BIO final exam

Active transport

• ATP Is needed

• move substances against its concentration gradient (low—>high)

• uses protein pumps and carrier proteins

Passive transport

• no atp

• diffusion, osmosis, facilitated diffusion

• substances move with the concentration gradient (high—>low)

What is the cell membrane composed of

• Phospholipid bilayer

  • hydrophobic tails (water fearing)

  • hydrophilic heads (water loving)

Osmosis

water moves across a selective permeable membrane and into areas with high concentration solute

Hypertonic

High solute sconcentration

Why does active transport require more energy than faciltated diffusion or osmosis

Active transport requires more energy because it needs ATP. Osmosis and facilitated diffusion happen with water naturally across the cell. They move from high to low to try to naturally balance out the concentration gradient and reach equilibrium.

Facilitated diffusion

Controls what can travel through the cell.

uses protein pumps (ATP)

Animal cell

• heterotrophs

• no cell wall

• no chloroploast

• flexible

Plant cells

• chloroplast for photosynthesis

• rigid cell walls

What happens to plant cells in hypertonic solution

In hypertonic solutions, the cell becomes turgid (firm) because water comes into the cell. These turgid walls prevent the cell from bursting.

Transmission electron microscope

helped scientists see inside of structures

cell theory

all living things have cells

all cells come from pre-existing cells

Describe the symbiotic relationship between the mitochondria and chloroplast

In this relationship, the mitochondria, cell, and chloroplast all gain something, the chloroplast and mitochondria gain protection, shelter, and food while the cell gainse energy.