BAHAS SOAL UTBK BIOLOGI • Materi Yang Sering Keluar di UTBK

Summary

In this educational video, the host provides a comprehensive review of biology concepts, focusing on key topics such as jellyfish classification, the structure of arthropods, and plant transportation methods. The video delves into the phylum Coelenterata, characteristics of jellyfish, and the four major classes of arthropods (crustaceans, arachnids, insects, and myriapods). Additionally, the host explains apoplast and symplast transport systems in plants, distinguishing between living and dead cell transport. The session is designed to help viewers prepare for UT BK exams with a mix of detailed explanations and interactive discussions.

Takeaways

• 😀 Jellyfish (Aurelia) belongs to the Coelenterata (Cnidaria) phylum, characterized by radial symmetry, diploblastic tissue structure, and the presence of stinging cells called nematocysts.
• 😀 The jellyfish's nervous system consists of nerve fibers and lacks a central nervous system (no brain or spinal cord).
• 😀 Arthropods are classified into four main groups: Crustaceans, Arachnids, Insects, and Myriapods, based on key characteristics like body segments and number of legs.
• 😀 Crustaceans (e.g., crabs) have 5 pairs of legs and a cephalothorax + abdomen body structure.
• 😀 Arachnids (e.g., spiders) have 4 pairs of legs and a cephalothorax + abdomen body structure.
• 😀 Insects have 3 pairs of legs, with separate body segments (head, thorax, abdomen), and are classified as hexapods.
• 😀 Myriapods include millipedes (with 2 pairs of legs per segment) and centipedes (with 1 pair per segment).
• 😀 The respiratory system in arthropods varies: Crustaceans use gills, arachnids use book lungs, while insects and myriapods use trachea.
• 😀 Apoplast and symplast refer to two types of water transport in plants, with apoplast moving water through cell walls and intercellular spaces (dead parts) and symplast through the living parts (cytoplasm and plasmodesmata).
• 😀 Apoplast transport is blocked by the Casparian strip in the endodermis, whereas symplast transport allows water movement through living cells in the root.
• 😀 Preparation for the UT BK exam involves understanding the classification of animals, transport mechanisms in plants, and differentiating between living and non-living transport pathways.

Q & A

What is the main characteristic of animals in the Coelenterata phylum?

Animals in the Coelenterata phylum, like jellyfish, have radial symmetry, are diploblastic, possess a single opening for both mouth and anus, and contain stinging cells (cnidocytes) that release venom.

What type of nervous system does a jellyfish have?

Jellyfish have a simple nervous system with nerve fibers or neurons, but they do not possess a central nervous system, brain, or spinal cord.

What are the key differences between the four classes of arthropods?

The four classes of arthropods (Crustacea, Arachnida, Insecta, and Myriapoda) differ in their body segments, number of legs, and other features. Crustaceans and arachnids have a cephalothorax and abdomen, insects have separate head, thorax, and abdomen, while myriapods have only a head and abdomen.

How can the number of legs help in identifying the class of an arthropod?

The number of legs varies by class: Crustaceans have five pairs (10 legs), arachnids have four pairs (8 legs), insects have three pairs (6 legs), and myriapods (like millipedes) have two pairs of legs per segment.

What is the role of the Casparian strip in plant transport?

The Casparian strip in plant roots blocks the apoplast transport pathway by preventing water from passing through the cell walls. It forces water to move through the symplast, ensuring selective absorption.

What is the difference between apoplast and symplast transport in plants?

Apoplast transport occurs through the dead parts of the cell, like cell walls or intercellular spaces, while symplast transport occurs through the living parts of the cell, including the cytoplasm and plasmodesmata.

Which part of a plant root does water pass through in apoplast transport?

In apoplast transport, water passes through the root hair, epidermis, cortex, and intercellular spaces before entering the xylem.

What are the characteristics of the Arachnida class of arthropods?

Arachnids, such as spiders and scorpions, have four pairs of legs, a cephalothorax (head and thorax fused), and an abdomen. They are distinct from other arthropods like insects, which have three pairs of legs.

What is the significance of plasmodesmata in plant cells?

Plasmodesmata are microscopic channels that connect plant cells, allowing for communication and the transport of substances, such as water, through the symplast pathway.

What are the different ways water can enter a plant through the root system?

Water can enter a plant through the root system via two pathways: the apoplast (through the spaces between cells or the cell walls) and the symplast (through living cell connections, specifically plasmodesmata).