structures and life functions of single-celled organisms
TRANSCRIPT
Structures and Life Functions of
Single-Celled Organisms
7.L.1.1 - Compare the structures and life functions of single-celled organisms that carry out all of the
basic functions of life including: • Euglena • Amoeba • Paramecium • Volvox
Let’s Engage Your Brain
Protists and Fungi Kahoot!
Table of Contents Update
Label your table of contents. We will use headings and subheadings in this course.
Heading - 7.L.1.1. - Structures and Life Functions of Single-Celled Organisms
Subheading (indent) - Prokaryotic and Eukaryotic Cells
Vocabulary
eukaryote - a cell or organism that possesses a clearly defined nucleus. The cells of all multicellular organisms (plants, animals, and fungi) are eukaryotic.prokaryote - an organism that lacks a distinct nucleus and other organelles due to the absence of internal membranes. Bacteria and archaea are the best-known prokaryotic organisms. unicellular - organisms composed of a single cell.multicellular - organisms composed of two or more cells.genus - a class, kind, or group marked by common characteristics or by one common characteristiceuglena - any of a genus of green freshwater flagellates often classified as algaeamoeba - are small, one-celled animals that can only be seen under a microscope. They don't have a fixed body shape the way you do.paramecium - a type of single-celled eukaryotic organism. live in water around the world and live mostly by eating other organisms, like bacteria and algae. They're round-shaped, and move around in water using 'broom-like' structures called cilia.
Vocabulary
volvox - any of a genus of single-celled green algae with flagella that form ball-shaped colonies pseudopod - an outward extension of part of a cell that is produced by the pressure of moving cytoplasm (as in an amoeba) and that helps to move the cell and to take in its food.cilia - one of the tiny hairlike structures of many cells that make lashing movements.flagella - a long whiplike structure by which some tiny plants and animals move.autotrophic - organisms that make their own food.protozoans - group of tiny animals (as amoebas and paramecia) that are single-celled protists and have varied structure and physiology and often complicated life cycles.ciliate - any of a group of protozoans that have cilia.algae - any plant or plant-like organism (as a seaweed) that includes forms mostly growing in water, lacking a system of vessels for carrying fluids, and often having chlorophyll masked by brown or red coloring matter.fungus - any of a kingdom of living things (as molds, rusts, mildews, smuts, and mushrooms) that lack chlorophyll, are parasitic or live on dead or decaying organic matter, and were formerly considered plants.
What are prokaryotic and eukaryotic cells?
Learn about them here!
Table of Contents Update
Go to your table of contents. We will continue using subheadings.
Locate the heading - 7.L.1.1. - Structures and Life Functions of Single-Celled Organisms
New subheading (indent) - Protist Characteristics
What do you see?
This photo shows a protist you may be familiar with - seaweed. Write a caption that describes
this protist.http://chrisnelson.ca/photos/var/albums/Two-Harbors-Catalina-
Island/PB010077.jpg?m=1383807713
What are protists?
The kingdom Protista is a group of eukaryotic organisms that cannot be classified as plants, animals, or fungi. They are an extremely diverse group of organisms. Let’s watch a video to learn more.
First, watch the video without taking notes. The second time, pause the video as you watch it to take notes.
Protists Video
What are some characteristics of protists?
Single-celled or multi-celled?
Actually, they can be either. Most are single-celled organisms that cannot be seen without a microscope. Diatoms are one example. They are single-celled with unusually shaped cell walls. Others have many cells, such as brown algae. They can grow several meters long.
See the next slide for images.
Diatom and Brown Algae
https://www.flickr.com/photos/nmnh/3769132239
https://www.lenscope.com/?c=1090
What are some characteristics of protists?
Membrane-Bound
As we learned earlier when discussing eukaryotic and prokaryotic cells, protists have membrane-bound organelles. Organelles assist in performing jobs inside the cell. Certain protists have chloroplasts. Chloroplasts work with energy from the sun to make food for the protist. Not all protists have chloroplasts and are not able to make their own food. We’ll learn more about these jobs in upcoming slides.
What are some characteristics of protists?
