Draw a cell 1. fold a page in half 2. on the top half draw a circle 3. on the bottom half draw a rectangle 4. each represents a cell type label one ‘animal and one ‘plant’

nucleusendoplasmic reticulumchloroplast centriole golgi apparatuscell wall vacuole mitochondria now add the following (without looking at your notes) read the list and plan ahead before starting not all parts will be in both cells

nucleus round endoplasmic reticulum membrane touching nucleus golgi complex floating membrane mitochondria sausage shaped – interior structure Animal cell

nucleus endoplasmic reticulum vacuole large, empty golgi complex cell wall thick, outside membrane chloroplast oval with green insides mitochondria

Cell Specialization and Tissues sexually reproducing organisms start out life as a fertilized egg cell  a zygote mitosis allows this one cell to divide into many billions of cells

without cell specialization you would just be a big ball of identical cells all doing identical things

cell specialization occurs when any one cell differs from those around it in appearance or function

Factors That Influence Cell Specialization 1. the cell’s cytoplasm the cell organelles may NOT be equally distributed after mitosis a cell may get more: vacuoles  storage golgi  packaging mitochondria  energy ribosomes  proteins

temperature cells are exposed to may influence expression of genes all cells in the Siamese cat have the potential to make the black pigment, but only the cells below 36 o C do so 2. environmental conditions

nutrients available to the cell how much and what a stem cell is ‘fed’ affects its development

3. the effect of neighbouring cells where a cell is in a multicellular organism influences how it behaves

each cell receives chemical signals from the cells around it a cell receives different signals based on where it is in the organism these signals then cause the cell to differentiate appropriately

it is why we have a thumb and four fingers, rather than just all fingers and no thumb

Types of Animal Tissues 1. Epithelial these tissue form a layer around other tissues a. skin epithelia flat cells that form a semi-permeable barrier between the body and the outside world

b. columnar epithelial cells lining the intestine, stomach, glands secrete mucous,absorb materials

2. muscle a. skeletal muscle made up of long cells that align to look striped attach to bonesto allow movement can contract quicklyand with force

b. smooth muscle made up of cells that do not look striated (striped) found in blood vessels, contract slowlybut can sustain contractions digestive organs

c. cardiac muscle appear to be striated unevenly work together, all contract at once do NOT get tired found only in the heart

3. nervous consist of neuron cells which have long projections to receive & transfer signals function to coordinate body actions

4. connective a. bone consists of proteinhardened by calcium needed for protectionsupport& movement

b. fat or adipose tissue large cellsaround organs and under skin provide energy storageand insulation whale blubber

c. blood red blood cells carry oxygen to cells

white blood cells attack invaders to protect the body

platelets release fibrin to clot the blood

Types of Plant Tissues 1. Meristematic Tissue unspecialized tissue capable not dividing of dividing by mitosis not dividing dividing only found in root tips, buds and cambium

2. Epidermal Tissue protective outer coating

involved in water entering roots

and gases entering or leaving leaf

3. Ground Tissue provides support for stem all 3 are ground tissue

storage of food and water in roots

site of photosynthesis in leaves all the cells with chloroplasts

4. Vascular tissue xylem moves water & dissolved minerals up from the roots series of tubes moving water & minerals up

phloem moves dissolved sugars (food) down from the leaves series of tubes moving water & sugars down

xylem & phloem are found together in a vascular bundle cambium is meristematic tissue that makes xylem & phloem

Comparing animal and plant tissues: Explain why each animal tissue corresponds to the given plant tissue

epithelialepidermal both protect connectiveground tissue both support both store vascular tissue muscle animalplantwhat they have in common both transport (remember arteries & veins are muscles tissue) meristematic tissuenone all animal tissue can divide & grow both allow entry animals absorb, plants allow entry

Challenges with cell specialization a. regeneration if a salamander loses a limb it can regenerate

but humans can not  why

before birth all stem cells are set in humans

b. manipulating stem cells unspecialized stem cells can be taken from an unwanted embryo

problems of moral issues

more recently differentiated adult cells have been turned into unspecialized stem cells

value of stem cells 1. replace cells damaged by drugs / radiation eg. bone marrow in cancer treatments

2. replace nerve cells as these do not grow in adults eg. spinal injuries

3. replace diseased cells eg. leukemia

4. replace worn out organs eg. grow a bladder in the lab from own cells