LAB 2

metaphase

Metaphase

Chromosomes align in the center at the metaphase plate

-enzyme separate the chromatids from each other

Late prophase

Nuclear envelope breaks down, which allows the mitotic spindle microtubules to attach to kinetochores, a specialized protein at the centromere

 

•Spindle poles are at opposite ends

 

•The kinetochore microtubules pull chromosomes to the center

Late prophase

Anaphase

Centromeres split, and motor proteins in the kinetochores pull the chromosomes toward the pole it faces

 

•Chromosomes take on a “V” shape while moving towards the poles

Anaphase

Telophase & Cytokinesis

Telophase (prophase in reverse)

•Begins when chromosomes stop moving

 

•Chromosomes uncoil forming chromatin

 

•Nuclear envelope and nucleolus reappear

 

•Spindle breaks down

 

•Cell will have a nucleus identical to its parent

 

Cytokinesis (not part of mitosis)

•Division of cytoplasm through contractile ring of actin

Telophase & Cytokinesis

Early Prophase

Nucleolus disappears

 

•Chromatin condenses, forming chromosomes. 2 sister chromatids are held together at the centromere

 

•Centrosomes separate and mitotic spindle forms (microtubules)

Early Prophase

Interphase

Nucleolus and nuclear envelope are visible

 

•DNA is duplicated and is in the form of chromatin

 

•Centrioles replicate.
2 centrioles = centrosome

Interphase

The cell cycle: Interphase + Mitosis

Site of protein synthesis?

Ribosomes

Site of lipid synthesis?

Smooth endoplasmic reticulum

Main site of ATP synthesis?

Mitochondria

Encloses the chromatin?

Nucleus

Packages proteins for transportation?

Golgi apparatus

Sac of digestive enzymes?

Lysosomes

Helps direct mitotic spindle formation?

Centrioles

Intracellular network of rod-like structures?

Cytoskeleton

what attaches to ribosomes ?

Rough endoplasmic reticulum

What detoxifies chemicals in body?

Peroxisomes : sacs containing oxidase enzymes that detoxify alcohol, free radicals, and other harmful chemicals

In general what will happen?

All sacs placed in distilled water will gain mass except for the sac in the beaker with 40% glucose outside (which stays the same)

Water moves into sac because it has a higher solute concentration. Sac gains mass and swells

Sac will stay the same. There is no concentration gradient so no net osmosis

Water moves into sac because there is higher solute there. Sac gains mass.

Sac gains the most mass. Strong gradient so lost of water enters

Phagocytosis (Cell eating)

Pinocytosis (Cell drinking)

Receptor-mediated endocytosis ( molecule specific eating)

Vesicular transport (requires ATP)

Endocytosis

Exocytosis

Endocytosis types

•Phagocytosis (cell eating)

•Pinocytosis (cell drinking)

•Receptor-mediated (molecule specific eating)

Exocytosis

•Secretory vesicles inside the cell move to the plasma membrane, fuse with it & then release its contents outside

•Hormones

•Neurotransmitters

•Mucus

•Ejection of wastes

Simple diffusion

The plasma membrane is a lipid bilayer, which means that only molecules that can dissolve through lipids can pass through the plasma membrane via diffusion

•Examples are O2 and CO2

Facilitated diffusion

If a molecule is not lipid soluble, carrier proteins on the plasma membrane can assist and act as a gate to allow it to pass through and enter the cell

•Example is glucose

Molecules moving down its concentration gradient(high to low)

passive process

Osmosis

movement of water down its concentration gradient

Passive transport

does not use ATP and can be either unassisted (freely moving) via

simple diffusion OR

with help of a protein carrier via facilitated diffusion

Active transport

requires ATP for molecules to move against their concentration gradient

Details of the Plasma Membrane