Study Guides (380,000)
CA (150,000)
UOttawa (10,000)
BIO (1,000)
BIO 2135 (100)
Midterm

BIO 2135 Study Guide - Midterm Guide: Plastid, Cytoplasmic Streaming, Endoplasmic Reticulum


Department
Biology
Course Code
BIO 2135
Professor
Jon Houseman
Study Guide
Midterm

This preview shows pages 1-3. to view the full 11 pages of the document.
Protozoans Keywords
9+2 organization:
Structure found in core of eukaryotic flagellum (axoneme)
Consists of:
o 9 fused pains of microtubule doublets on outside
o Central microtubule
o The base of the flagellum, basal body
o Inner and outer dyenein arms that are responsible for the flagellar beating and
connect doublets
Actin:
A protein that forms microfilaments
Found in eukaryotic cells
One of the major components in microfilaments and the cytoskeleton
Functions:
o Cell mobility (with myosin motors)
o Cell division and cytokinesis (with myosin motors)
o Vesicle and organelle movement i.e. skeleton
o Muscle contraction
How amoebozoa change their shape, along with myosin motors
Myosin motors travel along actin fibres
Amoebozoa:
This group contains amoebas and other protozoans that move by using their mobile
extensions of the cytoplasm called pseudopodia (usually finger-like, large, and blunt
looking).
Nutrition in most forms is attained by phagocytosis.
Endoplasm is converted to ectoplasm at the front of the amoeba.
Amoebae move by the flowing of their cytoplasm over the surface of the mud or soil.
At one point of the amoeba the ectoplasms starts to spread out into a protuberance called a
pseudopodium and the fluid endoplasm follows.
In time, all the endoplasm will have flowed into the extending pseudopodium so that the amoeba is
brought to a new position.
Apicomplexa:
Malaria!

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

The mosquito is the definitive host.
The human is the intermediate host.
These are a large group of parasitic protists, most of which possess a unique organelle, a
type of plastid called an apicoplast, and an apical complex structure involved in
penetrating a host's cell.
Malaria Life Cycle:
1. A female mosquito carrying malaria parasites feeds on a human and injects the parasites
in the form of sporozoites into the bloodstream. The sporozoites travel to the liver and
invade liver cells.
2. The sporozoites grow, divide, and produce tens of thousands of haploid forms, called
merozoites, per liver cell. Some malaria parasite species remain dormant for extended
periods in the liver, causing relapses weeks or months later.
3. The merozoites exit the liver cells and re-enter the bloodstream, beginning a cycle of
invasion of red blood cells, asexual replication, and release of newly formed merozoites
from the red blood cells repeatedly. This multiplication can result in thousands of parasite-
infected cells in the human host bloodstream.
4. Some of the merozoite-infected blood cells leave the cycle of asexual multiplication.
Instead of replicating, the merozoites in these cells develop into sexual forms of the
parasite, called male and female gametocytes, that circulate in the bloodstream.
5. When a mosquito bites an infected human, it ingests the gametocytes. In the mosquito
gut, the infected human blood cells burst, releasing the gametocytes, which develop
further into mature sex cells called gametes. Male and female gametes fuse to form
diploid zygotes, which develop into actively moving ookinetes that burrow into the
mosquito midgut wall and form oocysts (stage of the malaria parasite within the mosquito
which is produced when male and female gametes combine).
6. Growth and division of each oocyst produces thousands of active haploid forms called
sporozoites. The oocyst then bursts, releasing sporozoites into the body cavity of the
mosquito, from which they travel to and invade the mosquito salivary glands. The cycle of
human infection re-starts when the mosquito takes a blood meal, injecting the sporozoites
from its salivary glands into the human bloodstream .
Other terminology related to malaria:
Trophozoite: is the activated, intracellular feeding stage in the apicomplexan life cycle.
After gorging itself on its host, the trophozoite undergoes schizogony and develops into a
schizont, later releasing merozoites. Therefore they eat animal cells, i.e. red blood cells.
Small % that become gametocytes for the mosquito to consume and complete the life
cycle.

Only pages 1-3 are available for preview. Some parts have been intentionally blurred.

Archaeplastida:
Red algae, green algae and land plants
Molecular evidence shows that Archaeplastida evolved from an endosymbiotic
relationship between a heterotrophic protist and a cyanobacterium.
Asexual reproduction:
Asexual reproduction is the primary form of reproduction for single-celled organisms such as
the archaebacteria, eubacteria, and protists. Many plants and fungi reproduce asexually as
well.
It is a mode of reproduction by which offspring arise from a single parent, and inherit the
genes of that parent only.
The offspring will be exact genetic copies of the parent.
Binary fission: division that creates 2 individuals
Multiple fission: division that create 1, 4, 8, 16 individuals
Alveolate:
major superphylum of protists
The most notable shared characteristic is the presence of cortical alveoli, flattened vesicles
packed into a continuous layer supporting the membrane, typically forming a flexible
pellicle.
Alveolates have mitochondria with tubular cristae and their flagella or cilia have a distinct
structure.
You're Reading a Preview

Unlock to view full version