Exam 2: Lecture 10 ( Chapter 28)

Question 1

Protists

Answer 1

Informal term to describe any eukaryotes that arent plants, animals, or fungi

Question 2

What separates Eukaryotes from Prokaryotes

Answer 2

• Nucleus
• Membrane-enclosed organelles
• Well-developed cytoskeleton

Question 3

Protists evolved through ________, which gave birth to the ________.

Answer 3

Endosymbiosis, Mitochondria

Question 4

_______ arose after mitochondria when a _________ eukaryote engulfed a _________ bacterium

Answer 4

Plastids, heterotrophic, photosynthetic

Question 5

Define the Excavata group and name some examples

Answer 5

Characterized by their cytoskeleton morphology, include protists with modified mitochondria and flagella
- Diplomonad
- Parabasalids
- Euglenids

Question 6

Define some characteristics of Diplomonad

Answer 6

Have mitosomes (reduced mitochondria, generates energy anaerobically), mostly parasites, and have two equal sized nuclei with multiple flagella

Question 7

Define some characteristics of Parabasalids

Answer 7

Have hydrogenosomes (reduced mitochondria, generates energy anaerobically)
- Release hydrogen as a byproduct

Question 8

Define some characteristics of Euglenids

Answer 8

• have 1 or 2 flagella emerging from the end of the cell
• have Pellicles, a stiff structure that keeps their shape

Question 9

What are Stramenopiles

Answer 9

Most important phototrophs on earth
- have hairy and smooth flagella
- Include Diatoms, brown algae, and oomycetes

Question 10

What are Diatoms

Answer 10

Unicellular algae with a unique glasslike wall of silicone dioxide.

• Diatoms are abundant and their photosynthetic activity influences global CO2 levels
• Important carbon pump

Question 11

What are brown algae

Answer 11

They are the largest and most complex multicellular algae
- often called seaweeds, form forests, and share many analogous traits with plants

Question 12

What are Alveolates

Answer 12

a group of single-celled organisms that include things like dinoflagellates, ciliates, and parasites such as Plasmodium (which causes malaria).
- They have tiny air-filled sacs under their membrane

Question 13

Why are alveolates important to the ecosystem

Answer 13

• Dinoflagellates are primary producers that generate energy through photosynthesis, supporting marine life.
• ciliates, help control bacterial populations

Question 14

What are apicomplexans (ex, Plasmodiums)

Answer 14

Alveolates that parasitize animals and spread through the host through tiny cells called sporozoites
- Most are both sexual and asexual in their life, often require 2+ host species for completion

Question 15

Ciliates have a ______ containing multiple copies of their genomes, and a _________ which may be diploid or haploid depending on their life stage

Answer 15

Macronuclei, Micronuclei

Question 16

What are Rhizarians

Answer 16

a group of mostly single-celled organisms that often have intricate, shell-like structures.
- They use thin, thread-like extensions (called pseudopodia) to move and capture food.

Question 17

What are Radiolarians

Answer 17

Delicate, symmetrical internal skeletons made of silica:
- use a reinforced pseudopodia to engulf microorganisms through phagocytosis

Question 18

What are Forams

Answer 18

Organisms with porous, multi-chambered calcium carbonate shells called tests

Question 19

The largest Archaeplastida are ____ _____, and they are ________ cellular

Answer 19

Red Algae, Multi

Question 20

_____ _____ are named from their green chloroplasts, two main groups of them are _______ which live in fresh saltwater, and ________ which include algae most closely related to plants

Answer 20

Green Algae, Chlorophytes, Charophytes

Question 21

What characteristics do the Unikonta group have

Answer 21

organisms that include amoebas, fungi, and animals.
- characterized by having a single flagellum (in some members) or being amoeboid, moving and feeding with extensions called pseudopodia

Question 22

Protists play two key roles in their habitats, ________ and ________

Answer 22

Symbionts, Photosynthesizers

Question 23

List some symbiotic roles of protists in their environment

Answer 23

• Dinoflagellates live within polyps and nourish corals
• Protists inhabit guts of termites and aid in wood digestion
• Plasmodium cause malaria in humans (parasitic role)
• Phytophthora ramorum cause oak death (parasitic)

Question 24

How does protists being photosynthesizers help their environment

Answer 24

Photosynthersizers produce organic compounds from light energy and CO2
- all other organisms (consumers) rely on producers for food.