cell structure and division- biology

Define cell

Basic unit of living organisms

Eukaryotic and prokaryotic ( 1 difference )

eukaryotic has nucleus

Prokaryotic doesn’t

Define microorganism

Organisms you have to use a microscope to see

Things in a prokaryotic cell

Cell wall

Cell membrane

Cytoplasm

Plasmid

Flagellum

Ribosomes

Free floating genetic material

Describe plant cell wall

Made of cellulose

Strong and inelastic

Stops cell from bursting

What is semi permeable in a cell

Cell membrane

Function of mitochondria

Where respiration occurs / releases energy

Function of vacuole

Contains cell Sap

2 types of microscope

Electron and light

What does the fine focus do

Improves resolution

How many objective lenses

3

What does coarse focus do

Moves stage

What does eye piece do

Magnifies

What are the parts of a light microscope

Eye piece

Objective lens

Stage

Coarse focus

Fine Focus

How to make a specimen

Place small piece of tissue on glass slide

1 drop of iodine stain

Cover with cover slip placed at an angle

Total magnification equation

Eye piece x objective lens

size of cell equation

Image size

---

Actual size |. Magnification

Difference between light microscope and electron

Light :

Uses light, lower magnification / resolution , cheaper, uses living specimens, 2D

Electron:

Uses electrons, higher magnification/ resolution, more expensive, uses dead specimens , 3D

Where are the 23 pairs of chromosomes

Nucleus

What are chromosomes made up of

DNA

Define mitosis

A type of cell division which produces two new identical daughter cells diploid

What does mitosis do

Growth repair replacement

Steps of mitosis

(1) parent cell has 23 copies of chromosomes

(2) the chromosomes are duplicated

(3) they pair up in the center of the cell

(4) nucleus divides in two

(5) cytoplasm and cell membrane divide

3 stages of cell cycle

Interphase ( growing)

Mitosis

Cytokinesis ( cell fully splits )

Tissue=

A group of cells workinh together to perform a specific task

Organ=

Group of tissues doing workinh together to perform a specific task

Organ system=

Group of organs workinh together to perform a similar function

How are red blood cells special

Large surface area- biconcave

No nucleus

Small

Sperm is special because

Tail

Lots of mitochondria

Nucleus with half the chromosomes

Head contains digestive enzymes

Root hair cell is special because

Large surface area

Large vacuole

No chloroplast

Thin walls

Define stem cells

Undifferentiated cells that can become any cell in the body

Types of stem cells

Adult stem cells- bone marrow and stuff

umbilical cord stem cells

Embryonic stem cells

Advantages of adult stem cells

No ethical issues

Easy to get

Safe

Disadvantages of adult stem cells

Limited differentiation abilities

Limited diseases it can treat

Patient would need surgery

Painful

Advantages of embryonic stem cells

Can become any cell

Treat lots of disease

Painless

Embryos are available

Disadvantages of embryonic stem cells

Unethical

Side affects

No consent

Harms embryo

Unreliable

What are plant stem cells called and where are they found

Meristems

Tips of root and shoots