Structures for Movement
Some have structures that allow movement. Depending on the protist, the types of structures they have can vary. Protists with these structures can now direct their own movement. There are some protists without these structures, while means they cannot direct their own movement. On the following slides you will learn more about different types of protists, their structures, and basic life functions.
How do protists reproduce?
Asexual Reproduction
Asexual reproduction means offspring is produced by just one parent. Wait! What?
Yes, just one parent. That means every organism can produce offspring on their own. The offspring are genetically identical to its parent and if conditions are favorable, this reproduction can happen quite rapidly.
How does that work?
Well, it can happen in different ways. One way is called binary fission. This is where a single-celled organism copies its DNA, then divides into two cells.
Another way is called fragmentation. This is where a piece breaks off the organism, forming a new individual. Many of the multicellular protists can reproduce this way.
Are there other ways protists can reproduce?
Sexual Reproduction
When protists reproduce sexually, two cells (called gametes), join together. Unlike in asexual reproduction, the offspring have a unique combination of genetic material.
Interesting Fact
Some protists have generations that actually alternate between using asexual or sexual reproduction.
Stop, Jot, and Show Me What You’ve Got!
Think about these three questions and write your response in your INB:
1. How can structures for movement help protists survive?
2. What characteristics do all protists share?
3. What are three ways in which protists can differ from one another?
Table of Contents Update
Go to your table of contents. We will continue using subheadings.
Locate the heading - 7.L.1.1. - Structures and Life Functions of Single-Celled Organisms
New subheading (indent) - Types of Protists
What are the different types of protists?
● Plant-Like Protists● Animal-Like Protists● Fungus-Like Protists
Plant-like Protists
Plant-like protists are producers. This means they use the sun’s energy to make food through photosynthesis. (When something makes its own food, this is called autotrophic) Phytoplankton (single-celled, free-floating, plant-like protists) are a main part of the ocean’s food source for larger organisms.
Multicellular algae are another type of plant-like protist. There are brown algae, green algae, and red algae. The pigment determines the wavelengths of light that can be absorbed by the algae.
Extension of Learning
Watch this video to learn about Algae, Euglena, Volvox, and Spirogyra. Take notes, make sketches, and create diagrams to assist in your learning.
Watch the video here.
Animal-like Protists
Animal-like protists cannot make their own food. They get their nutrients by consuming other organisms such as bacteria, yeast, or other protists.
Most can move around in their environment allowing them to search for food. Sometimes these same structures assist in the consumption of food.
Extension of Learning
Watch this video to learn about Amoeba and Paramecium. Take notes, make sketches, and create diagrams to assist in your learning.
Watch the video here.
Fungus-like Protists
Generally, fungus-like protists do not have the structures needed to move on their own. Since they cannot make their own food and typically can’t move to find food, they absorb nutrients from the environment. This can be off of living or dead organisms.
They produce and release spores (which are also used in reproduction) into the environment. When they land on a good source of nutrition, they stay there and develop into an adult.
Extension of Learning
Watch this video to learn about fungus-like protists. Take notes, make sketches, and create diagrams to assist in your learning.
Watch the video here.
Show What You Know!
Scholars, you are tasked with an activity to “Show What You Know!” You will use your iPad to create a three-column chart. Create headers for each column: Animal-like Protists, Fungus-like Protists, and Plant-like Protists. In each column list three characteristics specific to the type of protist in the column. Finish by finding an image of each protist type, labeled with the name of the organism, and a link to where you obtained your image.
It’s Lab Day
Culture of Diversity
Table of Contents Update
Go to your table of contents. We will continue using subheadings.
Locate the heading - 7.L.1.1. - Structures and Life Functions of Single-Celled Organisms
New subheading (indent) - Protist and Fungi Diversity Lab
Lab Directions
Several microscopes are set up around the room. You will be assigned microscopes to view in a small group.
Section your notebook page into three large sections and two small sections. The top three will be for you to sketch what you see in the microscope. As you look in the microscope, keep your notebook close by.
The last two sections will be used to write and answer the following. Wait to answer these questions until we have completed viewing all of the microscopes and have a class discussion.
1. Of the organisms, which two do you think come from the same kingdom?
2. What does this tell you about the organisms in kingdom Protista?