouped together, forming organs

list tissues and organs found in the following groups:

• animals

• plants

animals

tissues: muscle , connective , epithelial , nervous

organs: kidney, liver, brain, heart, lungs

plants

tissues: dermal, vascular, ground

organs: root, stem, leaves

organ system / organism levels (desc and example)

high level of organization of functionally related organ groups working to serve specific purpose

ex/ digestive system, respiratory system are organ systems

______ can be unicellular or multicellular

organisms

organisms (desc)

individual living entities (unicellular or multicellular)

list components of the cell structure (10)

• cell membrane

• cytoplasm (internal cytoplasmic compartment)

  • cytosol

  • organelles

• nucleus

  • nucleolus

  • chromatin

  • nuclear pore

  • nucleic fluid

• endoplasmic reticulum

  • smooth ER

  • rough ER

• golgi apparatus

• mitochondria

• vacuole

• vesicles

  • golgi vesicle

  • secretory vesicle

  • transport vesicle

• ribosomes

• lysosome

label the following diagram

_______ separates inner contents of the cell from its external environment

[cell membrane]

_____ and _____ make up the _____, which all multi-cellular organisms contain within their cells

[cytoplasm] [organelles] = [internal cytoplasmic compartment]

internal cytoplasmic compartment

made up of cytoplasm and organelles

organelles

mostly membrane-enclosed bodies performing various functions within a cell

cell membrane: structure + function

structure

• phospholipid bi-layer with proteins, glycolipids, glycoproteins, cholesterol embedded

function

• structure surrounding cell

• A) regulating passage/gateway: separates interior of cell from external environment

• B) regulates material movement in and out of cell

the phospholipid _____ is a ______ barrier; some materials can pass through evenly while others cannot

[bilayer] [selectively permeable]

cytoplasm: structure & function

contents of cell between plasma membrane + nucleus

structure:

• organelles: structures within the cell that have unique operational functions

• cytosol: jelly-like fluid suspending organelles

what % of the cytoplasm is water?

70-80%

endomembrane system (definition + list)

organelle/membrane group that modifies, packages, and transports proteins and lipids

• cell membrane

• endoplasmic reticulum (SER and RER)

• golgi apparatus

• vesicles

• lysosome

endoplasmic reticulum (ER): structure and function

ER - interconnected tubules

Rough ER

structure

• connects to nucleus, studded with ribosomes, flat membranes

function

• makes phospholipids and proteins

• ribosomes on RER synthesize/make the proteins

• chemically modifies those proteins and phospholipids

• transports them to the golgi apparatus in structures called transport vesicles

smooth ER

structure

• connects to rough er, no ribosomes on it, tubular membrane

function

• synthesis of carbs and lipids, detoxes medications and poisons, alcohol metabolism, stores calcium ions

golgi apparatus: structure and function

structure

• stacks of flat membranes

• 2 sides: cis face (facing ER), trans face (facing cell membrane)

function

• transport vesicles fuse onto apparatus (cis face) and empty out contents

• contents (lipids and proteins) from RER undergo further modification

• contents get modified, tagged with mlcs so they are enabled to be routed to proper destination

modified and tagged proteins, lipids exit through the _______ of the golgi apparatus.

they can leave in ____, which deposit them in other parts of the cell, or in _____, which fuse with plasma membrane and release them outside of cell

[trans face], [transport vesicles], [secretory vesicles]

lysosomes: function and structure

structure

• specialized vesicles produced by golgi apparatus

function

• contain digestive enzymes that breakdown organic macromolecules

• recycles organelles

• destroys pathogenic organisms

vesicles: structure and function

structure

• produced by RER, golgi apparatus, cell membrane

• membrane surrounded sacs that carry materials (ex/ proteins, phospholipids)

function

• transport sacs, move materials around the cell

  • can fuse to other membranes (ex/ if coming from RER, it fuses to cisface of golgi apparatus)

ribosomes: structure and function

structure

• 1 small subunit and 1 large subunit join together

• free ribosomes float in the cytoplasm

• ribosomes can be bound to cytoplasmic side of cell membrane or ER

function

• synthesizes proteins

ribosomes are assembled by fusing a large and a small _____ in the _____, then transporting it to the _____ where the final ribosome is assembled

[subunit], [nucleus], [cytoplasm]

in the process of _____, a section of plasma membrane ____ large particles like debris, dead cells to be digested. this section then pinches off from the plasma membrane and becomes a ______. It then fuses with a lysosome, whose ____ ____ destroy the pathogen.

[phagocytosis] [invaginates/engulfs] [vesicle] [digestive enzymes]

mitochondria: structure and function

structure:

• double membrane: inner membrane (cristae folds) + outer membrane

• contains semi-fluid called matrix

• contains its own ribosomes and DNA

function:

• make ATP from glucose breakdown during cellular respiration

nucleus: structure and function

structure

• is continuous with ER

• nuclear envelope: double membrane enclosing nucleus structure

• nuclear pores: passageways in/out of nucleus on the nuclear envelope

• nucleoplasm: semi-fluid inside nucleus holding chromatin, nucleolus

• nucleolus: ribosome factory

• chromatin: DNA chromosomes (linear pieces of proteins) + protein

function

• houses DNA in form of chromatin

• directs synthesis of ribosomes and proteins

____ is part of the cell cycle, which _____

[cell division], [generates 2 new cells]

somatic cell

general term for body cell (except for cells producing sperm/eggs)

germ cells

cells producing eggs and sperm

after cell division, cells _____ and _____

ex/ muscle cell

[grow], [increase in size]

ex/ muscle cells elongate, becoming extremely long as muscle forms

cell differentiation

process of cells achieving final physiology and morphology

cells become specialized to carry out specific funtions

unspecialized cells are ____

[stem cells]

name the following and explain why they take the described shape after cell differentiation:

1. muscle fibers: long and slender

2. _____ / nerve cells: long and thin

3. _____ / red blood cells: tiny, lack of nucleus and mitochondria

4. ____ / white blood cells: larger than _____

1. so fibers can contract and produce movements

2. [neurons]: so they can transmit information

3. [erythrocytes]: no nucleus = squeeze through capillaries. no mitochondria = oxygen they carry doesn’t get used up

4. [leukocytes]: larger than erythrocytes so they can engulf particles/cells