Processes of Life and Cell Theory/ Origins

By Tafesse

Metabolism

Living things have chemical reactions that take place in their cells.

Respond to Stimuli

Living things respond to changes in their environment

Homeostasis

Living things maintain constant internal conditions despite external changes in their environment

Movement

Living things have some control over their place and position in the environment.

Growth

cells can increase in size over a period of time. in multicellular organisms growth can also refer to a increase in the number of cells.

Reproduce

Living things all produce offspring’s. Can be sexual or asexual.

Excretion

Living things must facilitate the removal of their own metabolic waste products.

Nutrition

Living things must obtain energy and nutrients from the environment.

Blood is not the main food source for mosquitoes. they feed on nectar and sap from plants. but females need the protein in blood to make eggs.

Nutrition

Carnivorous plants photosynthesize but have evolved to digest prey to supplement the nitrogen they get from the nutrient poor soil.

Nutrition

Fish excrete ammonia directly into water through there gills.

Excretion

Humans produce urea which is a major component of urine

Excretion

Adult salmon swim back from the ocean they live in to streams for the females to hatch their eggs and for the eggs to be fertilized by the males.

Reproduce

Queen bee’s Mate with male bees/drone’s to lay eggs in the honeycomb which then hatch to become worker bees.

Reproduce

Penguin chicks grow rapidly developing from fluffy, down covered babies to sleek water proof adults.

Growth

Coral polyps grow by dividing and forming colonies, which expand and harden overtime to create extensive coral reefs.

Growth

Sunflowers slowly turn their flowers to continuously face the sun

Movement

Ants form organized trails as they march towards a food source guided by pheromone signals and led by fellow colony members.

Movement

The pancreas releases insulin to lower glucose levels and glucagon levels

Homeostasis

salamanders can regulate their body temperature by moving between sunny and shaded areas and adjusting their activity levels accordingly.

Homeostasis

Plants stems grow towards light (Phototropism) and their roots grow down due to gravity (Gravitropism)

Respond to stimuli

Some fungi release spores based on changes to humidity and light.

Respond to stimuli

Humans break down glucose and oxygen to produce energy.

Metabolism

Fish convert ingested plants into amino acids.

Metabolism

4 structures a cell has

Cell membrane

Cytoplasm

DNA

Ribosomes

Tenant of cell theory 1

All living organisms are composed of one or more cells.

Tenant of cell theory 2

cells are the basic units of life and must be able to carry out all processes of life.

Tenant of cell theory 3

Cells come from pre-existing cells

Implication 1 of Cell Theory (Unicellular)

Unicellular organisms must be able to complete all 8 processes of life withing their single cell.

Implication 2 of Cell Theory (Virus)

Viruses are not cells. They are not living.

What did Redi’s Experiment conclude

Redi’s Experiment Prematurely proved Spontaneous generation Is not possible because maggots only appeared in the open jar.

What was pasture’s Experiment

Boiled water in a swan neck flask to see if unaffected water would house spontaneously created bacteria

What did Pasture’s experiment conclude

Spontaneous generation Is not possible

What are the three tenants of cell theory

1. All living things are made of one or more cells

2. Cells are the basic units of life

3. All cells come from pre-existing cells

What were the conditions of Early earth

Lack of oxygen and Ozone

Abundance of Carbon Dioxide

Uv light was able to hit the surface of earth

What did miller-Urey Attempt to recreate and investigate

The conditions of Early earth And investigate Types of molecules that could form.

Define Prebiotic

Existing or occurring before the emergence of life.

What gasses did Miller-Urey use?

H20, Methane, Ammonia, Dihydrogen, Heat, and Electricity.

What did Miller and Urey create

Amino acids/Organic Molecules

Define Organic

Molecules that contain carbon

What is a criticism of the Miller-Urey experiment

We don’t actually know if these were the original conditions on earth.

How and where were Protocells formed

1. Aqueous environment

2. Self replication and self assembly

What is a Protocell

The original cells formed

How does a cell membrane form?

Fatty Acids will assemble into spherical bilayers

What does a cell membrane do?

It seperates the internal environment of the cell from the external environment

Which process of life is the cell membrane directly associated with.

Homeostasis

Why is RNA thought to have been the first genetic material

RNA connects to Ribosomes which are one of the building blocks of a cell

What is some evidence of LUCA

1. Universal genetic code

2. Conserved genes across all organisms

What is LUCA

Last Universal Common Ancestor

When did LUCA Exist

2.5 - 3.5 Billion years ago

Characteristics of LUCA

• Unicellular

• Autotropic Microbe

Where is it believed LUCA was formed

Hydrothermal Vents